Fuel screw

[Bad93Cummins]

Where is the fuel screw located? Having hard time tring to find it on my 93 Cummins.

[ford69557ci]

It is on the back of the injection pump closest to the engine block. It may have a plastic cover over the screw and it will have a jam nut on it also. There is a metal colar that will need to be removed in order to get max fueling from the fuel screw adjustment.

[Horus]

Say you don't want to remove the collar. Can decent power gains be made turning the screw in till the collar bottoms out or slightly before?

Is removing the collar and turning the screw to full fuel a good idea on a truck that will do a lot of towing?

[peobryant]

Say you don't want to remove the collar. Can decent power gains be made turning the screw in till the collar bottoms out or slightly before?

Is removing the collar and turning the screw to full fuel a good idea on a truck that will do a lot of towing?

Depends on if you have a Non I/C truck or an I/C truck. The Non I/C trucks seem to respond to the fuel screw a lot more then the I/C trucks, so an I/C truck with the fuel screw maxed out could probably tow pretty well, but the same can't be said for a Non I/C truck. They get toasty pretty fast, due to a smaller turbo, no intercooler and bigger injectors.

[Bad93Cummins]

I just planed on turning it a turn or 2 i have a 93 so its intercooled, just looking for little extra power and some smoke. Plan on 4" straight pipe soon and fuel pin.

[Bad93Cummins]

It is on the back of the injection pump closest to the engine block. It may have a plastic cover over the screw and it will have a jam nut on it also. There is a metal colar that will need to be removed in order to get max fueling from the fuel screw adjustment.

Ill have to look agian, cause im having a hard time finding the damn thing.

Thanks yall

[Richie O]

My 93 was almost to the collar when I busted off the anti tamper tin cap. I pulled the screw out and beat off the collar. I worked my way to bottomed out 1/2 turn at a time with no runaway. It increased max boost to 32 psi with the 60 mm GDS compressor. I saw 1200 max temp.

Every pump is different for sure.

[ford69557ci]

If you remove the throttle cable bracket it will be way easier to access. On my non i/c truck it was very hard to see without the bracket off. The i/c trucks will take more turns in than the non i/c trucks when it come to towing. The intercooler the better turbo and the snaller injectors all allow more turns without getting hot fast.

[peobryant]

My 93 was almost to the collar when I busted off the anti tamper tin cap. I pulled the screw out and beat off the collar. I worked my way to bottomed out 1/2 turn at a time with no runaway. It increased max boost to 32 psi with the 60 mm GDS compressor. I saw 1200 max temp.

Every pump is different for sure.

Richie, you get that '93 on the road yet? Have you driven it with the 6X.016's?

[Richie O]

Richie, you get that '93 on the road yet? Have you driven it with the 6X.016's?

Its in need of body work and paint but it's on the road with the 6X16's.
And where have you been?

[peobryant]

Richie, you get that '93 on the road yet? Have you driven it with the 6X.016's?

Its in need of body work and paint but it's on the road with the 6X16's.
And where have you been?

I've been in Florida. I was supposed to have my 370's installed when I got back, but my brother didn't get them to Brian so who knows when they will get done now...

Any pics of the truck as it sits now?

[jonw2540]

heys guys my dad has a 90 non i/c that is now i/c with the i/c setup out of a 93 and has 370s,smokey power pin,1 turn fuel, no timing moved yet, and today after we finished he drove it some and is only hitting 15-18 psi so can he start adding more tunrs to the fuel screw or would grinding the afc lever help he also uses a holley black pump for his lift pump, any help is welcome guys
-Jon

[Bad93Cummins]

Will turning the fuel screw 2-3 turn's will that hurt gas mileage or hurt my old motor?

[TWorline]

Will turning the fuel screw 2-3 turn's will that hurt gas mileage or hurt my old motor?

If you are using gas in your engine the fuel screw is the least of your worries. Before doing much tweaking on your pump you should have gauges installed to monitor your EGTs and boost.

[Kroner]

I turned my fuel screw in to just before runaway and bumped timing and went from 18.5mpg to 17.9mpg. I wasnt driving it easy but wasnt too hard on it either. I dont really think it affects mileage much, but it does help in the power department. Not to hijack but would a dennyt pin affect mileage?