TPI vs Throttle Body
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From: CT
Car: 86 T/A, 83 Z/28
Engine: 5.0 TPI, 350 2 X 4 bbl
Transmission: 4 speed auto, 5 speed manual
Axle/Gears: 3.23 posi, 3.73 std
Re: TPI vs Throttle Body
There are a lot of pros and cons to both. If you do a search for it youll see a LOT of threads on this very subject. Because of that reason I wont get into great detail just sum it up.
TPI:
TPI was a performance oriented intake that was designed to give better fuel economy. It did just that. It will have better performance better throttle response and gobs more torque. At the time just bolting a TPI motor onto exsisting GM carbed and even fuel injected cross fire motors yeilded roughly a 20% (heard claims as much as 30-35%) improvement in hp, torque, and fuel economy. This is also the most expensive intake to work with.
TBI:
Ment to be a cheap and economical way for GM to produce a fuel injection system. Its cheap and reliable. Although as you can see in 1/4 mile times the 305 TPI motor is much faster than the 305 TBI motor. Granted TBI motors also had terrible heads ect but still it demonstrates my point.
Carb:
The simplest and cheapest of all. A self contained fuel system no sensors or ECM to concern yourself with. Requires tuning and general maintenance (as it is a mechanical thing). Can be pretty cranky if not in good tune especially in cold weather.
TPI:
TPI was a performance oriented intake that was designed to give better fuel economy. It did just that. It will have better performance better throttle response and gobs more torque. At the time just bolting a TPI motor onto exsisting GM carbed and even fuel injected cross fire motors yeilded roughly a 20% (heard claims as much as 30-35%) improvement in hp, torque, and fuel economy. This is also the most expensive intake to work with.
TBI:
Ment to be a cheap and economical way for GM to produce a fuel injection system. Its cheap and reliable. Although as you can see in 1/4 mile times the 305 TPI motor is much faster than the 305 TBI motor. Granted TBI motors also had terrible heads ect but still it demonstrates my point.
Carb:
The simplest and cheapest of all. A self contained fuel system no sensors or ECM to concern yourself with. Requires tuning and general maintenance (as it is a mechanical thing). Can be pretty cranky if not in good tune especially in cold weather.
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Car: 89 Camaro RS
Engine: LO3 TBI
Transmission: 700R4 => WC T-5
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Re: TPI vs Throttle Body
Fuel injection: Better drivability, but requires computer knowledge to make run correctly.
-TPI: Should have been a truck intake in my opinion, emphasizes low-end torque over everything else. Different manifolds are expensive. Injector changes are relatively simple.
-TBI: Cheap switch for low end cars when carbs would no longer pass emissions. TBIs deliver fuel in much the same way as carbs, but allow easy electronic metering for good emissions control. As they're very similar to carbs, TBIs have access to a wide range of carb manifolds through to use of an adapter plate. Trouble comes up with trying to get enough fuel flow for high performance, requires fiddling with fuel pressure and replacing injectors.
Carb: Old technology, requires maintenance, poor emissions performance, ok drivability. Carbs are good on the track, but day to day, EFI is just the way to go.
Personally, I say stick with whatever you have. The effort required to swap from TPI to TBI or vice versa is more than it's worth. The only system I would dump is a carb.
-TPI: Should have been a truck intake in my opinion, emphasizes low-end torque over everything else. Different manifolds are expensive. Injector changes are relatively simple.
-TBI: Cheap switch for low end cars when carbs would no longer pass emissions. TBIs deliver fuel in much the same way as carbs, but allow easy electronic metering for good emissions control. As they're very similar to carbs, TBIs have access to a wide range of carb manifolds through to use of an adapter plate. Trouble comes up with trying to get enough fuel flow for high performance, requires fiddling with fuel pressure and replacing injectors.
Carb: Old technology, requires maintenance, poor emissions performance, ok drivability. Carbs are good on the track, but day to day, EFI is just the way to go.
Personally, I say stick with whatever you have. The effort required to swap from TPI to TBI or vice versa is more than it's worth. The only system I would dump is a carb.
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