350 to 383 stroker
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Pro
Joined: Jul 2002
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From: Flower Mound TX
350 to 383 stroker
I'm currently having my 350 build into a 383 stroker, I'm keeping my orig. heads and cam , just building the bottom end, keeping the same compression. Will I see a increase in HP and Torque or just Torque
Instructor
Joined: Mar 2002
Posts: 120
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From: Bedford TX
Re: 350 to 383 stroker (robtx)
I'm about to rebuild my motor as well and have been considering stroking it. My engine builder is concerned about drivability with the 383, but I've seen some impressive #s posted by guys who have done this. I'd be interested to see what folks have say. Is your builder planning to re-program your computer? I think most folks will agree that the secret to building power with the LT1 is in the heads and cam. Even stock LT4 heads and a GM hot cam should provide somewhere in the neighborhood of 80hp over the stock LT1. I saw someone had both peices and roller rockers listed for $500. In for a penny? :cheers:
Drifting
Joined: Dec 2002
Posts: 1,861
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From: Houston TX
Re: 350 to 383 stroker (S & K Dunn)
Well, as an answer to the first question, you're going to see an increase in both. Keep in mind that horsepower is the rate at which your motor produces torque, so if you increase one of the two at a given rpm, you have by default increased the other.
The driveability of ANY motor is a function of the heads, cam, and intake selection. The guys on here that have build the 427 small blocks can build one that makes 800 horsepower, idles at 1300-1500 rpm, and makes little horsepower below 4000 rpm, or they can build a smooth idling 500 horsepower motor that will pull plenty of vacuum to support power brakes and other stuff without a reservoir. If your engine builder is ANY good at selecting parts, he should know that he can select component to make the motor do just about anything.
The driveability of ANY motor is a function of the heads, cam, and intake selection. The guys on here that have build the 427 small blocks can build one that makes 800 horsepower, idles at 1300-1500 rpm, and makes little horsepower below 4000 rpm, or they can build a smooth idling 500 horsepower motor that will pull plenty of vacuum to support power brakes and other stuff without a reservoir. If your engine builder is ANY good at selecting parts, he should know that he can select component to make the motor do just about anything.
Team Owner
Joined: Sep 2001
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From: Athens AL
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Re: 350 to 383 stroker (robtx)
Youll get more of both, but itd be a shame not to replace the cam while you have the motor out.
Safety Car
Joined: May 2003
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From: Houston Texas
Re: 350 to 383 stroker (robtx)
I think he has already replaced cam with a crane example not to mention LPE heads and intake and 58tb. Lpe seems to get another 40 hp not to mention more torque due to displacement increase. No substitute for cubic inches!!!
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Pro
Joined: Jul 2002
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From: Flower Mound TX
Re: 350 to 383 stroker (BAM92)
I think he has already replaced cam with a crane example not to mention LPE heads and intake and 58tb. Lpe seems to get another 40 hp not to mention more torque due to displacement increase. No substitute for cubic inches!!!
Pro
Joined: Oct 2001
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From: loxahatchee fla
Re: 350 to 383 stroker (robtx)
with no other changes but the increase from 350-383 displacement its very comon to see a 30-40 ft lb increase in tq over most of the rpm range
since the formula for hp is (tq x rpm /5252=HP)
lets assume a stock tpi at 330ft lbs /3800rpm = 238hp
adding 35 ft lbs would give 365 x 3800rpm=264 hp but of course adding a cam with slightly increased duration would take better advantage of the increased displacement, and porting or replacing the intake with a better flowing unit would further increase the gains at least slightly, getting 300 hp from a correctly built TPI 383 is not all that hard!
porting the stock intake, a pocket port job on the cylinder heads and a cam in the 215-220 intake duration range will normally get you there (300hp)
[Modified by grumpyvette, 3:11 PM 6/10/2003]
since the formula for hp is (tq x rpm /5252=HP)
lets assume a stock tpi at 330ft lbs /3800rpm = 238hp
adding 35 ft lbs would give 365 x 3800rpm=264 hp but of course adding a cam with slightly increased duration would take better advantage of the increased displacement, and porting or replacing the intake with a better flowing unit would further increase the gains at least slightly, getting 300 hp from a correctly built TPI 383 is not all that hard!
porting the stock intake, a pocket port job on the cylinder heads and a cam in the 215-220 intake duration range will normally get you there (300hp)
[Modified by grumpyvette, 3:11 PM 6/10/2003]
Burning Brakes
Joined: Apr 2000
Posts: 959
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From: Lemoore CA
Re: 350 to 383 stroker (grumpyvette)
Or you could get a little work on the stock heads, LT4 hot cam, and an intake like the SuperRam with headers to boot. Thats what I did and loved the results, but never underestimate the power of TUNING, cuz I imagine no 383 setup will run very will without some major chip work.
Paul
Paul
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Safety Car
Joined: May 2003
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From: Houston Texas
Re: 350 to 383 stroker (robtx)
Okay he has a lt1 that started life with 300hp already. With the original mods and programming he probably was making 4-410 hp. With displacement increase and redo already custom programming should get to atleast 450 hp depending on cam.
Burning Brakes
Joined: Aug 2000
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From: Albuquerque NM
Re: 350 to 383 stroker (robtx)
You will not see an increase in HP...Since you are not changing anything relating to air flow.
You might see an increase in efficiency just due to the fact that you are "building" a motor.
Your torque curve will move down to a lower rpm range.
Suggestion: Get rid of the wimpy cam and go get a compcam xtreme roller hyd at 218/224 ground on a 112 lobe sep. Bigger is badder though
Start saving money for your heads -> $2000
Start saving money for your intake -> $1800 (increase cam duration for miniram or stealth ram)
Start saving money for full exhaust -> ??????
now reprogram your computer
or just leave it stock and be happy
You might see an increase in efficiency just due to the fact that you are "building" a motor.
Your torque curve will move down to a lower rpm range.
Suggestion: Get rid of the wimpy cam and go get a compcam xtreme roller hyd at 218/224 ground on a 112 lobe sep. Bigger is badder though
Start saving money for your heads -> $2000
Start saving money for your intake -> $1800 (increase cam duration for miniram or stealth ram)
Start saving money for full exhaust -> ??????
now reprogram your computer
or just leave it stock and be happy
