TBI to TPI
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Supreme Member
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From: Baltimore, MD
TBI to TPI
Although I love my car and since I changed from a 305 to a 355 it has been very fast but I understand that my TBI is very restrictive and I still want to go faster. Can anyone tell me what I need(every single part) and what I can reuse from the TBI to go to TPI. Also costs would be helpful too. Also if I could get anything from a junkyard or not.
Thanks alot
Thanks alot
Joined: Jul 1999
Posts: 10,950
Likes: 27
From: Orange, SoCal
Car: 1990 Pontiac Trans Am
Engine: 355 TPI siamesed runners
Transmission: Tremec T56
Axle/Gears: 12-Bolt 3.73
Check the tech section, there is an article written about this.
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1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-
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1991 Camaro Z28
5.7L 5-Speed (originally 305)
13.25 @ 107.18 MPH
Southern California
Member: SoCal 3rd Gen F-Bodies
Webmaster: SoCal F-Bodies
-=ICON Motorsports=-
Supreme Member
Joined: Jul 1999
Posts: 18,457
Likes: 16
From: Loveland, OH, US
Car: 4
Engine: 6
Transmission: 5
You're going to have a tough time getting anybody to post a complete list of all the parts and pieces, there are quite a few to say the least. There's very little of the TBI stuff that you can carry over. You'll need the intake manifold, throttle body, plenum & runners, computer, wiring, sensors, fuel pump, etc.
The best thing to do would be to find a wrecked TPI car, buy it, and swap all the stuff over. The biggest fun will probably be the fuel pump (in the gas tank) since TBI uses about 12 psi and TPI requires about 45 psi.
You will probably come out cheaper and better in the long run by just selling your car and buying one with TPI. If you find one with a 350 you can swap your (I assume) new one into it under its TPI induction system.
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"So many Mustangs, so little time..."
The best thing to do would be to find a wrecked TPI car, buy it, and swap all the stuff over. The biggest fun will probably be the fuel pump (in the gas tank) since TBI uses about 12 psi and TPI requires about 45 psi.
You will probably come out cheaper and better in the long run by just selling your car and buying one with TPI. If you find one with a 350 you can swap your (I assume) new one into it under its TPI induction system.
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"So many Mustangs, so little time..."
I agree with RB on purchasing another car with the TPI. I piece'd together my system over an 8 year time period so I did not notice the cost so much, but ading it all up at the end I figured out that buying another car would have been simpler and cheaper. In another way I am glad I did it this way though because I got to build the car from the ground up so I know a lot more about my car now than I would have otherwise.
Most definitely purchase another vehicle.
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"84Z28/'91 305TPI comp cam flowmaster TB coolant bypass/shutoff valve to heater core MAT relocated Ram-Air(home-made) gutted air-box IROC ground effects/wheels GY245/50's 700R4 superior shift kit/ corvette servo(excellent shift kit BTW) Rebuilt engine and transplanted it myself. Love this engine!
LOW performance people should drive low performance vehicles!
Most definitely purchase another vehicle.
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"84Z28/'91 305TPI comp cam flowmaster TB coolant bypass/shutoff valve to heater core MAT relocated Ram-Air(home-made) gutted air-box IROC ground effects/wheels GY245/50's 700R4 superior shift kit/ corvette servo(excellent shift kit BTW) Rebuilt engine and transplanted it myself. Love this engine!
LOW performance people should drive low performance vehicles!
You might consider another route.
There are quite a few folks on this board running 300-350 bhp TBI-fed 350s.
TPI mods are 2-3 times the price of TBI mods.
Holley makes some 4-barrel TBI units that can support more than 450 bhp.
Check out the TBI board. It might change your mind.
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'89 RS -355, Corvette Heads, Compucam 2050, Holley projection & Manifold, Eddlebrock headers, 3" cat & exhaust, Flowmaster, Hurst, MSD, subframe connectors, etc.
There are quite a few folks on this board running 300-350 bhp TBI-fed 350s.
TPI mods are 2-3 times the price of TBI mods.
Holley makes some 4-barrel TBI units that can support more than 450 bhp.
Check out the TBI board. It might change your mind.
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'89 RS -355, Corvette Heads, Compucam 2050, Holley projection & Manifold, Eddlebrock headers, 3" cat & exhaust, Flowmaster, Hurst, MSD, subframe connectors, etc.
Thread Starter
Supreme Member
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From: Baltimore, MD
Thanks alot for your suggestions, but the only problem with selling my car is that I have about $10,000 other than what the car cost me(literally) in to it. I just had a 355 built and it is running mid 13's (very inconsistent) with TBI and 3.73's, but its starving for more air and fuel and I need something better. again, thanks for your suggestions
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