My signature says what I have. But how would my truck run if I changed it back to stock plate and 4K spring kit kept everything else?

So it would be.... 15.5 timing, 80 HP injectors, stock plate full forward and 4K? Would the 80 HP injectors give me an issues with a stock plate?

thanks....

Dave

 

You shouldnt have any issues, it just wont run as good. Why are you doing this? To help fuel mileage? Buy a Valet switch, and use it to cut the power up and down if that is what you are trying to do.

Eric

 

Eric my truck runs excellent. But even with my valet switch I have high EGT's when I tow. Just trying to get a happy medium that will keep my head gasket happy..... I have doing another HG right now. It only lasted a year with studs.... I had a shop do the HG last year so it might have been a bad prep job from them. I found out the hard way that they where a shady shop.....

 

Just get some orings cut while the head is off & no more worries.

 

I wouldnt think your truck should be getting all that hot towing. Does it still have quite a bit of power in valet mode? Stock turbo, right?

Do you think you would have it how you wanted if the valet switch would cut the power down more?

Eric

 

Stock turbo and even in valet mode with AFC screw in the middle I can peg the pyro if I am not careful. I can tow on flat ground fine. But any slide grade and the pyro stays to hot for me... I made my 100 plate. Maybe it is more than a 100?? I will just drop my #8 back in go with it....

 

What exhaust housing do you have on your truck??

 

4" turbo back with a Magnaflow Muffler. Is that what you mean by exhaust housing?? Maybe it's time to have no muffler? Or go 5"

 

Before you go to swapping plates, take the cover off the back of your AFC housing, break loose the 10mm locknut, and loosen the allen head bolt a good ways out, and tighten the locknut back up. This will make your valet mode a whole lot weaker, which should translate to lower EGT's. I can make my truck a dog to drive if I want. The cover on the back of the AFC housing has 2 bolts in it. One is a breakoff screw, and the other is a regular flathead. It might be easier to take the AFC housing off, and do it, but this lets the AFC foot come back a lot farther by loosening the allen screw with the locknut on it, and in valet mode, it will cut the fueling back a lot. And if you want more fueling in valet mode, tighten the allen head screw in a little bit until you get the desired fueling. Its an easy adjustment to make once you get the cover off the housing though. Give it a try, and let me know your findings. I bet you can make it run how you want without changing plates as long as your AFC housing is working properly. In valet mode, the way i have mine setup, it will make around 20-25psi, and Max EGT's are about 1k degrees, and the truck still runs decent. Its well worth a try. I will try and find a picture of the adjustment im talking about

On Edit:

Here ya go, found a link with a great picture. Scroll down the the cutaway picture of the pump. The "smoke screw" adjustment is what you will be playing with.

http://www.cumminsforum.com/forum/94...00-pump-2.html

Eric

 

Thanks Eric. I have my head out right now and actually have the AFC housing off. I will try it for sure...

Dave

 

Hey Eric what about the smoke screw. I would love to have a lot less smoke if I can get the 100 plate to work better with my valet switch. How is the smoke screw adjusted for less smoke. And does the smoke screw take away power as well?

Thanks...

Dave

 

an exhuast housing is the Hot side of your turbo. I was wondering if you changed yours or not?

 

The smoke screw can do a few different things, especially with a valet switch.

If you loosen the smoke screw it will:

-Cut the power down in valet mode(the farther out the screw, the less power you will have in valet mode) The AFC spring MUST have some preload on it for this to work though. If the AFC spring is really loose, it wont push the AFC foot back like it should, which is what cuts the power back.

-Cut back the smoke on the bottom end a lot both in valet mode, and in "full fuel". You can probably dial the smoke almost completely out if you play with it enough to get a good happy medium.

-It may effect spoolup, but im doubting it will make a lot of difference either way. If you have the AFC spring very tight, it might make the power not come on near as hard in full fuel(more linear), but if you only have it tight enough to keep a little tension on the AFC diaphram, you shouldnt notice any real difference. It shouldnt make any difference at all in overall power, but bottom end smoke should be cleared up a lot, depending on how much you back the "smoke screw" out.

If you tighten the smoke screw it will:

- Increase bottom end smoke, and may give a little faster spoolup.

- Be harder to control the smoke while driving if you arent very linear with the throttle

- Make the power come on more rapid. It wont be as linear. This also depends on the tightness of the starwheel though.

Hopefully I have helped you out a little with this. You can make a P-pump very driveable if you dont mind spending some time playing with it, and tuning on it. Basically, the Starwheel, and Smoke Screw are what controls your low end fueling. Keep in mind, the tighter you have the starwheel, the more linear the power will come on, and that the starwheel must be tight enough to keep a little pressure on the AFC diaphram in order for it to move the foot back when you back the smoke screw out. It helps a lot that you have the AFC housing off the truck, because you can play with the starwheel, and smoke screw while the AFC housing is on the bench, and see how it moves the AFC foot. Also, remember the plate doesent do anything until you get enough boost to push the AFC foot back out of the way of the governor arm, so the plate really does nothing for a change in Pre Boost fueling.

Let me know if you have any more questions. I'm no expert, but I have played around with a P-Pump enough to get me in trouble

Im also really anxious to hear how loosening the smoke screw works out for you, so be sure and keep us updated.

Eric

 

Eric as soon as I get my head back in I will try the mods we talked about and report back in. Thanks for all the help......

Dave

Happy Holidays people....

 

Update:

Head is back on and truck is running great. Idles really nice. But I am having issues with the 4K kit. Won't rev past 3K and wants to cut out/sputter at 3050K . I installed the 4K with both springs being at .147. Drove truck to find it not revving past 3K. Then I clicked them 2 more times to see if it would rev better. It revs quicker to 3K but not past. I did my valve job my self. Maybe I did not get the valves close enough. Also I am running my #8 Plate in the middle right now. Maybe I am not getting enough fuel in the higher RPMS? Maybe I need my 100 plate back in there?