331 Stoker kit ?

lower compression with no change in boost equals less power. I don't know how much but you have to crank the boost up to get back to the same power you had with the stock compression. Ray, this is more of a question for the power adder forum....

Got the description from google"1.5 kenne bell 5.0" .........Allfords.com had it

poneypower89 said:

Nope, I seen it (the 1.5l kb) in his sig.... I figured he would just be re-using it. The only reason I brought my original post up was because I've seen a lot of guys sell their 1.5l after moving to a 347 stroker and realizing the blower was too little to be efficient.

EDIT: Also wanted to know... Where did you get that description from???

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Yep... this is correct. Let's not forget that we're talking about a POSITIVE DISPLACEMENT supercharger here. With twinscrews, boost level is a side effect of the back pressure of the air volume that it's trying to force into the motor. On a good functioning, good flowing, 331, that 1.5L blower is not going to be able to provide the air volume necesssary to give you the boost levels that you've got in mind. The 1.5L starts falling off at around 5500 to 6000 RPM pushing roughly 8 lbs through a stock 302. It wil not be able to provide that same boost to a larger motor and becomes very ineficient when you try spinning it faster. You're going to need a larger displacement supercharger to feed a stroker.

The description that Sureshot found explains it pretty well. When the motor becomes effecient enough, it's going to be trying to suck air through that blower while it waits for it to provide the air that it's looking for. Of course, that's not going to happen since the motor will still be spinning up ahead of the supercharger (this is over simplified but you should get my meaning).

If you intend to use the KB that you've already got, I'd suggest doing a 306 with forged rods and pistons and finding a cam and heads that will make the most out that blower.

For one, the 1.5 is too small of a blower for an animal of a stroker with it on there, the blowzilla or flowzilla is what one really needs.

As for compression, it is all a matter of blueprinting and choosing carefully. Basically, the lower the compression, the lower the power output without boost. BUT, since the compression ratio is lower, more boost is able to be had. the tradeoff is yes you lose a few ponies when you lower compression, but boost has a larger impact on power output than compression - so it definitely can overcome it.

The magic question that is and has always been to power adder junkies is "how much boost can I run on pump gas?" It is just that, more compression + more boost = more likely for detonation. You can only run but so much compression with so much boost before the detonation demon haunts.

As for the KB kits, the old 5.0's do not have an integrated cooler, but methanol/water injection kits have had a lot of success with the KB mainly due to the fact that the injection takes place before the unit and then passes through it whereas a centrifugal does not have that luxury. These kits, like the snow kits, have had such success that it has been reported that it works even better than traditional aftercooler/intercooler kits due to the injection method and natural octane-inhibiting factor (methanol octane can run in the 120 range in pure form).

A stroker is like any bigger cubic inch engine, it needs more fuel and definitely more air - the more you feed it, the more of an animal it becomes. When you limit it's potential by using undersized parts - obviously you limit power output.

daggar i plan to run v2 sq s-trim....what do you suggest? 302,306,or a 331. what i mean is which one would be the best application.

Daggar said:

If you intend to use the KB that you've already got, I'd suggest doing a 306 with forged rods and pistons and finding a cam and heads that will make the most out that blower.

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Ditto - the 1.5L is undersized for that kind of work.

stock 92 gt said:

daggar i plan to run v2 sq s-trim....what do you suggest? 302,306,or a 331. what i mean is which one would be the best application.

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Don't get me lying. I have some idea of what I'd run with that blower but don't have any practical experience with them. I'll leave your question for someone who knows those blowers much better than I.

I will say however, that given the boost pressures available for the V2 S-Trim that it should run like a raped ape in addition to a 331. Someone who knows those blowers well can confirm or deny that.

Ray@VSK said:

Hmm, so your telling me a 331 stroker with my heads, cam & blower will not give me anymore power but will hurt me more than do good ?

What about if I use a 342 stroker reusing stock pistons, will that maintain my stock compression ratios or be worse because it's a 342 ?

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I don't consider stroking your motor and using the 1.5L KB blower a viable option. You're going to need a larger displacement blower to feed a larger displacement motor.

Daggar said:

Don't get me lying. I have some idea of what I'd run with that blower but don't have any practical experience with them. I'll leave your question for someone who knows those blowers much better than I.

I will say however, that given the boost pressures available for the V2 S-Trim that it should run like a raped ape in addition to a 331. Someone who knows those blowers well can confirm or deny that.

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ok thanks for narrowing it down some and being honest in telling me you dont know all the facts.

Ray most 342 use a 5.4" rod or a 5.315" rod, stock is a 5.09" rod so a stock piston will not work. The CH on a 342/347 stroker piston is usually 1.09 or 1.17, stock is like a 1.6.

The larger blower will be needed to make the power with the increased cubes. A 331, with a good flowing head and intake, custom cam and a S trim (10psi) can make over 500RWHP and still be very, very streetable.

Ray what kind of kit are you looking for? Cast, forged? What cc are your heads?