Hot Rod Forum : Hotrodders Bulletin Board

Hot Rod Forum : Hotrodders Bulletin Board (
-   Hotrodding Basics (
-   -   2 sbc questions (

jo5hi3 12-14-2003 06:47 PM

2 sbc questions
will a 2 bolt main be able to handle a 425 hp 383 stroker? also would a pair of double hump heads work well with the stroker?

killerformula 12-14-2003 06:48 PM

Yes and no.

Your two bolt is good to 500 horse

The hump heads only have 1.94 valves and will most likely not make 425 horse under any circumstance.


jo5hi3 12-14-2003 06:58 PM

ok one more question what size valves and chambers do i need to get that 425? 12-14-2003 07:19 PM

you will need at least a 2.02 or 2.08 intake with 1.60 exhaust in aftermkt heads to get these hp. figures

DoubleVision 12-14-2003 07:25 PM

Likely a set of dart Iron Eagle heads with 72cc chambers and 180cc runners with 2.02 1.60 valves. the humps would have to be ported pretty good, along with the valves installed, they`ll likely need valve guides and the studs replaced with springs, locks, retainers, the works and your looking at about $800 unless you can port them yourself and get the proper results and this isn`t counting what you paid for them to start with, it just makes better sense and cheaper prices just to go with a aftermarket head. if you find a set of ready to go double humps then you could have them bowl ported but you still likely won`t reach 425 horses, more likely 385. also comes down to what pistons your running since the double humps have 64cc chambers and with flat top pistons in a 383 will put you over 10:1 compression which won`t survive on pump gas if this is street intended.

killerformula 12-14-2003 08:12 PM

Oh you can push much higher than 10:1 on pump gas if you do it right. I know a couple of guys pushing 12. Lluciano77 uses 11.5 on 91 octane because he lives in cali!!!

Its all about that dynamic comp ratio


DoubleVision 12-14-2003 08:33 PM

I`m well aware of that killer, but I`m not going to take the time to explain it all on how to run that kind of compression on pump gas to a 16 year old and hope he understands it.

jo5hi3 12-14-2003 08:41 PM

look just because i am 16 does not mean anything i know alot more about cars then just normal people do so dont put me down like that just cause i ask questions about heads does not mean anything. all i want is an anwser to my question and actually i prolly would understand the thing about the gas

DoubleVision 12-14-2003 08:43 PM

it`s not a put down to say I wasn`t going to explain it to you when there`s lots of books and articles out there that can teach you and tell you a whole lot better than I ever could in just a posting.

Robinson Robin 12-14-2003 09:31 PM

Ya its usually better to air on the side of caution with compression ratio's especially if you havent had a whole lot of experience. Most the guys that manage to run high static comp ratio's on the street have though out the combo very carfully and often had to do some trial and error. There isn't a whole lot of power to be gained from for example going from running high compression ratio's either although it does help restore some of the power at low rpms when running a cam with alot of duration

rifraf 12-14-2003 10:03 PM

Yea,10 and above your pushin it and ya better know whats up after that,383 motors build great torque but don't spin well unless your wallet is fat. I would run 10 or less with a cold thermostat ,curve the distributor,cold plugs,and either settle for 375 with big torque or build something else , unless your loaded. Still not enough info.Sorry.

killerformula 12-14-2003 10:13 PM

I think I'd have to disagree. Sure stroker motors aren't the best rappers, but if you ballance a motor (which you must do with a stroker) you can push 55-6000. I also am positive you can make well into the 400 horse range with a stroker, you just need decent heads and a good cam. You can even use a stock botom end up to 500 HP no problem. Stick with a duel plane intake and you're cool. You don't need a fat pocket book. That's the reason 383's are so popular, they make great power and they're cheap.


rifraf 12-14-2003 10:34 PM

500 horse on a stock bottom end ,yea,sure for how long,one run. Better take the money you saved and buy a good scatter shield to protect you from the turned down cast crank .400 ,yea ,Ill bite but come on.

killerformula 12-14-2003 10:43 PM

?? No, I think you're too skeptical about stock parts. Hers's proof of my claim, scroll down to the section about rods-



Robinson Robin 12-14-2003 11:12 PM

The small blocks chevs and very strong bottom ends even in 2 bolt main form, a cast crank and a set of reconditioned rods with high quality rod bolts could easily survive making 425. That seems to be a mistake alot of people make. they spend way to much money on after market high priced pieces when its the necisiarry and sometimes won't even life as long as stock pieces will.Don't ever under estimate stock parts

All times are GMT -6. The time now is 03:51 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999 - 2012. All Rights Reserved.