TBI spacers

[JAW's]

I have a 1995 k1500 extended cab. I rebuilt the motor with flat head pistons and the biggest cam I could find for computer controlled motor. The motor still has the stock bore (Due to my dumb ass and a college budget neglecting to bore it out while I had her apart) I put shorty headers on as well. I have a 3" suspension lift and 16x10 pacer wheels rapped in 305/70/R16 BFG Mud Terrain KM2s.

I have been looking into TBI spacers and was wondering if they work as well as portrayed or if the gains are worth the money. Also, if worth the money what is the best style (smooth, slotted, swirled, etc) and brand to go with.

 

[kn1ght]

I had one on my other truck, and I could hear mine, but there wasn't a ton of performance gains. But.. All in all, I would buy another one. I just haven't really gotten around to it. Mine was swirled, I think that's why it was so loud. Mine was like $100 I believe.

 

[WFO4X4]

boreing a motor 30 over isn't going to really add that much. you're talking about such a small amount of ***********. however, if it would have smoothed out some bad cylinder walls.... yeah, bad move. but, it'll need to be rebuilt eventually and you can do it then. and as far as the TB spacer goes.... you could do a 454TB swap and i hear that is the better route to go.

 

[kn1ght]

Doesn't matter. Heads are still restricting flow.

 

[WFO4X4]

well, yeah, but any sort of gain reachable is going to come from increased flow and a larger bore tb will do more to open it up than a spacer that just adds abit of drop.

 

[kn1ght]

Yeah, but you can add as much air/fuel as you want, the heads restrict flow, so I wouldn't change the TB until the heads are replaced.

 

[Mysilvi]

Yeah, but you can add as much air/fuel as you want, the heads restrict flow, so I wouldn't change the TB until the heads are replaced.

Exactly...air will only flow through the largest opening. Big in Restricted out= money wasted. I did put one on mine due to having the Vortec heads still really dont see much HP gains at the wheels, just sounds better when opening it up.

 

[outalne94z71]

Exactly...air will only flow through the largest opening. Big in Restricted out= money wasted. I did put one on mine due to having the Vortec heads still really dont see much HP gains at the wheels, just sounds better when opening it up.

you really don't need to change the heads if you already have vortec heads,those heads are a fast burn design and the runners are designed to flow the charge faster, the problem is if you go bigger tb and intake manifold and don't match the head runners to the intake so everything is flowing smoothly you won't see much improvement because the head runners will have that lip to it from the intake to the head disturbing the charge, now if you clean that up you should see a difference even if the runners are slightly smaller down deep.
if i remember right the exhaust ports are raised on vortec heads which gives better flow without opening the ports, been a while since i dealt with small blocks.

won't be as nice as extrude honing everything to open it up but since we are not talking all out racing that would not be a good economic choice anyway and if you get that far then there is so many other things to do like adding compression and switching to aluminum to help with weight and detonation and on and on.

as far as a tbi spacer goes, i think they are a waste of money i personally wouldnt bother with them and spend that money elsewhere.

 

[Blue95]

TBI heads are fine, great for low end torque and good MPG.

A TB spacer is a great addition!!!! get the cheapest one you can find with SMOOTH bores and get some fuel line extensions and enjoy.

EDIT: also a 454 TB is unneeded because the bores of the intake manifold are smaller then the bores of the TB so there is no gain, a stock 350 TB is good for 400 HP

 

[90chevstepside]

TBI heads are fine, great for low end torque and good MPG.

A TB spacer is a great addition!!!! get the cheapest one you can find with SMOOTH bores and get some fuel line extensions and enjoy.

EDIT: also a 454 TB is unneeded because the bores of the intake manifold are smaller then the bores of the TB so there is no gain, a stock 350 TB is good for 400 HP

Let me ask you something. Your trans is the 700r4 right? How did you get the passing cable to set right? I put a tb spacer in mine and now the torque converter won't lock up on the highway and my gas mileage took a bigger dump than it already was.