well got another.. no one gives the pontiac 350 any respect.. everyone wants the 400 ...  I am confused.. according to Hand's Max performance V8 pontiacs...

the bore on the stock 350 is 3.875  
the bore on the stock 400 is 4.12

both have the same stroke - 3.75...

the difference in the bore is only approx. .30 between the two??...

If this is correct.. where does the extra 50 cubes come from - heads? - 400 head open chamber ??

But then open chambers lowers the compression??

This is where it gets really confusing...

Sooo.. can I get 400 cubes about of a 350 with .30 over bore & 400 heads..? stroker crank ??

Suggestions for Pontiac max. HP & torque.. short block 350 rebuild.. - with a set of 70 400 GP heads (13)  

Thanks,  

wow.. feel like an idiot .. just read the swmall-bore
350 buildup on this site.. this site kicks ass.. any other input would be appreciated..  

Double check your math, you are reading the 400 bore as "four inches and twelve thousandths of an inch" when it should be four inches and one-hundred and twenty thousandths of an inch. Looking at it another way- you are reading 4.12 as 4.012" instead of 4.120" which is the correst way. A 400 bore .145" or one-hundred and forty-five thousandths of an inch bigger than a 350 bore. No you can't bore a 350 out to a 400, the cylinder walls aren't thick enough and while the stroke of the crank is the same the balance is different to accomodate the different weight pistons. If you check some of the other threads about 350's you will find lots of info on here, you may have to go back a few months and they are not all on the appropriate heading ie:drivetrain. If you can't find them, let me know and I'll try to direct you to them.  

PPR's 350/383 stroker is a very nice motor- hardcore racing parts and all. But how much hp would a 400/468 make it treated to the same buildup and parts? My guesstimate is maybe 75-100 hp more. It would be interesting to see a comparison 468 built up to similar specs and dynoed.

Geno  

I agree with Blackbird72, the 383 build-up is cool, but probably overkill as far as price vs power is concerned. The 350 can be a strong performer in mild street form, but if you are looking to go wild, a 400 or 455 based motor with the same parts will likely make considerably more power for less money (no exotic stroker stuff needed) with all the same top-end parts.
I'm surprised more guys don't upgrade their 350's to the 68-69 350HO specs, I understand Jeff Sawruk has his 69 Tempest Custom S in the high 12's with a supertuned stock combo 350HO. I might even try it myself if I find some older heads.  

I agree with Blackbird72, the 383 build-up is cool, but probably overkill as far as price vs power is concerned. The 350 can be a strong performer in mild street form, but if you are looking to go wild, a 400 or 455 based motor with the same parts will likely make considerably more power for less money (no exotic stroker stuff needed) with all the same top-end parts.
I'm surprised more guys don't upgrade their 350's to the 68-69 350HO specs, I understand Jeff Sawruk has his 69 Tempest Custom S in the high 12's with a supertuned stock combo 350HO. I might even try it myself if I find some older heads.