Need help with TBI to carb swap
#1
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Car: 1989 Firebird
Engine: 305 TBI
Need help with TBI to carb swap
Hey guys, I'm currently having VATS issues, which brought the idea of swapping my TBI out for a Carb
If i were to do this, is there a lot of work required?
Will i need a different fuel pump?
What other things would need to be removed/ installed?
Any input would be greatly appreciated !
Thanks!
If i were to do this, is there a lot of work required?
Will i need a different fuel pump?
What other things would need to be removed/ installed?
Any input would be greatly appreciated !
Thanks!
#2
Supreme Member
Re: Need help with TBI to carb swap
You will need / get
New pump or regulator
New manifold
New distributor
Less horse power
Less MPG
Less reliability
Why not fix the VATS or have someone burn you a prom without it?
New pump or regulator
New manifold
New distributor
Less horse power
Less MPG
Less reliability
Why not fix the VATS or have someone burn you a prom without it?
#3
Supreme Member
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Re: Need help with TBI to carb swap
Is it a lot of work? No not really. Some fuel line changes, some wiring changes, and the basic intake swap.
No, you can use the same fuel pump. Just have to modify the wiring and add in an adjustable fuel pressure regulator.
What other things? Swap intakes, change some wiring, change the fuel line configuration, HEI distributor, add a pressure regulator.
But again, if it is just because of VATS, I wouldn't do it. If you are stock and just want to swap to carb, then I still wouldn't do it. Fix the EFI and enjoy it.
#4
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Car: 89 Firebird
Engine: 355 TBI
Transmission: 700R4
Axle/Gears: 10 Bolt.Posi-3.73s
Re: Need help with TBI to carb swap
Less Power? No no no. A good carb and intake along with an Hei distributor and MSD ignition on the same engine will make more power than your low performance TBI setup period. Now I will have to agree that the TBI is usually trouble free and very easy on gas. It is in no way form or fashion faster than a well tuned carb setup. Neither is a TPI setup for all that matters. Carb is usually easier to work on and more people are familiar with it and willing to help you. *In saying all that I think you would be more happy with the TBI setup it is a reliable system and good on gas. A chip burner can take out that VATS for you and even give you a lil performance boost if that's what you want. Even with a carb setup it wouldn't be a speed demon anyways.
Last edited by dmccain; 06-23-2015 at 07:49 AM.
#5
Supreme Member
Re: Need help with TBI to carb swap
If you spend a few hours on the dyno and install some decent A/F meters you might be able to get an extra peak HP or two but the chances of actually tuning the carb vs slapping on a cheap edelbrock and maybe adjusting the screws are next to nothing for the average person. Either way the intake system is not the restriction on the TBI motor it is the shitty little cam. After that you could probably toss on a performance carb and get more HP amusing you were not willing to do the same for a TBI system.
#6
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Car: 87 bird
Engine: enough to break stuff
Transmission: manual th400
Axle/Gears: 4.10
Re: Need help with TBI to carb swap
im a carb guy but i agree its not cheap or easy, it is much cheaper and easier to bypass the vats. they have 50/60 hz replication chips all over and that bypasses everything if you solder that into the pcm. you just have to bypass the start relay. the resistor deal only bypasses the key. or you can get it tuned out, not sure what that costs but probably costs a few hundred to 6-8 hundred to put decent carb and ign stuff once you buy all the adapter stuff, regulator, hoses, and crap
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