HP Potential of TBI Setup

Mr Dave · June 18, 2003

What is the horsepower/torque potential of the 95 and older TBI setup? I don't want to get too involved in engine work, maybe a cam swap. But I don't want to change a lot of the bottom end. Need it to be reliable (as it is now) get decent gas mileage, and be good for towing. Anyone have a good combo with a basically stock 350?

Wingnut · June 18, 2003

Cam swap, heads, headers, and a new chip should have you cruising quite a bit faster.

Just make it breathe better, and you will be impressed.

That's my .02 anyway.

americanmuscleman · June 19, 2003

I agree. The heads and cam are the most restrictive things. I picked up a nice power gain swapping my heads and cam.

I would consider a whipple supercharger if I did it again. Stock idle and shift points, decent gas mileage, and you'll make a nice gain in horsepower and torque.

You'll probably see the same hp and torque gains with aftermarket aluminum heads, cam, intake, headers and exhaust, and a custom chip... but you won't have to go through all the work of swapping all that, and you'll have a flatter torque curve and more horsepower throughout the rpm band rather than just at the top end.

Just my 2 cents.

MarkD · June 19, 2003

I too would seriously consider a super charger.

TBI setups are mostly made for torque (which is good for a 4wd SUV).

Are you considering a rebuild/refresh with minor changes?

Matched heads/cam/lifters will give good results. I wouldn't waste time changing the throttle body though.

Mr Dave · June 20, 2003

I am really trying to do as little as possible. I want to get decent mileage, and have enough power to pull up a medium size hill without having to downshift to maintain 70 mph.

It runs great right now, just very little power and not enough to maintain highway speed up a grade without downshifting. I plan on replacing the 33/12.50 15s with 31/10.50's and I hope that helps a bit, but I'm not sure that will accomplish my goal of being able to cruise the highway without the constant downshifting to maintain 70.

americanmuscleman · June 20, 2003

Mr. Dave, thats the same reason I wanted more power. Around town the truck had plenty of power to move it. On the highway it wanted to downshift on even the slightest grade (I've got 3.42 gears, bigger wheels and tires, and a big grill guard). The setup I swapped to picked up quite a bit of low end torque. It didn't pick up as much horsepower as I wanted though. I'm not sure if my computer calibration isn't right yet or what? Anyway, I can pull most hills in overdrive now.

I get about 12mpg in the city, and about 13-14 on the highway. I can get 15 if I go 65-70mph.

I would check out a whipple supercharger though. Nice gains throughout the powerband, and good mileage. It will likely give you the low end power you want for climbing hills too.