What is the Main difference between TPI and TBI? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

camaro_burns_all · 10-19-2009, 12:42 PM

tuned port injection and throttle body injection

ttss · 10-19-2009, 04:19 PM

TBI is basically a high tech carb. The injectors are mounted in the throttle body.

TPI is usually multiport fuel injection. There is one injector per cylinder, therefore more effective. The throttle body controls the air flow. Injectors deliver the fuel flow.

HaveBlue · 10-19-2009, 06:29 PM

Yep what ttss said.
TBI is a wet flow manifold (gas & air)

TPI is a dryflow manifold. (Air only)

I've never considered TBI true fuel injection. As ttss said it's more of an electronic carb. You still have all the issues of cylinder balance.
They do serve as a good carb upgrade for off-road trucks, though.

10-19-2009, 12:42 PM	#1
camaro_burns_all Drives: 04 Pathfinder Join Date: Jul 2008 Location: New York Posts: 49	What is the Main difference between TPI and TBI? tuned port injection and throttle body injection

10-19-2009, 06:29 PM	#3
HaveBlue Drives: CTS/CAMARO Join Date: Jun 2009 Location: SEMA/PERF INDUSTRY GUY Posts: 488	Yep what ttss said. TBI is a wet flow manifold (gas & air) TPI is a dryflow manifold. (Air only) I've never considered TBI true fuel injection. As ttss said it's more of an electronic carb. You still have all the issues of cylinder balance. They do serve as a good carb upgrade for off-road trucks, though. __________________ "everyone wants to go to heaven. but nobody wants to die" "you gotta pay to play" SEMA PICTURES-PARTS & CARS http://www.pbase.com/haveblue/sema_2009

10-19-2009, 04:19 PM	#2
ttss TTSS Drives: 2010 Black on Black SS L99 Join Date: Sep 2009 Location: Cordova TN Posts: 48 View My Garage	TBI is basically a high tech carb. The injectors are mounted in the throttle body. TPI is usually multiport fuel injection. There is one injector per cylinder, therefore more effective. The throttle body controls the air flow. Injectors deliver the fuel flow.