[sonomadog]

ok, im building a 400 sbc. Looking for any advice for combinations to produce about 375 hp without spending an arm and a leg. I will more than likely bore it .30 over and go with 10 to 1 compression pistons. not sure what length of rods i need to go with, thought about 202 heads, with a dual 4 barrel intake, msd ignition, and a nice size cam. Im pretty much stuck from there. any advice will help, good or bad. Thanks.

 

[DoubleVision]

375 horse 400? easy. D-Dish pistons, Vortec heads,dual plane Vortec intake, .224 duration @.050 cam. 5.7 rods. HEI, Quadrajet carb, small tube headers, dual exhaust with X pipe and turbo mufflers. This is a basic off the shelf build and with a 400 it`ll easily make 375. But there`s likely a 1000 combo`s to reach that power level. You could go with a bigger and better cam like comp`s line or lunati`s voodoo series. I`m sure others will happily chime in on this thread and give you better details and different combo`s than I. The one I listed is a basic cheapy build. Just remember, whatever heads you use make sure you have the steam holes drilled.

 

[sonomadog]

400 sbc

would i be able to produce that kind of hp with factory heads?

 

[sonomadog]

400 sbc

and ill be running i believe 40 series flow masters, electric water pump, headers will be tricky though, this engine is going in a s-10

 

[techinspector1]

would i be able to produce that kind of hp with factory heads?

L31 Vortecs will put you there easily. Best production head ever produced by Chevrolet. They need some work if you're gonna use more than 0.450" valve lift, but you can get cams that limit the lift and still give you more duration. If you find some boneyard heads, get the valve covers and rail rockers with them. Disassemble them down to bare castings, clean them up and have them magnafluxed for cracks.

The stock valve springs are pretty cheezy, but will get you by on a low rpm street motor with a moderate cam and rail rockers. If you want more, cut the spring seats for larger diameter springs and cut the o.d. of the valve guide so you can fit dampers inside the springs without them rubbing on the o.d. of the guide (it's a fat guide). If you're going that far, you might as well cut the guides for PC seals too and shorten the guide for more lift without interference between the bottom of the retainer and the seal.
http://www.chevyhiperformance.com/techarticles/148_0208_vortec_heads_valve_lift/index.html

 

[SSedan64]

Chevrolet 406 - The Impersonator

The Impersonator SBC406, 525 lb-ft of peak torque at 3,500 and 428 peak horsepower at 5,000 rpm >> http://www.chevyhiperformance.com/techarticles/148_0306_chevrolet_406_big_block_torque/index.html

Chevrolet 406 CI Engine Build - Impersonator II
525 lb-ft and 490 hp From an 87-Octane 406
http://www.chevyhiperformance.com/techarticles/148_0401_chevrolet_406_ci_engine_build/index.html

 

[sonomadog]

im not sure what size cam i should go with because i want the torque and hp, but i want to be able to drive it on the street. not sure what size torque converter to use either.. any advice????

 

[sonomadog]

haven't taken the engine apart yet, i just picked it up for $300. the guy i bought it from said its guaranteed to run as is.......... but he didn't say how good it would run. I hope i can go the cheap way, but until i pull the motor down i wont know. budget is pretty tight, i have a baby on the way. It's a project so i will just buy a little at a time. im just trying to get plan together for the engine, im looking to start the actual build in march. if everything goes right.