350 tbi not enough for a 383?

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hiltijoe

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I spoke w a engine builder about taking my 350 and rebuilding it to a 383 stroker. he advised me that the tbi would be to lean in certain hard running conditions.the 383 seams the way to go for me just concerned about putting the cash in the motor and burning pistons.any advise thanks all
 

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Can use a tbi unit from a 454. Or change to aftermarket fuel injection
 

1987 GMC Jimmy

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You could also have your TBI unit worked by SPR performance. They clean it up, polish it, bore it out to 46 mm, install heavier injectors, and shave the throttle shaft. I think it goes from a 450 CFM unit to about 650 when they get done with it. That's probably gonna be more expensive that the 454 TBI, but it's an option.
 

hiltijoe

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sweet thanks for the info.i found a 454 tbi I'm negotiating now we shat see how that goes
 

roadracerga

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Go FiTeck RBI aftermarket tune to your engine around $1000 or less
 

Daveo91Burb

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I'm building a 383, too (http://www.gmsquarebody.com/threads/383-vortec-tbi-build-thread.17772/). I'm using a 46 mm throttle body and 454 injectors, 74 lbs/hour. The seller's claim on the 46 mm is it can support 330 HP - good enough for me, this build is all about torque. As long as the injectors/fuel pump/etc. can keep up with the air flow there should be no problem with being too lean, the air flow will just act as the power limiter. That is, as long as the chip is tuned properly. If you go this route with original GM TBI, be it 350 modified or 454, I think a custom tune is probably essential.
 

hiltijoe

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I'm now going a different option I bought today a 454 outta a 93 burb I'm gonna build .I'm got the complete unit for 5 bucks
 

Daveo91Burb

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I'm now going a different option I bought today a 454 outta a 93 burb I'm gonna build .I'm got the complete unit for 5 bucks

Wow - sounds like a heck of a lot cheaper than the route I'm taking. I've often wondered if I should have just bought a parts rig with TBI 454 and put that in instead. The only thing affordable about my build is the fact that I've spent two years gathering parts so I could spread the cost out over time. Good luck with the build!
 

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