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Car Forum / BMW Cars / April 2004Hemi??
What's with the big mystique with Chrysler and the hemi? I thought quite a few major manufacturers, including BMW, tried and abandoned the hemi as a less than ideal solution for combustion chamber design. It falls short in terms of squish, swirl, scavenge and is, geometrically speaking an expensive and complicated design to implement. It's only real advantage is in uniform flame propagation. Surely, there must be more efficient designs out there. What is BMW using now? what exactly is the "hemi"? Imad > What's with the big mystique with Chrysler and the hemi? I thought quite >a few major manufacturers, including BMW, tried and abandoned the hemi as a [quoted text clipped - 5 lines] > > Another advantage is a favorable area-to-volume ratio, something that limits the rotary BTW. > What's with the big mystique with Chrysler and the hemi? I thought quite > a few major manufacturers, including BMW, tried and abandoned the hemi as a [quoted text clipped - 3 lines] > flame propagation. Surely, there must be more efficient designs out there. > What is BMW using now? Actually, BMW and virtually all OHC engines are *essentially* hemi engines. The OHC allows positioning the valves for "flow-through" breathing. If you look at BMW's pics of their head (there's one on p24/25 of my '01 3-series brochure) you will see this. The hemi design is more complicated, as it is a pushrod V8 that has a rocker design that allow positioning the valves on different sides of the head in the same manner that the OHC design gives you more naturally. The current hemi engine uses two spark plugs rather than one to improve the flame front and combustion. However, the pushrod design makes casting and building the heads less expensive - rocker arms are lighter and need less lubrication than a camshaft. Floyd > What's with the big mystique with Chrysler and the hemi? I > thought quite a few major manufacturers, including BMW, tried and [quoted text clipped - 4 lines] > Surely, there must be more efficient designs out there. What is BMW > using now? Chrysler was building hemis before BMW was building real cars, and before anyone understood much about combustion chamber gas flow. In the 1950 and into the 60s, Chrysler was at the forefront of internal combustion engine design. Matt O. Actually, the very first use of hemispherical heads was in the 1920s. The advantages of the hemis are well known as is the significantly increased cost of production. As I recall, Chrysler abandoned the hemi heads to save money. Jim > > What's with the big mystique with Chrysler and the hemi? I > > thought quite a few major manufacturers, including BMW, tried and [quoted text clipped - 10 lines] > > Matt O. What made the original Hemi different was that it had overhead valves, one on each side of the engine as opposed to side-valves which were still common at the time. Today Hemi has little meaning, any engine with 3 or more valves pr. cylinder is essentially a hemi engine. 2-valve DOHC engines are too. For me the most interesting thing about the current Hemi engines is the pushrod design, abandoned decades ago on pretty much every other continent. The principles of a hemi engine were by no means invented by Chrysler. The 1914 Alfa Romeo Grand Prix had all the features of the Hemi (overhaed valve, crossflow design etc.). No pushrods, though, DOHC. > > What's with the big mystique with Chrysler and the hemi? I > > thought quite a few major manufacturers, including BMW, tried and [quoted text clipped - 10 lines] > > Matt O. >What made the original Hemi different was that it had overhead valves, >one on each side of the engine as opposed to side-valves which were [quoted text clipped - 3 lines] >Hemi engines is the pushrod design, abandoned decades ago on pretty much >every other continent. I'll bet there are many times as many "penthouse roof" head designs in the current market lineups than true hemis... > Hemi engines is the pushrod design, abandoned decades ago on pretty much > every other continent. Pushrods can do the same thing as camshaft engines except they are lighter and smaller. The only downside is that to get the same power, you have to make a larger displacement engine, but even still the engine is smaller and lighter than a comprable camshaft engine. Richard > > Hemi engines is the pushrod design, abandoned decades ago on pretty much > > every other continent. [quoted text clipped - 3 lines] > make a larger displacement engine, but even still the engine is smaller and > lighter than a comprable camshaft engine. ...and the pushrod engine's rpms will be *severely* limited in comparison due to having such a cumbersome valve-train. Pushrod engine design is antiquated. The ONLY value to the whole Chrysler corporation "hemi" marketing campaign is to dupe the less knowledgeable consumers into thinking it has something more than historical significance. <kid in clapped out car> "Hey man, has that thing got a hemi?" <middle aged man in Dodge truck with Dodge ball cap nods> "Yeah!" <kid in car> "Aw, that's too bad... Now if had VTEC or VANOS or maybe a Turbo Diesel of anything close to the same displacement it might be able to get out of it's own way..." -Fred W > ...and the pushrod engine's rpms will be *severely* limited in comparison > due to having such a cumbersome valve-train. Now waaaaaaitaminute. There are all sorts of small-block Chevies out there turning at 8500-9000rpm; stop by your nearest dragstrip. > Pushrod engine design is antiquated. It's different. Pretty much any mechanical way you can think of to operate the valves has been around ninety years or more. They're *all* antiquated. ><kid in car> "Aw, that's too bad... Now if had VTEC or VANOS or maybe a > Turbo Diesel of anything close to the same displacement it might be able to > get out of it's own way..." You may find this month's Car & Driver of interest. The new Chrysler 300c Hemi turns a 5.3 second 0-60, a 13.something-second quarter-mile, and returns fuel economy in the 25mpg range. Compared to my 330i, it's much bigger, much faster, ten thousand dollars cheaper, and just as economical. It makes 340hp and 390 lb-ft of torque from 5.7 litres. The BMW V8 makes 325hp and 330 lb-ft of torque, and while it is of smaller displacement it appears to chug more gas in a very similar application (the 745Li). I would also bet that the actual engine weights are similar for the BMW and Chrysler motors. So. Compared to a premium quad-cam V8, the antiquated pushrod Hemi pulls ahead in power, torque, economy, and cost. Not too bad, eh? > You may find this month's Car & Driver of interest. The new Chrysler > 300c Hemi turns a 5.3 second 0-60, a 13.something-second quarter-mile, [quoted text clipped - 8 lines] > So. Compared to a premium quad-cam V8, the antiquated pushrod Hemi > pulls ahead in power, torque, economy, and cost. Not too bad, eh? Road & Track, May, 2004: Tested Price 0-60 Skidpad Slalom Gas Mileage Chrysler 300C: $37,310 5.6 .79g 62.4 18.1 *BMW 330i: $39,519 6.1 .86g 65.4 25.9 **BMW 745i: $76,766 6.3 .87g 64.9 17.7 Gas mileage was R&T observed, not EPA. *330i tested 7/02, *745i tested 6/02. So the Chrysler costs only $2,000 less than your 330i, has significantly higher fuel consumption, and weighs about 800 pounds more. And when the road gets curvy, either BMW easily outdistances the Chrysler. Tom > Chrysler 300C: $37,310 5.6 .79g 62.4 18.1 > *BMW 330i: $39,519 6.1 .86g 65.4 25.9 > **BMW 745i: $76,766 6.3 .87g 64.9 17.7 Never mind all that comparison stuff, I want to meet the fellow who can get twenty-six miles out of a non-Imperial gallon in a 330i! :) > Never mind all that comparison stuff, I want to meet the fellow who > can get twenty-six miles out of a non-Imperial gallon in a 330i! :) I'm not sure of the conversion figure, but at cruise I'd expect a 330 to do well into the '30s UK. Of course *overall* consumption depends on so many things as to be near useless as a guide. Autocar in the UK have a standard test route they take all cars over - it's a mixture of urban and suburban fast(ish) roads. That at least allows comparison between makes and models. Giving an overall figure for a test isn't a fair comparison as traffic conditions and the way it's driven will vary enormously.  Signature*I want it all and I want it delivered Dave Plowman dave.sound@argonet.co.uk London SW 12 RIP Acorn "Jack Baruth" <jack@caarco.com> wrote > > Chrysler 300C: $37,310 5.6 .79g 62.4 18.1 > > *BMW 330i: $39,519 6.1 .86g 65.4 25.9 > > **BMW 745i: $76,766 6.3 .87g 64.9 17.7 > > Never mind all that comparison stuff, I want to meet the fellow who > can get twenty-six miles out of a non-Imperial gallon in a 330i! :) I routinely get about 28 mpg highway (~ 70mph) in my 330xi. Mostly I get around 24.5 mixed, and have gotten as high as 30. And with the lower numerical rear end and lower stance that 2WD 330's have I would expect it to be about 1mpg better. FloydR > > You may find this month's Car & Driver of interest. The new Chrysler > > 300c Hemi turns a 5.3 second 0-60, a 13.something-second quarter-mile, [quoted text clipped - 23 lines] > > Tom ....and most of the performance and economy gains on the hemi are due to advances in engine management systems, not combustion chamber design. > Road & Track, May, 2004: > Tested Price 0-60 Skidpad Slalom Gas Mileage [quoted text clipped - 8 lines] > higher fuel consumption, and weighs about 800 pounds more. And when the > road gets curvy, either BMW easily outdistances the Chrysler. My suspicion is if you get the right tires on the 300c it's skidpad and slalom will imporve dramatically. Not to BMW levels, but the car it should really be measured against is the 545, and at 20 to 25 grand difference many people would choose the 300C. Those slalom results are when the cars are at the very edge, and most people don't drive that way, and never see that need in their total time of ownership. Personally I think the 0-60 time is of more use in everday American driving than slalom times are anyway. I love my BMW's, but realize not everyone wants to drive like i do, so why spend the money?. Every report I've read so far says that at normal driving speeds, whether highway or street, the 300C comports itself spectacularly. To qualify that statement though, I must admit I think most auto magazine writers are pinheads. An American company has developed a car that by all accounts is fantastic, has taken it's own road and doesn't aspire to being a BMW clone (like every other "Sports Sedan" out there), and is getting it to the market at reasonably low prices. I applaud the effort and hope the sucker sells like hotcakes. > You may find this month's Car & Driver of interest. The new Chrysler > 300c Hemi turns a 5.3 second 0-60, a 13.something-second quarter-mile, [quoted text clipped - 4 lines] > smaller displacement it appears to chug more gas in a very similar > application (the 745Li). The 745Li is a huge car with a vast kerb weight. No point in trying to compare the relative fuel economy of US and European cars, now is there :). > I would also bet that the actual engine weights > are similar for the BMW and Chrysler motors. Er, OK... it's your money! "Andrew Thomas" <andrewj_nospamthomas@yahoo.com.au> wrote > Jack Baruth <jack@calrco.com> wrote > > I would also bet that the actual engine weights > > are similar for the BMW and Chrysler motors. > > Er, OK... it's your money! Jack would lose: the BMW has an aluminum block, the Hemi an iron block (aluminum heads only). Floyd > "Andrew Thomas" <andrewj_nospamthomas@yahoo.com.au> wrote >> Jack Baruth <jack@calrco.com> wrote [quoted text clipped - 5 lines] > Jack would lose: the BMW has an aluminum block, the Hemi > an iron block (aluminum heads only). Ah, but the question becomes: Is the Hemi compact enough to pick up that material difference back? From what I have read it is a very compact engine. >>> Jack Baruth <jack@calrco.com> wrote >>>> I would also bet that the actual engine weights [quoted text clipped - 8 lines] > to pick up that material difference back? From what I have > read it is a very compact engine. This is true -- an aluminum block engine isn't necessarily lighter overall. BTW, the heaviest part of most modern engines is actually the crank. Matt O. >>> Jack would lose: the BMW has an aluminum block, the Hemi >>> an iron block (aluminum heads only). [quoted text clipped - 5 lines] > This is true -- an aluminum block engine isn't necessarily lighter overall. > BTW, the heaviest part of most modern engines is actually the crank. When I had my XJ6 many years ago, I remember looking into the cost of the Chevrolet swaps (oh, stuff it, all of you). What struck me as amusing was that, according to John's Cars, the original iron-block six and ally V12 weighed about the same. Both of them weighed more than a 350ci small-block Chevy, and the V12 cars were actually set up very well to take a 454ci Chevy big-block with no cutting, welding, or... changing of front springs. If you were going to use a small-block, you had to buy new springs for the lighter motor; for the big-block, the existing springs were fine! > When I had my XJ6 many years ago, I remember looking into the > cost of the Chevrolet swaps (oh, stuff it, all of you). What [quoted text clipped - 6 lines] > new springs for the lighter motor; for the big-block, the existing > springs were fine! Well, based on that, I know which one I'd choose... and it would probably still get better gas mileage than either Jag engine! Matt O. "Jack Baruth" <jack@calamco.com> wrote > Ah, but the question becomes: Is the Hemi compact enough > to pick up that material difference back? From what I have > read it is a very compact engine. It is compact because it is *not* OHC, not because the block is small. Probably the block is bigger than that of the 4.4L BMW V8, as the biggest that engine can go is 5.0L (in the M5). Floyd > You may find this month's Car & Driver of interest. The new Chrysler > 300c Hemi turns a 5.3 second 0-60, a 13.something-second quarter-mile, > and returns fuel economy in the 25mpg range. That's highway miles. Overall the Chrysler is good for about 18 combined. >Compared to my 330i, it's > much bigger, much faster, ten thousand dollars cheaper, and just as > economical. Really! My 330i routinely did around 30mpg on the highway and low 20's in the city. How does that make the Chrysler as economical? >It makes 340hp and 390 lb-ft of torque from 5.7 litres. > The BMW V8 makes 325hp and 330 lb-ft of torque, and while it is of > smaller displacement it appears to chug more gas in a very similar > application (the 745Li). I would also bet that the actual engine weights > are similar for the BMW and Chrysler motors. The 745i weighs in at another 400 pounds+ heavier. The 300C is closer in weight to a 545i-In this case, power, economy, etc. are fairly even. The 545 is a more evenly balanced car front to rear, leading me to believe that the BMW engine is probably lighter. Given the displacement difference, I also find it hard to believe the iron block Chrysler engine would be more compact. > So. Compared to a premium quad-cam V8, the antiquated pushrod Hemi > pulls ahead in power, torque, economy, and cost. Not too bad, eh? Take a quad-cam 8 and pump it up to 5.7 liters. Add in that little V-8-6-4 revival trick that Chrysler uses and see what happens. My guess is even more power and even better economy. I'm kind of wary of that part of the new hemi. But they probably needed it to keep the car from being a guzzler. Cadillac built a real dog of an engine with that system. Hopefully Chrysler got it right. Only time will tell. Overall, though, the best Mopar in a long time, with kudos to Benz for the help. > Take a quad-cam 8 and pump it up to 5.7 liters. Add in that little > V-8-6-4 revival trick that Chrysler uses and see what happens. I'm curious about this 'switching off' of cylinders at certain times. It seems such a simple idea to implement on a modern engine with modern electronic control that I wonder just what the down side is? Signature*Sometimes I wake up grumpy; Other times I let him sleep. Dave Plowman dave.sound@argonet.co.uk London SW 12 RIP Acorn >> Take a quad-cam 8 and pump it up to 5.7 liters. Add in that little >> V-8-6-4 revival trick that Chrysler uses and see what happens. > >I'm curious about this 'switching off' of cylinders at certain times. It >seems such a simple idea to implement on a modern engine with modern >electronic control that I wonder just what the down side is? Cadillac tried it (in the 80's irc) and it wasn't received well enough to continue. It was the 8-6-4 system - and as I remember it, it was the 6-cylinder mode that produced the most engine vibration and commensurate complaints. I believe Chrysler's system is 8-4 only - which would avoid the unpleasant 6. >> Take a quad-cam 8 and pump it up to 5.7 liters. Add in that little >> V-8-6-4 revival trick that Chrysler uses and see what happens. > > I'm curious about this 'switching off' of cylinders at certain times. It > seems such a simple idea to implement on a modern engine with modern > electronic control that I wonder just what the down side is? It seems Chrysler has done a pretty good engineering job on it, as it seems to work well without being noticeable. Of course, the valves have to be held open, and I'd imagine that this part of the system could be susceptible to problems in the long term. From what I gather, this is one area where Cadillac ran into trouble. >>>Take a quad-cam 8 and pump it up to 5.7 liters. Add in that little >>>V-8-6-4 revival trick that Chrysler uses and see what happens. [quoted text clipped - 8 lines] > problems in the long term. From what I gather, this is one area where > Cadillac ran into trouble. I thought the valves were held *closed* in the original Caddy 8-6-4 design. that would make the most sense from an engineering standpoint as that would eliminate pumping losses from the deactivated cylinders. I do recall that in the later Northstar engine in a "limp mode" 4 cylinders would be deactivated at a time with air pumped through normally - to cool them off under conditions of severe overheating. But that's something entirely different, and far less efficient. nate Signaturego dry to reply. http://www.toad.net/~njnagel > >>>Take a quad-cam 8 and pump it up to 5.7 liters. Add in that little > >>>V-8-6-4 revival trick that Chrysler uses and see what happens. [quoted text clipped - 18 lines] > > nate Wouldn't you incur greater losses by continually compressing air in the deactivated cylinders? I thought the biggest problem with the deactivated cylinders was keeping them hot to match the active cylinders. Also, didn't BMW experiment with pumping exhaust gases from the active cylinders to the idle cylinders to keep them hot? Personally, I'd just alternate the cylinders to keep them all active but half the time and no, I haven't really thought it through to see if would work that way. Maybe I could get a job at Chrysler. > > >>>Take a quad-cam 8 and pump it up to 5.7 liters. Add in that little > > >>>V-8-6-4 revival trick that Chrysler uses and see what happens. [quoted text clipped - 24 lines] > Wouldn't you incur greater losses by continually compressing air in the > deactivated cylinders? Nah, because you will get it all back on the downstroke. you're just continually compressing and expanding the same volume of gas over and over again, so the only losses would be ring and bearing friction. > I thought the biggest problem with the deactivated cylinders was keeping > them hot to match the active cylinders. Also, didn't BMW experiment with > pumping exhaust gases from the active cylinders to the idle cylinders to > keep them hot? Personally, I'd just alternate the cylinders to keep them all > active but half the time and no, I haven't really thought it through to see > if would work that way. Maybe I could get a job at Chrysler. no comment :) nate [snipped] > I thought the biggest problem with the deactivated cylinders was keeping >them hot to match the active cylinders. Also, didn't BMW experiment with >pumping exhaust gases from the active cylinders to the idle cylinders to >keep them hot? Personally, I'd just alternate the cylinders to keep them all >active but half the time and no, I haven't really thought it through to see >if would work that way. That's a brilliant idea, really. >Maybe I could get a job at Chrysler. I could imagine worse things ;-) > [snipped] > > I thought the biggest problem with the deactivated cylinders was keeping [quoted text clipped - 5 lines] > > That's a brilliant idea, really. Well gee, thanks. Oh great, now I can't get my hat on :) > >Maybe I could get a job at Chrysler. > > I could imagine worse things ;-) Well I can't. > Really! My 330i routinely did around 30mpg on the highway and low 20's in > the city. How does that make the Chrysler as economical? I'd like to take a ride with you some time and see how you do it. In normal enthusiastic driving, not counting autocrossing and track time, my 330i gets about 23mpg to the US gallon, mixed freeway and city. > Given the displacement difference, I also > find it hard to believe the iron block Chrysler engine would be more > compact. As another poster pointed out, a pushrod engine can be fairly compact for its displacement, because the heads are small. >> So. Compared to a premium quad-cam V8, the antiquated pushrod Hemi >> pulls ahead in power, torque, economy, and cost. Not too bad, eh? > > Take a quad-cam 8 and pump it up to 5.7 liters. Add in that little V-8-6-4 > revival trick that Chrysler uses and see what happens. My guess is even more > power and even better economy. Well, at this point we're cheating. If an engine takes in less fuel and produces more power, as seems to be the case with the Hemi v. the Bimmer 4.4, then does it really matter what the displacement is, assuming you live in a country which does not tax displacement? The five-liter BMW eight makes more power than the Hemi (although not as much torque) but it is well-known for being thirsty. > Cadillac built a real dog of an engine with that system. Hopefully Chrysler > got it right. Only time will tell. Overall, though, the best Mopar in a > long time, with kudos to Benz for the help. Here I would disagree. To my mind, the best Mopar in a long time is the new Dodge Neon Mopar Stage 2 turbo. 2800lbs, 265 horsepower to the front wheels... with a cat-back Mopar exhaust they are turning 12.8 second quarter-miles, and a 235hp version finished sixth place in One Lap or America. Mine's on order :) > Here I would disagree. To my mind, the best Mopar in a long time is > the new Dodge Neon Mopar Stage 2 turbo. 2800lbs, 265 horsepower to the > front wheels... with a cat-back Mopar exhaust they are turning 12.8 > second quarter-miles, and a 235hp version finished sixth place in One > Lap or America. Mine's on order :) C'mon, Jack, you can't really think a lowbrow American econobox, built in THE MIDWEST fer chrissake, could possibly approach the power, refinement, and quality of a fine European automobile, built by men in white lab coats with Wagner playing in the background! Matt O. >> Here I would disagree. To my mind, the best Mopar in a long time is >> the new Dodge Neon Mopar Stage 2 turbo. 2800lbs, 265 horsepower to the [quoted text clipped - 6 lines] > quality of a fine European automobile, built by men in white lab coats with > Wagner playing in the background! I know you're dripping with sarcasm here, but do you really believe the Neon has the refinement and quality level of a BMW or Mercedes? I don't doubt the track performance potential, but this is not the kind of car I'd ever want as a daily driver. In article <BCB53D5F.1B3E1%jmsent2@comcast.net>, John Stone wrote: > in article iLPjc.99251$L31.56028@nwrddc01.gnilink.net, Matt O'Toole at > matt@deltanet.com wrote on 4/28/04 10:05 AM: >>> Here I would disagree. To my mind, the best Mopar in a long time is >>> the new Dodge Neon Mopar Stage 2 turbo. 2800lbs, 265 horsepower to the [quoted text clipped - 11 lines] > the track performance potential, but this is not the kind of car I'd ever > want as a daily driver. Refinement, heck no. Driving the 330i and the Neon back to back, it's patently obvious what you get for your extra $17,000 (or thereabouts - the Bimmer cost $42K and the Neon is $22K plus $3K of coilovers and added boost). The 330i is quiet, it rides better, and the interior is plainly nicer. But. The Belvedere (Il.) Bomber strikes back as soon as you decide to make rapid progress. Unlike, say, an E46 M3 where the first six thousand revs are relatively sedate, the Neon (excuse me, they are calling it the SRT-4) spools up to 1 bar of boost right away and starts pulling out in a torque-steer-free fashion. The seat is better-bolstered than the BMW Sport seats. The steering isn't any worse than my 2001 E46. The brakes are about the same - smaller rotors on the Neon stopping about 500lbs less weight. Plus, the car is just plain larger inside. At 6'2" I can't really "sit behind myself" in an E46; in the lighter Neon I can do it with ease. What sealed the deal for me in my choice (which was boiled down to this car, a 330i ZHP, and a few others) was Mopar's commitment to the trackday people. Want rebound-adjustable coilovers? Thirteen hundred bucks. There are three factory-provided levels of turbo upgrades, with the first two being emissions-legal (and Stage 2 even has a 100 octane setting button so you can show EVOs and STis your taillights, to say nothing of an M3). And they are racing the car in SCCA T2 this year and sharing the development info with the userbase. And while the interior won't exactly make Audi quake with fear, it's no worse than a C-Class and appears slightly better screwed-down. So, to reiterate: Ugly little sedan, faster than the sports cars costing twice as much, strong racing support, fanatical userbase. As a BMWCCA member, I think I've seen this formula before :) > As another poster pointed out, a pushrod engine can be fairly compact > for its displacement, because the heads are small. That would make it less tall - but wider. Not that the width would change with a V-8 which has plenty of wasted space. Signature*Reality? Is that where the pizza delivery guy comes from? Dave Plowman dave.sound@argonet.co.uk London SW 12 RIP Acorn > Chrysler was building hemis before BMW was building real cars, and > before anyone understood much about combustion chamber gas flow. Err, the classic Jaguar XK engine - in production from '47 - was a twin OHC design with hemi heads. > In the 1950 and into the 60s, Chrysler was at the forefront of internal > combustion engine design. Do us a favour. ;-) Building cheap powerful engines based on size and efficiency not being important, maybe. Signature*If you think nobody cares about you, try missing a couple of payments * Dave Plowman dave.sound@argonet.co.uk London SW 12 RIP Acorn > Do us a favour. ;-) Building cheap powerful engines based on size and > efficiency not being important, maybe. I suspect that the old Hemi (not the old, *old* Hemi) was as weight- and fuel-efficient as any other five-hundred-horsepower stock motor of the Sixties, assuming there *were* any other such. > I suspect that the old Hemi (not the old, *old* Hemi) was as weight- > and fuel-efficient as any other five-hundred-horsepower stock motor of > the Sixties, assuming there *were* any other such. Think you'll find the '500 horsepower' 'stock motor' of the '60s produced nowhere near this. Try nearer 300. Signature*Never miss a good chance to shut up * Dave Plowman dave.sound@argonet.co.uk London SW 12 RIP Acorn >> I suspect that the old Hemi (not the old, *old* Hemi) was as weight- >> and fuel-efficient as any other five-hundred-horsepower stock motor of >> the Sixties, assuming there *were* any other such. > > Think you'll find the '500 horsepower' 'stock motor' of the '60s produced > nowhere near this. Try nearer 300. Or twice that: www.budgetperformance.com/articles/hemidart/ While the infamous Hemi Dart was probably the exception that proved the rule about street Hemis, I don't think that all those mid-twelve-second factory RoadRunners out there were only turning three hundred horsies, even at the rear wheels. Y'know, the three-valve Benz V8 is a bit of an underachiever in normally-aspirated trim. Wonder if there would be any percentage in calling the Kokomo plant and creating a run of American-market-only, 350-hp E570 (or, given past history, E430 5.7) models? Previous-gen E55 performance for the price of an E320. Better living through pushrods, don't you know! Disclaimer: My only personal pushrod experience in quite some time comes in the form of my Disco 4.6, which does, in fact, perfectly demonstrate every sin attributed to a single-cam motor, being short of breath, slow to rev, and possessed of a Rosie O'Donnell-esque thirst for fuel.... but if you hold the gas and brake to 2500rpm, it'll chirp 'em all off the line! :) > My only personal pushrod experience in quite some time > comes in the form of my Disco 4.6, which does, in fact, perfectly > demonstrate every sin attributed to a single-cam motor, being short of > breath, slow to rev, and possessed of a Rosie O'Donnell-esque thirst > for fuel.... but if you hold the gas and brake to 2500rpm, it'll chirp > 'em all off the line! :) Just in case you think I'm criticizing push rod engines - I've got a Rover SD1 fitted with the 3.5 version of that V-8 with the first generation EFI system from Lucas - although it's mainly Bosch parts. And it's not short of breath in that guise - it will see off my E39, although has a lower rev limit. The 4.6 unit is designed for torque in the Disco, but other versions produce much more power. Signature*I'm not as think as you drunk I am. Dave Plowman dave.sound@argonet.co.uk London SW 12 RIP Acorn > Just in case you think I'm criticizing push rod engines - I've got a Rover > SD1 fitted with the 3.5 version of that V-8 with the first generation EFI > system from Lucas - although it's mainly Bosch parts. And it's not short > of breath in that guise - it will see off my E39, although has a lower rev > limit. The 4.6 unit is designed for torque in the Disco, but other > versions produce much more power. Not the 4 liter unit used in US versions of Disco for many years. I don't think that unit ever got 50 horses per liter in US trim. I think that standard was 188? Which is just about what Jeep's aged archaic (I guess that applies to both engines in question :^) 4.0 I6 provided, though more torque than the Land Rover's 4.0. I must say though, that the Disco's 4.0 did indeed aspire to the reliability of Jeep's bulletproof 4.0, and came pretty close. Jeep will dump that engine one day soon in exchange for one of the derivative architecture V's Jeep is currently using. Oh, well...I still got one in my TJ :^) >> Just in case you think I'm criticizing push rod engines - I've got a Rover >> SD1 fitted with the 3.5 version of that V-8 with the first generation EFI [quoted text clipped - 5 lines] > Not the 4 liter unit used in US versions of Disco for many years. I don't > think that unit ever got 50 horses per liter in US trim. The SD1, IIRC, used the 3.5L Rover V8. That appears to have been the UK version of the small-block Chevy, appearing in everything from the Range Rover to the P5 Rover automobile to the Westfield SEight, with a few stops in TVRs (with the five-litre Griffith being perhaps the meanest of the range), the Triumph TR8, and the US-market Defender 90. > I think that > standard was 188? Which is just about what Jeep's aged archaic (I guess that > applies to both engines in question :^) 4.0 I6 provided, though more torque > than the Land Rover's 4.0. Yup, although having had a five-speed 4.0 Disco the motor just felt lighter on its toes than the Jeep six does. > I must say though, that the Disco's 4.0 did indeed aspire to the reliability > of Jeep's bulletproof 4.0, and came pretty close. Jeep will dump that engine > one day soon in exchange for one of the derivative architecture V's Jeep is > currently using. Oh, well...I still got one in my TJ :^) Contrary to public perception there are a fair number of 150,000 mile Discos crunching around the US. All the electrics are shot but they can still climb a rock! Talk about the tragedy of the disappearing inline six... I sold Fords in the twilight years of the old 4.9L straight six. If ever there was a "truck motor" this was it. It had 130hp but felt like it had twice that. Compared to a 302 V8 it was just plain better and more characterful. The 4.2L V6 which replaced it had better numbers but was uninspiring to drive. > The SD1, IIRC, used the 3.5L Rover V8. That appears to have been the > UK version of the small-block Chevy, appearing in everything from the > Range Rover to the P5 Rover automobile to the Westfield SEight, with a > few stops in TVRs (with the five-litre Griffith being perhaps the > meanest of the range), the Triumph TR8, and the US-market Defender 90. The original Rover installations were in the P5 and P6 which became the P5B and P6B - B for Buick. I think its lowest state of tune was in carburettor Land Rover guise - under 130 bhp. Signature*Learn from your parents' mistakes - use birth control Dave Plowman dave.sound@argonet.co.uk London SW 12 RIP Acorn > > I think that > > standard was 188? Which is just about what Jeep's aged archaic (I guess that [quoted text clipped - 3 lines] > Yup, although having had a five-speed 4.0 Disco the motor just felt > lighter on its toes than the Jeep six does. Spoken like a true Disco owner! The reality (for anyone other than a disco owner :^) is that the I6 is a better engine. In some cases I think the reason Jeep and Disco powerplants are often misunderstood is that some people (not meaning you) don't understand that for offroad vehicles the true products have throttle response and tip-in characteristics that lend themselves to the particular offroad formula or design built in to each models weight, drivetrain, gear ratios and 4x4 system. Jeeps tend have a longer throttle than Land Rovers, particularly the 4.0 and 2.5 engines, and better low end grunt (torque charts for both 4.0 engines issued by both companies seem to validate this). In the end I think they are both worthwhile offroad engines, and certainly off road vehicles. I think the Jeep 4.0 is the better road engine, but it probably comes down to personal preference and maybe even familiarity. The LR 4.0, at least to me, seemed to work better in the D90 than Disco and I'm not certain why that is. I think the Disco and D90 had the same gear and granny ratios (maybe I'm wrong on this point). > > I must say though, that the Disco's 4.0 did indeed aspire to the reliability > > of Jeep's bulletproof 4.0, and came pretty close. Jeep will dump that engine [quoted text clipped - 4 lines] > Discos crunching around the US. All the electrics are shot but they > can still climb a rock! That engine is well known for being a reliable son-of-a-gun. I'm wondering of LR has completely ceased using it, or there is still application for it in some other markets. More so than a lot of other companies (well, maybe other than Toyota's Land Cruiser lineup) LR seems to have a very disparate set of trim levels for varying parts of the world. > Talk about the tragedy of the disappearing inline six... I sold Fords > in the twilight years of the old 4.9L straight six. If ever there was > a "truck motor" this was it. It had 130hp but felt like it had twice > that. Compared to a 302 V8 it was just plain better and more > characterful. The 4.2L V6 which replaced it had better numbers but was > uninspiring to drive. I have had the opportunity to drive the GM I6, not a lot but some, and find that an impressive unit as well. Maybe a bit dressed up in that it spins a bit higher than a truck owner might want, especially for 4.2 liters, but it seems a quality unit. Don't know what it's reliability record is though...that will take a few more years to discern. > That engine is well known for being a reliable son-of-a-gun. I'm > wondering of LR has completely ceased using it, or there is still > application for it in some other markets. IIRC, the engine production line was up for sale recently. Ford, who own Land Rover, have no need for such an engine. I reckon with modern mass production techniques it wasn't that cheap to make. Signature*He who dies with the most toys is, nonetheless, dead. Dave Plowman dave.sound@argonet.co.uk London SW 12 RIP Acorn > IIRC, the engine production line was up for sale recently. Ford, who own > Land Rover, have no need for such an engine. I reckon with modern mass > production techniques it wasn't that cheap to make. I believe I read some time ago that BMW will not continue supplying engines for the RR so with the selling off of LR's engine capacity what does it look like for Land Rover petrol vehicles? Ford powerplants maybe tweaked by Jag? What are they planning for the D90 (current or future model)? Did LR make it's own diesels? >> IIRC, the engine production line was up for sale recently. Ford, who own >> Land Rover, have no need for such an engine. I reckon with modern mass >> production techniques it wasn't that cheap to make. > > I believe I read some time ago that BMW will not continue supplying engines > for the RR It's my understanding that they are contracted to do so as long as that model is in production. However, they are *not* contracted to provide the upgrades et al so this year the X5 has the new ~325hp motor while the Rangie continues with the E38-spec 282hp one. > so with the selling off of LR's engine capacity what does it look > like for Land Rover petrol vehicles? Ford powerplants maybe tweaked by Jag? The new Disco and Range Rover Sport (called "My First Range Rover" in the alt.fan.landrover group) will use the Jag V8 retuned for more torque and less output. The current Freelander uses the Rover KV6 provided by the Phoenix folks aka MG Rover. > What are they planning for the D90 (current or future model)? Did LR make > it's own diesels? I believe that the Td5, which is Rover-built, accounts for pretty much all D90 sales nowadays. The V8-powered Defenders were mostly US-market. Some Rangies and many Discos are Td5 as well, outside the States. The next big engine question is certainly what the Freelander successor will use. Will it continue with Rover K-series four-and-six-cylinder petrol power in addition to the Rover Td4, or will it pick up a Jag- spec Duratec six and four? > I believe that the Td5, which is Rover-built, accounts for pretty much > all D90 sales nowadays. The V8-powered Defenders were mostly US-market. > Some Rangies and many Discos are Td5 as well, outside the States. Isn't the BMW 6 cylinder diesel still available for the Rangie? Signature*He who dies with the most toys is, nonetheless, dead. Dave Plowman dave.sound@argonet.co.uk London SW 12 RIP Acorn > I believe that the Td5, which is Rover-built, accounts for pretty much > all D90 sales nowadays. A couple years ago I did a Great White Shark/Safari trip in Gansbaai and Grootbos, respectively, and our hired D90 was fitted with a BMW 2.8 I6 petrol engine. Never saw that anywhere else in the world. > A couple years ago I did a Great White Shark/Safari trip in Gansbaai and > Grootbos, respectively, and our hired D90 was fitted with a BMW 2.8 I6 > petrol engine. Never saw that anywhere else in the world. Years ago, they made a petrol 6 cylinder using a version of the old Rover overhead inlet, side exhaust valve engine. Even less economical than the V-8. ;-) Signature*When a clock is hungry it goes back four seconds.* Dave Plowman dave.sound@argonet.co.uk London SW 12 RIP Acorn > Y'know, the three-valve Benz V8 is a bit of an underachiever > in normally-aspirated trim. Very true, which is why AMG has had to use forced induction to match or pass M's ambient breathing engines. Mercedes has decided that their future AMG motors will not be forced and are building larger liter engines with the ability to rev for horses. Advertising to those too young to remember the 1950s. > What's with the big mystique with Chrysler and the hemi? Hemispherical heads and piston allowed for increased combustion/power I believe the earlier chrys/RT models conrods were slightly longer allowing the piston head to reach a higher point in the cycle. note traditional engine the piston high point in the stroke comes up flush with the top of the block. This is my understanding of the meaning of the HEMI Drove a column 265 RT / HEMI with triple SD in the late eighties it pulled as hard as most GM 8cyl's of the period. Quite an efficent deliverer of top end power > Advertising to those too young to remember the 1950s. > > What's with the big mystique with Chrysler and the hemi? > Hemispherical heads and piston allowed for increased combustion/power I > believe the earlier chrys/RT models conrods were slightly longer allowing [quoted text clipped - 10 lines] > > Advertising to those too young to remember the 1950s. > > > What's with the big mystique with Chrysler and the hemi? Na, pistons cannot travel above the deck height of the block. Hemis typically use a crowned piston to solve the "squish" problem. >Hemispherical heads and piston allowed for increased combustion/power I >believe the earlier chrys/RT models conrods were slightly longer allowing [quoted text clipped - 3 lines] > >This is my understanding of the meaning of the HEMI WRONG___________--------------- HEMI is short for HEMISPHERICAL or 1/2 a tennis ball shape with an inlet valve on one side and an exhaust valve on the other. The inrush of cool fresh petrol laden air would cool the exhaust valves and the exiting exhaust gas sucked in the fresh mixture. efficiency was HIGH as was POWER but economy (with gas at 10c a gallon) was non existent. The reason the engine was technically dropped from production was because of COST but were kept available (you can buy a real 1968-1972 426 Hemi straight from the parts dept of the local Mopar dealer for racing purposes only $$$$$$$$$$$$$$) The 383 CID Wedge was brought in and then the 440 Wedge with triple Holly 2Bbl carbs called the SP or six pack (I once had a Charger with the 440 SP and although 0-60 was in the 5 sec bracket and the 1/4 mile was around 13 sec the gas mileage was about 4 MPG and it didn't like going round corners at any speed over 30 MPH. So HEMI is short for HEMISPHERICAL Hugh >Drove a column 265 RT / HEMI with triple SD in the late eighties it pulled >as hard as most GM 8cyl's of the period. Quite an efficent deliverer of top >end power > >> Advertising to those too young to remember the 1950s. >> > What's with the big mystique with Chrysler and the hemi? Intelligence is not knowing the answer but knowing where and how to find it! Hugh Gundersen hsg@h-gee.co.uk hsg@bognor-bill.co.uk http://www.bognor-bill.co.uk Bognor Regis, W.Sussex, England, UK ------------------------------------------------- Vyisder Asmeni Orsisarsis Asderisorsis. B.Cozderiz Vunarz PERORZ ------------------------------------------------- >Hemispherical heads and piston allowed for increased combustion/power I >believe the earlier chrys/RT models conrods were slightly longer allowing [quoted text clipped - 3 lines] > >This is my understanding of the meaning of the HEMI WRONG___________--------------- HEMI is short for HEMISPHERICAL or 1/2 a tennis ball shape with an inlet valve on one side and an exhaust valve on the other. The inrush of cool fresh petrol laden air would cool the exhaust valves and the exiting exhaust gas sucked in the fresh mixture. efficiency was HIGH as was POWER but economy (with gas at 10c a gallon) was non existent. The reason the engine was technically dropped from production was because of COST but were kept available (you can buy a real 1968-1972 426 Hemi straight from the parts dept of the local Mopar dealer for racing purposes only $$$$$$$$$$$$$$) The 383 CID Wedge was brought in and then the 440 Wedge with triple Holly 2Bbl carbs called the SP or six pack (I once had a Charger with the 440 SP and although 0-60 was in the 5 sec bracket and the 1/4 mile was around 13 sec the gas mileage was about 4 MPG and it didn't like going round corners at any speed over 30 MPH. So HEMI is short for HEMISPHERICAL Hugh >Drove a column 265 RT / HEMI with triple SD in the late eighties it pulled >as hard as most GM 8cyl's of the period. Quite an efficent deliverer of top >end power > >> Advertising to those too young to remember the 1950s. >> > What's with the big mystique with Chrysler and the hemi? Intelligence is not knowing the answer but knowing where and how to find it! Hugh Gundersen hsg@h-gee.co.uk hsg@bognor-bill.co.uk http://www.bognor-bill.co.uk Bognor Regis, W.Sussex, England, UK ------------------------------------------------- Vyisder Asmeni Orsisarsis Asderisorsis. B.Cozderiz Vunarz PERORZ ------------------------------------------------- > (with gas at 10c a gallon) Where was that? In the '50's & '60's, U.S. gas was 25 to 30 cents except for the occasional "gas war" dips to about 20 cents in certain areas. Tom >> (with gas at 10c a gallon) > >Where was that? In the '50's & '60's, U.S. gas was 25 to 30 cents except >for the occasional "gas war" dips to about 20 cents in certain areas. > >Tom At that time I had no idea what gas prices were in the US my Charger was in the UK imported from California and reputedly used in a couple of movies - Bulitt was mentioned but cannot prove it. Nice car but......... @ 6 MPG UK gallons it was EXPENSIVE still I made a cool 8K GBpounds profit when I sold it. Hugh Intelligence is not knowing the answer but knowing where and how to find it! Hugh Gundersen hsg@h-gee.co.uk hsg@bognor-bill.co.uk http://www.bognor-bill.co.uk Bognor Regis, W.Sussex, England, UK ------------------------------------------------- Vyisder Asmeni Orsisarsis Asderisorsis. B.Cozderiz Vunarz PERORZ ------------------------------------------------- > At that time I had no idea what gas prices were in the US my Charger was in the UK > imported from California and reputedly used in a couple of movies - > Bulitt was mentioned but cannot prove it. That's easy. How many hubcaps did it have? SignatureIgnasi. '90 325is (using SPAM trap e-mail address) > >Hemispherical heads and piston allowed for increased combustion/power I > >believe the earlier chrys/RT models conrods were slightly longer allowing [quoted text clipped - 18 lines] > > So HEMI is short for HEMISPHERICAL You're getting all semantic on us. For most people Hemi means the Chrysler "pushrod" unit with hemispherical heads. That's why 4 valve engines by other manufacturers, which have hemispherical heads, are not called "Hemi". It's pretty much understood the term applies to the Chrysler pushrod units. So really, "Hemi" is short for much more than "hemispherical". Date: Sat, 13 May 2000 From: "Gary Derian" <gderian@oh.verio.com> Subject: Re: [uuc] Combustion Chamber Shape Most 2 valve engines are wedge but BMW's are all hemispherical, but not like the Chrysler hemi. The BMW 2 valve heads are more like a polysphere, the centerlines of the valves are skew instead of in the same plane. This design gives better swirl and combustion speed than the Chrysler hemi. Air cooled Porsche engines have Chrysler like hemi chambers. They solved the combustion chamber shape problem with dual spark plugs, as did Chrysler in the race engines. All 4 valve engines are hemi, BMW, Chevy, Ford, etc. Gary Derian gderian@oh.verio.com Also.. look at this.. http://autozine.kyul.net/classic/bmw.htm > What's with the big mystique with Chrysler and the hemi? I thought quite > a few major manufacturers, including BMW, tried and abandoned the hemi as a [quoted text clipped - 3 lines] > flame propagation. Surely, there must be more efficient designs out there. > What is BMW using now? |
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