TBI upgrade for an upgraded 5.7

[dlivewyer]

Hey guys, I'm new to the group as well as TBI tuning. I have a '94 c1500 that had a stock 5.7. I recently replaced the engine with a Blueprint 355 (https://www.summitracing.com/parts/mll-bp35513ctc1) dynoed at 390 HP with a holly 600 CFM carburetor that it came with. It has aluminum heads with .202/.160 valves, roller cam and lifters and aluminum intake. I did not want to change to the carb, so I put the stock TBI on it using an adapter plate. It runs pretty good but it doesn't seem happy, I feel that it is wanting more fuel (and maybe more air). I've been told that I need a 454SS TBI. Would this work without having to change the computer? Or could I just replace the injectors with the 454 injectors? If not, what would be the best course of action. Thanks.

[In-Tech]

It's going to need a lot of tuning along with the early 454tb/injectors, a vortec fuel pump and probably will have to go to an 18 or 30lb spring.

[PlayingWithTBI]

It's going to need a lot of tuning along with the early 454tb/injectors, a vortec fuel pump and probably will have to go to an 18 or 30lb spring.

^^^This plus, you may want to go with a 46mm bored TB or the 50mm 7.4L to get enough air flow. Depending on how high you rev this motor, the stock 5.7L TB may not be enough.

[dlivewyer]

What is the part # for the 454 throttle body that i need. I found 1, part #17091045, Is this the right one?

[In-Tech]

I am not sure if this is still available : http://www.gearhead-efi.com/Fuel-Injection/showthread.php?10799-454-TBI-harness-wiring-Moates-ecu

According to ebay https://www.ebay.com/itm/284636880402 That looks like what you want. I just noticed that ad is from some guys across town from me. I have bought some parts from them on occasion with no problems.

You will probably still need to up the fuel pressure from 12psi. They are 75lb injectors at 12 psi, so 150lbs per hour divided by BSFC of .5 is only enough injector for ~300hp
https://www.injectorrx.com/fuel-injector-cleaning-and-flow-testing-service/fuel-injectors/injector-calculators/fuel-flow-pressure-change/

[dlivewyer]

I am not sure if this is still available : http://www.gearhead-efi.com/Fuel-Injection/showthread.php?10799-454-TBI-harness-wiring-Moates-ecu

According to ebay https://www.ebay.com/itm/284636880402 That looks like what you want. I just noticed that ad is from some guys across town from me. I have bought some parts from them on occasion with no problems.

You will probably still need to up the fuel pressure from 12psi. They are 75lb injectors at 12 psi, so 150lbs per hour divided by BSFC of .5 is only enough injector for ~300hp
https://www.injectorrx.com/fuel-injector-cleaning-and-flow-testing-service/fuel-injectors/injector-calculators/fuel-flow-pressure-change/


Would I need all that stuff of just the TBI?