Aftermarket blocks in SSers
 

Well, until now we have run stock Pontiac blocks. After about 10 years of pursuit NHRA finally allowed us to use the aftermarket block a couple of years ago. I just ordered mine. We have extensive dyno work with the 455SD and the stock blocks.

I remember a huge discussion(mostly denial) about how aftermarket blocks make power. Yes if you do everything the same, it probably makes the same power. Yes, I still have to run the cast iron heads. I cant cut the deck much due to the 4.210 stroke and 6.625 rod.

Anyone want to make a guess on how much power this is worth? We are going to find out for sure.

Re: Aftermarket blocks in SSers
 

25-35 HP for a Pontiac, all else being equal in preparation.

Re: Aftermarket blocks in SSers
 

That's probably a good number, Jeff. Im always a little on the conservitive side when it comes to HP numbers. From a stock Pontiac block to the aftermarket blocks (Im guessing it's either the IA from Butler or the MR-1 Kauffman), you should gane a ton of stability in the cylinders. Let alone the solid valley...!

Re: Aftermarket blocks in SSers
 

What if any is the difference in weight?

Re: Aftermarket blocks in SSers
 

Dont know exactly, but I have been told like 70lbs heavier. Since there is more meat in the sleeves then we dont have to fill the blocks or install the braces on the lifter bores. I fill the entire area with epoxy after installing the brace to keep the block from moving around. I will see how much more net weight. Pontiac 455s benefit with weight on the front anyways to keep the wheels down.