1991 350 tbi to a modern efi upgrade

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Siopao

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Hello! I have a 1991 c1500 with the 350 tbi on it and I just ordered the aces 4bbl efi setup. It came with everything I need and now I just need a manifold for the 4150 throttle body. Was just wondering what would pair well with it for stock performance or slightly higher? Any recommendations would be much appreciated!!!Everything on the 350 is stock.
 

Schurkey

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Good luck with the EGR.

Will that computer control the torque converter clutch? Assuming, of course, that you aren't running a manual transmission.

You're braver than I am. No way would I replace an OEM-validated EFI system with a low-budget (Chinese-sourced?) injection system.
 

Scooterwrench

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Good luck with the EGR.

Will that computer control the torque converter clutch? Assuming, of course, that you aren't running a manual transmission.

You're braver than I am. No way would I replace an OEM-validated EFI system with a low-budget (Chinese-sourced?) injection system.
Yeah, I'm with Shurkey on this one. You could have made the factory TBI run really good. Just upgrading the ECM to the 93-95 PCM would have made it run better.
 

Siopao

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Good luck with the EGR.

Will that computer control the torque converter clutch? Assuming, of course, that you aren't running a manual transmission.

You're braver than I am. No way would I replace an OEM-validated EFI system with a low-budget (Chinese-sourced?) injection system.
I’m very new to the gas world, I’ve mostly only worked with diesel, Cummins to be specific. I was recommended from a buddy at work to try out the aces brand. So far the kit seems to be very well put together, it has everything other than the manifold but they do say you can get a spacer instead of a new manifold. I’m not totally sure if it’s assembled in the USA with parts sourced from china or if it’s all from USA but I took a gamble on it because the holly was a bit more for sure. The tbi is shot on this truck and I didn’t wanna get a used one to play with so I figured I’d go with a more moderns system. I was thinking one of the Derick performer manifolds would work well, I’ll share my thoughts on this when I have it together but just looking to see what the Chevy people could recommend because they know a lot more than me!
 

Sean Buick 76

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Any dual plane intake should work fine however unless they are ordered specifically to control the transmission that will be an issue for you. They offer a trans controlled setup but it’s an extra $500.
 

Siopao

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Any dual plane intake should work fine however unless they are ordered specifically to control the transmission that will be an issue for you. They offer a trans controlled setup but it’s an extra $500.
I’ll look into this, I’m not sure if the Trans is controlled with it.
 

Schurkey

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I’ll look into this, I’m not sure if the Trans is controlled with it.

Will that computer control the torque converter clutch? Assuming, of course, that you aren't running a manual transmission.
A TH400 would have the kickdown controlled by the ECM, but a 1500 woudn't be likely to have a 400. I'm assuming 4L60/TH700.
 

Scooterwrench

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they do say you can get a spacer instead of a new manifold.
Yeah, they're full of BS. You can't put a four barrel TB on a two barrel manifold with an adapter and expect it to perform. Edelbrock makes a dual plane intake that has the correct angle for the four center bolts but here's another problem you're gonna have, the swirl port TBI heads suck or actually I should say they won't suck air. I learned this the hard way on a 79 Malibu I used to have. V6 blew up, dropped in a 355 bottom that I had saved and scrounged a set of 1.94 TBI heads for it and used the Edelbrock dual plane spreadbore manifold for those heads. It ran great!,,,,,,,,,,,,till 4400 RPMS then it was like pushing a wall. I wound up having to pull the heads back off and grinding all that swirly ramp out and opening the ports up under the seats and then they were only a little better, I could get it to pull up to 5000 before it hit the wall again.
If you're gonna run that four barrel TB you will need to get better heads and cam or there's no use.
 

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