CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

What kind of power to expect TBI?

jimmy'sjimmy

1/2 ton status
Joined
Dec 22, 2001
Posts
130
Reaction score
0
Location
Greenwood Village, CO
i am planning on rebuilding my motor in the jimmy. what kind of numbers could i expect with these kind of parts?
.30 over rebuild kit flat pistons
272/282 .442/.465 summit cam and lifters
vortec heads
vortec intake
msd ignition box
same tbi unit
Any suggestions? i dont have a big budget so im taking my time part here part there but i think this would be a nice upgrade over the 170,000 mile motor in it already.

ohh yeah i have 3.73s with 36in PJs but i plan on putting in some 4.56s and some 40s.
 
Beings you are on a budget Heres a few things to think about.
Yur going to have a hard time getting that combo of parts to run right with stock TBI. You will need to have to spend some time on a dyno and have a custom chip burned to make it run right. Usually costs around $600
Flat top pistons and Vortec heads will give you a high compression ratio. Will the cam you are getting work with aprox 10 to 1 CR? Also If I am reading those numbers you posted right you are beyond the limits on lift that will work on vortecs without machine work. .450 is max lift and even that is pushing it.
The stock TBI unit will only support about 280hp. The engine you are trying to build will be capabale make quite a bit more than that. You will need a bigger TB and other fuel system mods to get the most out of it.
You will need a vortec to TBI manifold also $300
If you are on a budget your best bet is to build a computer frendly engine that will work with your stock ECM. Put your money in a Set World 76CC (with flat top pistons) centerbolt torquer heads. Mild computer frendly roller cam set up, adjustable fuel pressure regulator and an aftermarket chip. and you will end up with a very nice running TBI engine.
Before building a computer controlled engine you need to do some research on what will work. Or you will spend a lot of money for nothing.
 
Save up for the good parts now.

64CC heads with proper pistons can result in 9:1 compression, that's what I'm running.

If you are talking about getting into burning your own chips, great investment for later mods. If you mean a hypertech chip, etc., absolute 100% waste of money.

I'd stay away from Vortecs, but you do want a "fast burn" chamber of some sort. Plenty of manufacturers out there making similar for right around the same money. If you leave your options open as to head design (CC in particular) then you will more than likely be able to get pistons to match, that will give you a desired compression ratio.

Stock TBI heads are good at what they were designed for. Bottom end power. Absolutely suck in every other regard. Compared to *modern* designs though (Vortec, etc.) they suck in every single regard. I wouldn't waste dollar one on stock TBI heads for an engine build that I wanted even a little upper end potential on.
 
i've got the bottom side of the tbi

vortec heads, intake, melonized distributor gear, the exhaust manifold with the air tube, etc. shipping would be silly, but if you are anywhere near houston maybe we could work something out when/if you get ready to take the vortec plunge.

i never managed to collect anything above the manifold.

turbo city has the complete package, but it isn't cheap. i'm thinking it was around a grand?
 
what heads do you think would work best and what rebuild kit? I still have not taken apart the motor so i have plenty of time and i have a new truck so i have plenty of time to save up. i am trying to get plenty of advice from all of you who have gone through all the bugs so i dont have to waste money i dont have lol. would a tbi to carb sawp be another can of worms? it just seems like this stupid TBI ruins everything. what if i put vortec heads with dish pistons and a smaller cam? i really want to build this motor but just really confused with this tbi stuff.
 
Top Bottom