2-bolt 396 Block hp handling..

slideways

slideways

Club Member
whats a stock bottom end 396 2-bolt good till, it has arp bolts, its in my dad chevelle been together for a few years, but hes looking at uping the compression and doin a new cam and wants to know what his limit will be
 
What's the rest of the motor? More than likely, that bottom end will more than handle what a little more compression/cam will add.
 
well hes looking to be makin 450ish at the crank maybe 500, its just a mild cruiser, holley carb, edelbrock performer rpm, stock crank,rods hyperutetic pistons stock oval ports with 3 angle valve job and some light porting as it sits, Hes looking to up the compression, maybe mess with theheads a little bit and put a custom grind cam in not lookign to spend alot of money he just wants to make sure he woudlent have to worry about rappin on it with 450-500hp he liek to drive it hard
 
He might be able to get out to 450 h.p. without bumping the compression.
What pistons and heads is he using now? With a good port job and the right cam, he could get there.
 
If you're trying to go it as cheap as possible, leave the bottom end alone. It'll handle 450-500, especially with some good ARP bolts. Assuming they are some decent oval port heads, 450 shouldn't be any problem.
 
The heads are stock oval ports of a 72 motor, 3 angle valve job, pretty much just gasket matched and cleaned up
 
slideways said:
whats a stock bottom end 396 2-bolt good till, it has arp bolts, its in my dad chevelle been together for a few years, but hes looking at uping the compression and doin a new cam and wants to know what his limit will be
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With Stock bolts and a factory balance The main cap bolts will hang out till around 6500rpm and the stock rods bolts with a 3.76 inch stroke will be good for around a reliable 6300ish. to make 500hp at the crankshaft given typical Tq output you'll need to turn 7000rpm. Not a big deal IMO with god rod bolts and Main studs and a good balance job as Foolsgold80z eluded to. Your engine should have a steel crank in it from the factory. Is it a thin dampner motor ?

I would use the Edelbrock RPM performer oval ports and a mild hydrualic roller camshaft. I even have a grind i can recomend that should get that big pig a rocking. Compression is something you will want to up to around 10.5:1 with aluminum heads. I have built similar combos on the cheap before. If you want give me a ring I have a few old build sheets laying around.
 
leave it to SEAN to pop in With the best information THANKS! he wants to stick to the stock heads its got oval ports, already got a performer RPM on it, hell be happy with 450crank hp compression is 9.0:1 right now, hes considering going 95:1 but if he can make 450 with out it with just a cam swap hed be happy, what kind of cam specs should we be looking for?


Again thanks a ton i always apperciate your post
 
slideways said:
leave it to SEAN to pop in With the best information THANKS! he wants to stick to the stock heads its got oval ports, already got a performer RPM on it, hell be happy with 450crank hp compression is 9.0:1 right now, hes considering going 95:1 but if he can make 450 with out it with just a cam swap hed be happy, what kind of cam specs should we be looking for?


Again thanks a ton i always apperciate your post
Click to expand...

Stock heads will require a much wilder camshaft then it would with a good set of edelbrock performer rpm oval ports to make the same HP. Last I checked these heads cost less then a good P&P on stock heads and would allow you to run more compression. If you are shooting for this much power i would really recomend pulling the motor studing the lower end and putting ARP 2000 series or better bolts in those rods. Really for your goals i think you should consider rebuiding the motor with updated parts as a JIC.This way it will be able to take the RPM and make the HP without worrying about scattering.

the P#60499 RPM 454-0 High Compression Heads milled about .030 would put you at 8.5:1 or better with a flat top. Use a thin gasket and a slightly domed piston and you could net an easy 10.5:1 which would certianly run alot better. Its a closed chamber which will be good for quench

Summit has these bad dads for about $1600 for the pair. I have seen them for less out there used on Ebay however.

things to consider ? whats the MAX bore the block can handle ? can you bore it to a 4.250 block ? If so you just got yourself a cheap 427 BBC and it will make more again with less camshaft.

396 = 4.096" x 3.76"
402 = 4.125" x 3.76"
427 = 4.250" x 3.76"


http://www.edelbrock.com/automotive_new/mc/heads/chevrolet_bb_performer.shtml

Those heads should work great on a small engine the nice part is that with a + 13cc dome ( Read Dome and Quench) that would net you 9.5:1 and thats with a 100cc chamber. If you want even more squeeze you will need more bore.

I like the Idea of building a 396 but why not dare to be a bit different ? a 0.60 overbore 4.165 bore with a 4 inch stroke a set of custom pistons 430+ cubes and you could have a nice little sneaky low deck screamer.
 
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