My 97 seems to run better at part throttle than it does at full throttle. It kind of levels out and starts a kind of stumble at about 2700 rpm's. The truck used to go up to 3500 rpm's real easy. What would cause this kind of problem, could a fuel filter cause this?

 

A fuel filter might cause it. How many miles since you changed it? Maybe the timing slipped a little.

 

I bought it about 15000 miles ago and haven't changed the fuel filter yet. Guess I'll try that first, I just noticed it today. Do you change the filter the same as the 24v? What about getting the air out of the system? I'm illeterit on the fuel system on a 12v motor!Any help would be appreciated.

 

rpms sound high. my buddys 95 shifted a little over 2000. hopefully its just a filter. i may hit 2700 in mine (24v) but i dont stay there, certainly not 3500

 

I take it up around 3000 to 3200 usually when I'm playing but to shift quick enough in the first two gears is hard. 3500 is probably all it will turn as it just levels out there. I do have 4000 rpm governor springs in it too but I don't have the heavy valve springs in it yet.

 

It must have a 3000 spring kit in it ? anyone.................who knows more than I

My 97' "defuels" around 2400

 

No, its got the 4000 springs I put them in. The truck was uptouched at 235000 when I bought it. Didn't even have a fifth wheel ball in it. I think it stops at 3500 cause its out of air and probably camshaft.

 

Nah. There are guys cranking out 700+ hp to the wheels with the stock camshaft revving to 4000. There are several guys with way less power than that cranking it up to 4000 with the stock cam. Something else is wrong.

 

There is two things that are limiting you.

1)_ timing You need to push up to about 17-18* to get full use of your GSK. If somebody has a smaller pump like my 175HP pump then you will have to break 20*

2) Check you fuel pressure from you lift pump. I have replaced 4 of them this year for guys who had bad one(YES 12V PUMPS GO BAD)

That should help you out.
DM01

 

Check your throttle cable linkage and cable mine was stretch and falling apart.i was not getting full throttle.

 

What fuel pressure does a 12v run and where do you hook up at to check it? I'm going to change the filter tomorrow night I know it can't hurt it. Timing is whatever it is stock. I'm going to change timing as quick as I can get my buddy to help me which maybe sooner than he wants if it slipped the time!

 

Mine is modified a little and I get almost 30. i don't know what stock is because I checked mine and it was around 7psi.

There is a line that rund from the fuel filter to the side of the pump with a banjo fitting.

What I did was buy a new overflow valve and find a fitting that will fint into the hole on the top of it then attach that with some rubber hose to a cheap oilpressure guage. it jumps a little but works great.
DM01

 

Thanks for the info, I'm going to change filter first and if it isn't plugged I'll check the fuel pressure next. Those are the two easy ones.