[NHRASuperStock455SD]

Goquick,

We are talking race cars right? There has always been an argument about blocks with notches or leaving them out for the additional compression. I favor the opinion that notches to improve flow does better than the additional compression. Pontiac engineers did this for a good reason. If you take a bare block, bolt your heads to it and look up the cylinder wall at the intake valve it will scare you to death. It did me.

We all go 60 overbore anyway, and we usually offset bore the blocks to relieve intake valve shrouding. Of course you have to start with a standard bore block the get the most and check the cylinder wall thickness.

Many of us do 8 sleeves like the motor sitting on my engine stand. You must also hard block them all.

Lynn

[goquick]

The reason I asked is that I have a couple yh code 428's and wondering if in the right car it could be made competitive with the larger valve heads.

[johnta1]

I don't believe the codes matter, just the bore, stroke and main bearing size for the appropiate engine.

Example: 428 would need 4.12" bore, 4" stroke and 3.25" main block.

[goquick]

So my next question would be what if the 428 was put in a new body, such as the cobalt? (well, they let chevies get put iin Pontiacs!)

[NHRASuperStock455SD]

Originally Posted by goquick

So my next question would be what if the 428 was put in a new body, such as the cobalt? (well, they let chevies get put iin Pontiacs!)

We are doing a big D-port engine for the new Grand Am. It will run GTAA with an index of 10.40. We are confident it will make upwards of 700HP. Been waiting over 2 years on the heads.

Not sure if a Cobalt would work. Of course you would pick the Pontiac version wouldnt you? The big problem is carb spacer on the new cars which is a must on our Pontiacs.

The GrandAm had a Ram Air hood, so that is why we went with that. Of course it also was given to us by Pontiac Racing.

The least expensive way to get a light SS GT car is to buy my Sunbird and keep about $80k in your pocket.

Lynn

[goquick]

LYNN,
The cobalt idea is a "stick it in your chevy loving face" thing I love to do. Kind of my way of payback to all the idiots who put a chevy in their Pontiacs over the years. Of course, if I could get away with it, a 69 rs/ss camaro or a 67 chevelle that originally a ss 396 4 gear would be fun with a Pontiac engine too. Of course I did about 17 years ago fix a 68 ss 396 chevelle with a Pontiac 400 from a wadded up 69 GTO. over rated 396 best e.t. was high 13's, and with the Pontiac 400 I ran 13.02. Not bad for a stock engine and headers. The 396 had exactly same type set up, stock, & headers.

[Wareagle]

Originally Posted by goquick

LYNN,
The cobalt idea is a "stick it in your chevy loving face" thing I love to do. Kind of my way of payback to all the idiots who put a chevy in their Pontiacs over the years. Of course, if I could get away with it, a 69 rs/ss camaro or a 67 chevelle that originally a ss 396 4 gear would be fun with a Pontiac engine too. Of course I did about 17 years ago fix a 68 ss 396 chevelle with a Pontiac 400 from a wadded up 69 GTO. over rated 396 best e.t. was high 13's, and with the Pontiac 400 I ran 13.02. Not bad for a stock engine and headers. The 396 had exactly same type set up, stock, & headers.

Now that would be cool--some guy winning the SUPER STOCK Championship in a Pontiac powered Cobalt.

[NHRASuperStock455SD]

Originally Posted by goquick

The reason I asked is that I have a couple yh code 428's and wondering if in the right car it could be made competitive with the larger valve heads.

Agree with johnta1. NHRA has the bores listed at 4.125. They also just released the new ruling that you can go 75 over instead of 70.

Depending on your wall thickness, I would go 4.195 bore. The 428 engine is probably the best Pontiac ever made.

Lynn