How to get 650 horse from my 396?

[CamaroJesse]

i have a 396 chevy big block. what would i need to do to get 600-650 crank horsepower out of it? natually aspirated. i know id need heads and a cam but how big? it already has 11-11.5 to 1 compression. also itd have to be suitable for road racing. not alot of road racing tho. mostly lots of street beating.

thanks Jesse

[MonzaRacer]

Well first give AFR a call on heads. Those will definately help in power production.
BUT first and formost road racing with that from a shorter stroke big block isnt going to be as productive as building a flat torque curve and hook it up.
I personally love my 402 and I am going to up date the heads/pistons soon and get back in shape but it turned out 391 lb ft of torque at the rear wheels which was flat out astounding, then dyno operator brought out his SS 396 Chevelle with a well built AFR headed 396 and stumped me by pulling out a rip snorting 476 lb ft of torque and showed me the engine dyno numbers and industry calculated losses through the drive line for each of our cars and my was estimated at the 489lb ft at fly wheel. This was my goal to build a 500 lb ft of torque from a 396/402.
Now if you really want to make torque and keep the 396 block swap in a 454 crank and stroke it for a monster small inch torque engine.
If you intend to do some high rpm work you may want to think about storing the stocker and look at a 496 or 502 crate engine as they will have warranties from GM.
They say nothing beats cubic inches but if the wallet cant find the cubic dollars we poor fellas have to make do.
My preference would be ,if that is original block for car is store it and find a good 454 block and built a sweet 427, extra cubs, and you dont really need super huge high dollar heads to flow the air.
See its a ballance of parts that get you results. too nuch torque and you spend cubic dollars on the suspension to hold it to the ground but give up a lot of versatility.
I would forget the 6 numbered hp figures and build your set up to run a sweet ,flat moderately low torque number ,say keep it in the 3000 to 5000 and let the engine breath well enough to support the top end charge. nad use a little squeeze or positive preasure to expand the power production.
My 402 is going to get a set of smaller AFRs set to make good flow down low and not choke down at higher RPMS, I will use a Cam Motion custom hydralic grind and a retrofit liffters to paly the game, I will use Megasquirt FI management with my Flex FI set up, and I will use the Victor Jr I have with bungs and a couple of 670 TPI throttle bodies from LT1s/TPIs added, Then tune the exhaust for a sweet sound and not too large to kill torque too much. Maybe hook it to a TKO600 and then scrounge up another 70 Monte like I used to have and set it up to burn a corner.
Some say that small engines are defunct but Ill spend 10k and go fast rather than 25 k and go broke.
With the 11 to 11.5 compression your gonna need either aluminum heads or maybe see if E85 available locally for you (as it 105 octane).
10 to 10.5 with aluminum heads would be better choice as you need to be able to keep it civil for the street.
Good luck
Lee Abel

[Bandit]

BB 396 + https://static1.pt-content.com/images/noimg.gif = 650hp

[triplecap]

Sorry I'm a little late on this thread, but I saw this and it reminded my of my old 396' BBC I had shoe-horned in a 66' Nova. My setup was done on a budget, 2 bolt mains, stock crank, forged pistons, ported cast heads, 11.2:1 comp. and a .630" solid cam. This was good for about 575 HP and it ran on 92 (although it liked the 100 much better). It was a really pipey motor, below 4500 rpm it was tame, but from 4500-8000 it was a monster. To make the power you want to make, I'd invest a little more on the bottom end (steel crank, i-beam rods (h-beams are too heavy), forged pistons... and with a set of nice aluminum heads and a hefty solid roller you'll be able to make 650 hp. Forget about torque though... these motors don't make big hp and big torque numbers at the same time. Since you're running a manual you'll be able to keep the motor in it's power band fairly easily.

Eric

[Ricoch3T]

Now if you really want to make torque and keep the 396 block swap in a 454 crank and stroke it for a monster small inch torque engine.
If you intend to do some high rpm work you may want to think about storing the stocker and look at a 496 or 502 crate engine as they will have warranties from GM.

Lee Abel

We just did this on one of my dads friends motor out of his chevelle. I think we ended up with 427 cubic inches when we were done. Its a nice sounding motor. Although I didnt' get to ride in the car so I could compare the two, I hear it made decent power!