The Stovebolt Site Forums The Shop Area Engine Shop fuelinjection on 316 pontiac

I have a 316 ci pontiac engine in my 56 GMC. The gas mileage is 12mpg. Any one adapt a fuel injection of some type which would increse mpg and performange in general. thanks

I have worked with both these companies and would recommend them both.
http://www.fuelairspark.com/

http://www.hotrodlane.cc/ look at the TPI installs on there page ,they also have many other fuel injection types to use.

there is Borla Induction, (used to be TWM) I've never used them, but the reason I keep them in mind is they have individual units.

Fixing the carburetor costs 10% as much.

Often truck engines are set up with small passages in the intake and head (higher air velocity adds low end torque). Additionally, the rear end gearing is not MPG-friendly.

It is quite possible you could spend a sizeable amount on a fuel injection system and still have a truck which obtains 12 MPG.

Passenger engine heads, intake, and 4-barrel carb MIGHT help a little on fuel economy, and WOULD help performance. An overdrive transmission should help both.

In any event, should you do the math, probably nothing you do will sufficiently increase the fuel economy enough to pay for the modifications.

Jon.

Running a 59 Pontiac 389 which has been bored and stroked to 447 in my 59 gmc 1/2 ton longbed. Engine was a mild build. I have 3.70:1 gears and a 27% OD transmission. Gas mileage is still about 14 mpg at freeway speeds. I get about 10-12 MPG when I hotrod around and open up the other 2 deuces.

When I first put the OD transmission in, it was behind the 336 gmc engine. Mileage was not improved. I got 10-12 MPG with the factory 4 speed, and the same with the OD. The mileage did improve with the freshly rebuilt 447. I suspect my mileage woes with the 336 were due to a worn out Stromberg ww carb.

Boy would I like to see a picture of that 389 in your truck, bigbadswingdaddy! Can you post something?

I've got a Pontiac 455 overbored to 465 in my '68 Firebird and get a very similar 13 mpg on the highway cruising on 3.08 rear end gears. Yes, a bit tall, but the motor has the torque and it doesn't feel tall at all.

Anyway, back to the original question, did you look into Accel and Holley for their TBI fuel injection systems? There is an advantage. Fuel mixture is always correct, at any altitude. I might make the change myself on my Firebird. Their EFI systems are a little over a grand, if I remember right. Check Summit Racing.