455 Update

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

poncho462 - 15 Jan 2005 23:35 GMT

I got some time off today so I went to the shop with a buddy who works there
and we worked on the 72 455. We measured the deck height and checked the
balance on the rotating assembly. It doesn't sound like much, but it ate up
a lot of the day and we were interrupted a few times.

The new pistons are sweet and only weigh 465 grams. The Eagle rods are
pretty heavy but the bob weight is less than 2300 grams. For comparison, an
aluminum headed, roller cam 454 that went out a few days ago weighed in
around 2500 grams. The crank was cut 0.50 on the rods (IIRC) for the BBC
rods so the rotating assembly is a lot lighter than the stock setup; this
engine should rap up pretty quick. In addition, the crank is going to lose a
lot of meat to make up for all these changes so it gets lighter still. ;^)

The heads aren't done but the combustion chambers are looking pretty good.

Here's a link to a couple of pictures:

http://home1.gte.net/res03ax9/stuff/index.htm

Dave

Reply to this Message

BarracudaDesigns - 15 Jan 2005 23:59 GMT

> I got some time off today so I went to the shop with a buddy who works there
> and we worked on the 72 455. We measured the deck height and checked the
[quoted text clipped - 16 lines]
>
> Dave

Nice work, what pistons are you using? Look excellent to me.

Reply to this Message

poncho462 - 16 Jan 2005 02:41 GMT

> > I got some time off today so I went to the shop with a buddy who works
> there
[quoted text clipped - 22 lines]
>
> Nice work, what pistons are you using? Look excellent to me.

They are custom manufactured by BRC Performance in Florida. Basically a
Pontiac .030 over piston with a BBC pin diameter. The pin height is based on
the stroke and rod length. BBC rods are not only stronger but they are
cheaper that Pontiac rods. These pistons have a thicker crown since they
will see a lot of nitrous use. The valve reliefs are good to .700 lift at a
zero deck. I only know one shop that currently sells the custom line of
Pontiac pistons.

Dave

Reply to this Message

Thund3rstruck_n0i - 16 Jan 2005 04:26 GMT

poncho462 spilled my beer when they jumped on the table and proclaimed in
<hNhGd.5563$IP6.4097@trnddc05>

> I got some time off today so I went to the shop with a buddy who works
> there and we worked on the 72 455. We measured the deck height and checked
[quoted text clipped - 17 lines]
>
> Dave

Looks good man! Let us know how it turns out.

NOI

Reply to this Message

David Toft - 16 Jan 2005 10:18 GMT

>The heads aren't done but the combustion chambers are looking pretty good.
>
[quoted text clipped - 3 lines]
>
>Dave

I think I must be missing something here. I looked at the picture of the
combustion chamber, which looks a good shape and nicely polished, but
the valve seats overlap each other. If the valves are the same size as
the seats they will trip over each other. The only way round this that I
can see is that the exhaust valve is as big as its seat so that there is
a good sealing width and the inlet valve is very little bigger than the
port bore giving line contact on a radiused seat. But the seat doesn't
look radiused or three angle. What have I got wrong?

Regards,

Signature

David Toft

Reply to this Message

RSCamaro - 16 Jan 2005 11:42 GMT

>I think I must be missing something here. I looked at the picture of the
>combustion chamber, which looks a good shape and nicely polished, but
[quoted text clipped - 6 lines]
>
>Regards,

It's just an optical illusion. What you are looking at is replacement
intake and exhaust valve seats. Click on the picture to see it larger
and you can see where the intake valve seat has been cut into so the
exhaust seat could be replaced.

...Ron
--
68' Camaro RS
88' Firebird Formula
00' Mustang GT Vert

Reply to this Message