385 stroker combo yay or nay

350 Bare block bored .040 over and stroker clearenced. (clearence is on the bottom of the cylinder walls)
casting number-40 GM 3970010....350...69-80...2 or 4.
68 - 79 350 & 327 145-375 2&4-Bolt mains/Truck/Hi Perf
Mine is 4 bolt mains. With the 010 indicating higher nickel content.


I am looking to make over 400hp and lots of torque, think this will get me there? if not what can i do? Anyone have a dyno sim?

Eagle cast steel 3.750 crank
Eagle SIR I-beam bushed connect rods (5.7)
Speedpro/keithblack hypers -5cc 10.7:1cr w/64cc heads
Dart iron eagle platinum 200cc/64cc 2.02/1.60
performer RPM airgap, 750 cfm carb and a comp 292h (Duration @ .050 244)(Valve lift 0.501)(Lobe lift 0.334)(RPM range 3000 to 6500)(Lobe center angle 110) with a 3000 stall and 4.10's out back. TH400 tranny.


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Looks like a good combo to me. You can always nitpick details, but overall it seems to be matched well. I'd say an honest 400 hp no problem. Bragging to friends many would call that 450 hp.
You might want to consider a victor jr intake.

thanks for the imput

Myself, I wouldn't use the hyper pistons, especially if it will really be a 10.7-1 compression. That is pushing it with Iron heads if you intend to run pump gas. Run it into detonation hard just once and you will learn what exploded hypers and broken block looks like. Lower the compression or go forged pistons if this is a pump gas engine. The rest of the combo looks ok.

Personally, I don't like hyper pistons. People tend to assume that they can get away with more with them because they beleive the marketing hype, when they are still a cast piston, they just have a higher silicon content. They shatter easily if things are not perfect in the combustion process.

yeah i jus figured the hypers would do ok for this mildish build. How about spending the extra 400 bucks on some alumminum afr's? Would that allow the hypers to be ok?

how about a slightly taller gasket to help lower compression alittle. Something i dont understand about compression.. does less compression nessessarily mean less power?

10.7 is at the upper limit, but still doable with iron heads. I have an engine with 10.5 and I run 94 octane with zero issues.
The important thing is to have ideal quench. If I remember correctly ideal quench is about .040-.050 (perhaps somebody who knows more about this than me will chime in). It is possible to induce detonation by using a gasket which is too thick and therefore causes too much quench space which can promote detonation. You might want to measure the deck height on the block. It may be that your compression will be slightly lower than calculated, and it is also worthwhile to verify that your quench is close to ideal.

anymore advice anyone?