So i have a 1991 s10 blazer th 4.3 tbi.What can I do performance wise to get the best performance for the money?Like should i go headers and exhaust first..new carb?give me some ideas i just want to be a little faster.

 

Have you read many posts here? The subject has sure been discussed many times.

 

wasnt the 91 TBI fuel injected? not carb'd? You could start easy with checking junkyards for vortec or syclone heads, from there i would go to better intake setup and head back exhaust. the head adds a easy 30 hp crank and is a stock bolt on (basically the stock head with a port job) and allowing the engine to breathe better never hurts. and though i have mixed feelings about them - throttle body spacers are about 50-60 bux and i have seen reports of up to 20 hp gains. just to think about, take or leave it

 

Thanks for the info,i didnt really search all the threads sorry =(.As far as TBI being fuel injected.Its a carb with two fuel injectors on top of it...Its like carburated/injected.Kinda weird but works great.I think im going to do headers and full exhaust along with a 4 barrel carb and an intake.Vortec or Cyclone heads?Just curious why.

 

the vortec/syclone head wont work, its fuel injected. I thought that the TBI was FI cause my old 91 S10 had the TBI on the Vin letter but it was a FI system. But had it been an FI system the Vortec head was simply put an upgrade to the original by it being a stock head the GM redesigned to have larger ports and such - in other words, cheap way to get a better flowing head job for your truck, and the intake manifold it came with, at least in 94, had tubular ram horn style manifold. But it was a 30-40 hp increase for some parts at the junk yard.

 

TBI=Throttle Body Injection. It is fuel injection. The two injectors sit in the throttle body which looks like the bottom half of a carburetor.

 

There's nothing wrong with FI, but I'm old school. I've had the same idea that my 89 was carbd, untill I read this post. With such a simple FI system would it be a difficult conversion to carbd? Like I said, I'm old school and like to toy with carb settings.

 

thats what i thought though. I know my TBI was FI'd. But who knows what you can find know of days.

 

You don't want to go with a carb. The computer that controls the emisssions, choke, 02 censor, etc, etc, will get all screwed up. Besides, the computer that controls the fuel keeps the mix of air to fuel ratio at a perfect 14:1 ratio. (I think it's 14:1) Any way the computer keeps the performance at it's peak automatically, that means more horse power and better fuel economy. That's what makes injection so much better than carbs. That's also why you don't see any vehicles manufactured with carbs any more. My $.02, take it or leave it.