454 tbi upgrade

[danman6677]

Hey guys just looking at a 454 tbi upgrade for my 88, what is in volved with this job and does it give noticable gains?

 

[low4x4]

if you are adding a 454 tb to a 350 setup...you will have to rewire the tps and the iac...as far a noticable gains...depends on what mods you are going to put on...my setup with a ported 454 tb on a supercharged 355 worked out well

 

[outalne94z71]

if you are adding a 454 tb to a 350 setup...you will have to rewire the tps and the iac...as far a noticable gains...depends on what mods you are going to put on...my setup with a ported 454 tb on a supercharged 355 worked out well

doesnt the 5.7 iac just thread right into the 454 housing?, id have to go out and look at mine but i could have sworn the tps from the sbc base will swap to the bbc base

 

[outalne94z71]

Hey guys just looking at a 454 tbi upgrade for my 88, what is in volved with this job and does it give noticable gains?

anytime you open up a bottleneck you need to open everything else up to utilize it, you may gain a slight bit just by swapping bases but probably not enough to measure on the butt dyno without doing any modding to the rest of the flow.

its just like buying a bored out sbc tbi, doesnt do much good if you are using stock restrictive heads and intake or exhaust

 

[fun4me]

You will have to bore the intake. The 454 tb blades are 2" & the 350 tb blades are 1 13/16". I have one with the wiring adapter for the iac. PM if you are interested in buying.

 

[GMstrong]

I dont see the purpose of this on a stock motor,Like said above,I would bore out the stock tb and put a carb intake or holley projection intake manifold on it.

 

[outalne94z71]

I dont see the purpose of this on a stock motor,Like said above,I would bore out the stock tb and put a carb intake or holley projection intake manifold on it.

boring the stock tb is pretty much the same thing as swapping to the 454 tbi base

the cost difference is the reason i would think the 454 one is a better idea

 

[454SSguy]

It's not a step backwards, that's for sure. But like they said above, the only way to get all you can from it is to feed it with more mods. Best thing you can do for the money would be a nice single plane carb intake and a new TBI adapter. If you throw in a new cam too, you'd see quite a good bit of difference. I think it'd be worth the money, those intakes can be had for cheap ~$150, and the TBI's even cheaper. Might take a little tuning to get it right, but I'd say it'd be worth it. Just my .02 btw.

 

[copernicusd]

i bought one off craigs list, wasnt a direct swap
it was a off a 94 he said, and the plug for the iac was different from my 95, and the 95 one threads in, the 454, uses torx screws to hold on, so i didnt end up using it, not sure where to get different plug ends other then the junkyard

 

[low4x4]

you can order them new from gm...i don't have the #'s...but they do give you plenty on wire to splice them in