I have a TBI 4.3 from and s-10 in my new buggy I am building. Everything I have had before this didn't really matter on power as long as it ran good. For my buggy that I am going to compete in the 2010 We-Rock and Rrock competions I want it to run GREAT!!! What parts should I run to get the most torque and power, to run on pump gas and be very durable and long lasting. I figure I should be good with 250 275 horse as my buggy will weigh between 2300 and 2500lbs. Let me know what you think. Here is a pic of the buggy so you don't get bored. Sorry if this is a dumb questions I am a suspension chassis guy not a motorhead.

http://www.compcams.com/Community/Articles/Details.asp?ID=232019365

You will be hard pressed to get 250 HP out of a TBI inducted mill. The article linked above is carbed. The TBI MAP sensor really limits the cam selection, ect... Even 200 HP is a stretch for a 4.3L TBI.

Just my $0.02...

If you google a bit you can find cams, intakes, and headers, and there's always boring and stroking.

The throttle body on the 4.3 is the same bore as on the 305 and 350, so you should be able to build some good power with one. (Injectors are different) If you think not, there is always the 454 throttle body with larger bores.

http://www.summitracing.com/parts/EDL-3713/

http://www.summitracing.com/search/Make/CHEVROLET/Engine-Type/V6/Engine-Size/4-3L-262/Department/Engines-Components/Part-Type/Camshaft-and-Lifter-Kits/?Ns=Rank|Asc

Thanks for your help I have been searching a bit and have found some parts I am going to talk to the machinist today and see what he can add. I will let you know what i come up with.

I'd go with a vortec head conversion, while keeping your TBI fuel injection. GMPP makes a conversion baseplate for them, but i thought i heard something about the ports not matching up 100%.

Either way, the 4.3L vortec heads need some work to flow as good as it should anyway. A mild port/gasket match should open it up good. If you wanna go full vortec swap and run the CSFI unit, i'd suggest using the upgraded multec 2 injection spider. But the mian bottleneck with that setup is the intake manifold and the injectors themselves.

You can get a marine intake, which would require some fitting to make work but will allow you to swap out for larger injectors if needed. I know it's a great upgrade for the V8 vortec guys and the parts are available for the 4.3L as well.

If that's not up your alley, i'd recommend doing the ultimate TBI mods. injector pod spacer, TB spacer (good only for wet manifold designs), edelbrock manifold (i heard one kid who liked it). Possibly use the 5.7L's throttle body (if it's any bigger for the 5.7L). Run the cam that a previous poster posted.

What you need to do is get those heads flowing good. The 4.3L's got the shaft on the head side of things. I remember reading an article online, where this magazine built a 4.3L and managed to get it to around 300HP without any crazy mods (besides head work and some coin).

Seeing as how this will be a buggy, you can always try to adapt the syclone/typhoon turbo system to your 4.3L as well. That setup stock on those vehicles gave them incredible power and performance for their day, practically causing foreign sportscars to rethink the redneck americans and their funny big trucks.

Thanks for the feedback I have been talking to a friend of mine that pulls trucks and builds all of his own engines. He says that I need to junk the tbi and go for pro-jection or a new MAF engine. he says that cam selection for the tbi is very limited and and probably wont notice a difference from stock. What do you guys think??

Thanks for the feedback I have been talking to a friend of mine that pulls trucks and builds all of his own engines. He says that I need to junk the tbi and go for pro-jection or a new MAF engine. he says that cam selection for the tbi is very limited and and probably wont notice a difference from stock. What do you guys think??

The cam selection for the 4.3L in general is pretty weak.

The valvetrain can be upgraded with any part available for comparable heads on the 5.7L, because it is a 5.7L with 2 cylinders missing LOL.

You can get a custome grind done from any of the big companies to suit your needs, but i do recommend upgrading the heads as well.

As for the TBI, i've seen guys pulling crazy numbers out of TBI engines with tuning. Just do the ultimate TBI mods, upgrade to 350 TBI unit, new TBI intake (make sure that it will work with whatever heads you chose).


I'd go with vortec cylinder heads though, if you've got the time/experience/tools/knowledge, i'd do some cleaning up on the casting of the heads. If you don't then get a shop to do it for you. If you keep the TBI system, tell whoever is doing it that, because it will still be a wet manifold design and the intake ports should be kept rough to better atomize the air/fuel mixture.

It's not so important with a dry manifold system, which is any sort of port injection.

Hey Just letting everyone what I came up with. I decided that a 4.3 was not practical to get the HP I wanted. So I bought a wrecked purple Bonniville SSEI. The 3.8l Super Charged V6 seems to be a great engine with a solid aftermaket and with minor modifications I can be 350 hp. Thanks to everyones help and good luck with your projects!!