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mech pump fuel turn up

chevyCowboy

chevyCowboy

I might be crazy but i ain't dumb
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Springfield Nebraska
ok i had a set of directions on how to turn up the fuel on my truck from a different site but i cant seem to find them so dose any one have a detailed instuctions on how to turn up my pump or can anyone tell me how to or direct me to an old thread i tried seaching but didnt find a darn thing
thanks
 
I go in from the top with a ball ended 5/32" allen wrench.

Just pay attention putting the top cover back on, they say you can mess up, but I've never had a problem. IIRC correctly, the top cover will have to slide forward, after it is set back on the pump if its in the right position on the fuel solenoid. You'll see how its suppose to go when the cover is off.

Just in case, leave the turbo/manifold hose off, have a helper crank the truck up while you stand there with board to cover/choke off the intake if it runs away. Being a five speed you could prolly just dump the clutch in fourth gear to kill it.
 
May wanna back the timing back down, your fuel will be more advanced after turning it up. You increase the pumps stroke, so it hits the cam ring in the pump sooner effectively advancing the timing.
 
how far can i go iv hear no more than a 1/4 but a friend of mine has his cranked way up and i havent seen it but iv been told that he can do 0-60 in like 7 or 8 i think he went like a half turn but hes crazy

so which way is easier from the top or the side??
 
The top is way easier,I say easier, I've never done one from the side(I took one look and with my big hands, I said heck no). Its just more fool proof by going in from the side. You must have a ball ended allen wrench to get to it, its at a slight angle going in from the top.

Which ever way you go, use a high quality raw steel(not chrome) allen wrench.

Mine is cranked all the way. IIRC, most dont turn much more than a 1/4 turn before they bottom out.

Dont forget to up the boost some and watch the pyro.
 
ill have to take a look at which way. what all do you have to remove to get at it from the top?

my wastgate is wired shut iv been meaning to make a maunal wastegate but i keep forgeting to get the measurements so i can do it at work one of these days
 
You can run 15psi from the GM3 easy enough, I run my GM4 to 17psi in extreme load/speed cases, 13 psi sustained regularly. IATs jump up there, but as long as ECTs and EGTs are in tolerance its all good.
 
even with it wired all i can get is 12 or maybe 13 i thkn i saw 15 once but the egts where geting to close for comfort so i let off
 
what plowboy was eluding to, youre turning up fuel, so more fuel equals more exhaust pressure equals more boost to a wired shut wastegate. So youll see more boost if you turn up fuel.
 
I may be wrong, but I think you reach a plateou where you are putting unecessary (over-boost) which is causing cooler EGT's sure, but at a dramatic economy loss?
 
josh, my gm-3 is wired almost completely shut. i am hitting around 20 lbs, and under extreme tow loads, have hit 25. but, you can't hold higher boost with these turbos for long as the egt's climb to fast. pulling 6,000 lbs up a hill in winter at 65MPH i kept 20 lbs okay, but hitting 25 for more than 8-10 seconds brought temps up sharp. maybe the best course of action is to figure out a really good air intake system?
 
I think there is a large misconception about how boost will help you if you can't add enough fuel to back up the added airflow, not to mention the extreme inefficiencies of the GM-X turbo's to make anything past 10-15psi of boost, (which is plenty for our IP's and engines to handle).

If you aren't adding more fuel into the mix and WG wired shut, you are essentially making the engine work harder to make more boost, well out of the GM-X efficiency range, compounding the problem.

Now you have the issue about EGT's climbing, where boost is supposed to keep them down, but once out that efficiency range, the HP graph starts to drop fast.

Must keep all addictions "In Moderation" - Pun Intended :)
 
i undrestand the theroy behind boost and fule i wired it with in the first 2 weeks i had it and have never gottin around to turning up the fule im going to do it finally i should have done it along long time ago but things get put off and i was kinda waiting for new injectors but sence im going to do those with the rebuild i figured why not just do it now
 
:
Acesneights1 said:
Anything over 14 psi with stock compression ration is asking for problems.
Click to expand...

We keep on seeming to have these points we disagree on. :D I have been hitting well beyond 14 for almost 10 months now, with no issues. Not to mention, Heath runs higher than stock compression, while putting out a lost more boost.

Agreed you need to turn up the IP to make sure that you are making use of the boost. Even with the boost up, I am still making black smoke under WOT.
 
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