tb cpi mpfi

ok, my truck has a tb, ive heard of people talken of cpi, i know tb is a step up from a carb, but not a whole bunch more, what is cpi and will it give me a little more power then a tb? Also is it possible to do a multi port on a 98 4.3L? I was going to do a moter swap, but now im not sure, grandparents are still willing to do the sb for me, but im not sure if its worth it... i know its a stupid question to someone but thanks for taken the time and answern it for me

If you have a 98, you already have Muliport fuel injection, NOT Throttle Body Injection. You use a Central sequential injector. There would be no real benifit to going to fuel rails with individual injectors since you have a sequential system already. TBI stopped in 95 as did CPI... CPI is the predecessor to yours. Very similar injector system but instead of being sequentially fired, it's batch fired, and CPI is still MPFI.

On a side not, look at the 8th digit of your VIN on the driver's side Windshield. Is it a W or an X ?

it is an x, and thanks for the info... never seen a mp w/out a fuel rail, thats why i was confused thinken tb

At this point the only real diff between yours and the W motor is slightly smaller cam and some ECM programming on the fuel curves. Other than than it's the same injection and same motor.

no cam, rocker roller

no cam, rocker roller

What do you mean no cam, roller rocker?

i like the tbi. less headaches, and very realiable. too many problems with cpi, mpfi. what do you mean no cam?

our trucks use rocker cams instead of the traditional cam, kind o sucks, harder to find high preformence cams and a true cam kit is 1400 bucks

Actually our trucks use regular cams with roller rockers.... If you're looking for a more agressive cam, go to comp cams, they make several for our trucks.