tbi changing to carb??

Has anyone ever done this swap. I am rebuilding my motor and was thinking about changing to a carb. I have a 88 crewcab sqbdy with a 454. Has anyone done this swap and if so what does it entitle me to do. Any help would be great. Thanks Guys.

ok well im doing the oppisite swap on mine... i have a 80 and im puttin tbi from my 88 on it.... to switch to carb you are gunna need the new intake, new distrubuter and you can loose the O2 sensors in the exhaust manifold. thats all you will need to do the swap.

If you're going to use the TBI pump in the tank, you're going to need a bypass style fuel pressure regulator. Aeromotive makes a nice one, the only one they have with hose barb fittings instead of AN, for about $100 from Jeg's. If you use a regular dead-end style cheapie regulator it'll be hard to set the pressure correctly and eventually you'll kill the pump dead-ending it like that. The bypass style regulator has a return line to the tank like the old TBI setup used. That TBI pump can put out up to 14 psi (up to 32 psi on the '94 model 454 TBI) and your carb wants about 6 psi.

Richard

and if your doing away with all of that your computer wont shift the trans right and the lock up converter wont work thats if you have the el 3spd with overdrive automatic

hey someotherguy I've been doing some reserch on gm style electric pumps and the majority of the TBI pumps run between 12 psi and 30 psi and 19gph to 27 gph but... the pump that goes in a 96 c3500 has a psi of 34 and runs at 43.5 gph so if you running an ajustable regulater on your TBI you can really crank up the pressure and hold it there at wide open. I just changed my pumps out on mine and it woke my motor up

the pump part # is acdelco ep381 and I crossed that over to the delphi witch has a little higher numbers

Pig anything over about 13 psi is just going to try and push open your needle and possible flood the carb. The higher volume may help but higher pressure after a certain point will probably cause more problems.

Pig, a '96 will be Vortec, which will be around 50-something psi for a big block, closer to 60 for a small block. If you're playing with an adjustable FPR on a TBI and want more than the 14 psi or so that most of the TBI pumps give, get a pump for a '94 454. The '94 454 is still a TBI, but while the earlier 454 TBI's ran the same 9 to 13 psi spec that a small block TBI runs, the '94 has redesigned injectors and run at a higher pressure. The test spec on a '94 454 TBI is 26 to 32 psi.

Richard

I have a turbo 400 trans. so will this still wwork or am I dreaming. And if I'm dreaming then could you tell me what to do to make my tbi better.

the th 400 will work with out the ecm
a tbi motor is a fairly easy motor to get power out of because their detuned from the factory
bump up your fuel pressure with a adjustable regulator
a good set of plug wires, high out put coil and a msd 6al spark multiplyer helps and you can also open the gap up on your plugs also
make that f^ger choke on as much cold air that you can physicly force down the throttle body

last but not least have some one that IS GOOD reprogram the ecm

heres some sites
a good place to get tbi parts




here's alot of good reading on getting power out of these motors


heres the guy that I'm going to have reprogram my ecm when I get my truck running agine look at some of the number gains

I'm only running 12psi but thats from idle to wot as were my stock pump I couldnt get more then 10psi and it would drop down to 1 or 2 psi at wot
my understanding is the psi rating is based on the initial hit so you want to look at the gpm also for the amount of fuel it will get

the gm pumps are all the same when you look at them there might be some differances here and there but their all interchangable their differance is how much fuel they push

I don't want to start a pissing match but I know that with the new pumps in my truck its a lot more responsive and its alot crisper sounding and I have a lot better mid range power band now

I thought maybe you were trying to push like 20psi. I've seen guys try it.