13mm pump on the street?

Is your pulling tracks made of sand? 4th low at 4500 rpm thats 49.55 mph WOW that would be something to see

i never said it ran 4,500 rpm,s all the way down the track you would need a big cam for that i just said it will run 5,000 rpm,s i do have alot of wheel speed, anyways i am done with this thread thanks for the information and we have mostly clay tracks come on down to southeastern ohio thats all you got to do, come and see how some good running trucks run, if you guys are gonna nit pick everything i say when our too scared to bring your rig down and hook them up, i was just telling what i have if your jelous build something bigger. talk to ya later and i dont understand the hp level in 03 thing.
 
So anyway, back to 13mm pump on the street.... I was contemplating backing the governor springs out a click to see how it does for taking out the no/low load surging. After some more thought and some reading, I'm considering changing my 4KGSK out for a 5KGSK. It seems like when I do reach 40 pounds of boost and smoking pretty heavy I know I'm still not on top of the twins totally due to too much fuel, which I will try and dial back, but I'm also around 2300 RPMs and 85 MPH (estimated, I do have to watch the road). Seems like by the time I do get the turbos spooled all the way I may be way up in the RPM's. Is the 4K enough, or should I go 5K? Or would I get even worse driveability going to 5K?
 
At what boost pressure does your afc arm clear the fuel plate? How far is your pre-boost screw turned in?
 
I haven't taken the AFC off and put shop air to it yet. I was going to check out the smoke screw first. Even with no boost signal to the AFC the fuel comes on hard way before the turbos get a chance to start spooling, the power drops off, and the road behind me goes black. I'm just wondering if backing out the smoke screw would lighten the fuel up, or would backing off the plate be a better idea? Thanks for reading. I appreciate it.
 
Do things one at a time. Back off your pre-boost untill it looses tension, then tighten it till you just feel resistance and tighten the nut. Drive it and see if it's cleaner on the bottom. If not, move your afc housing to the rear and try it again. Try to make it run clean and lethargic on the bottom, then work it up from there.(clean and lethargic may not be possible with a 13mm pump, I've never had one) If it works, try sliding the afc forward untill you start getting your bottom end response back.
 
I have the AFC slid all the way back right now. The way it behaves on the low end really isn't that bad. It's when I get up over 2k RPM that things start to go to crap. But what stymies me is if there was no boost signal going to the AFC (it wasn't hooked up at first) the AFC foot doesn't move out of the way. As RPM rises, does the governor arm eventually rise over the top of the AFC foot and then go forward and hit the plate? Maybe that's at 2k RPM where the fuel dumps on the engine and puts out the fire. Of course, that would make me think when the RPM drops back down the arm would get hung on the top of the foot. I guess I need to pull the AFC off and hit it with the air, see how much boost it takes to make the foot move...
 
Unless your afc foot has been modified, the governor lever does not ride over it. Do you have boost going to it now? What size twins are you running?
 
I have a PacBrake valet switch connected to it now, but it isn't hooked up electrically. I assume it defaults to full fuel. My twins are PS62 over a K31. II towing twins. They are coming off tomorrow and I have a 64/13ss over S480 set on the way (I hope).
 
:mad:It is a real shame that an informative and professional conversation has to be hijacked by some one who is apparently far superior to the users of comp-D. Many of which are nationally respected diesel enthusiasts whose actions speak louder than their words.
 
Yeah, at my level of experience and knowledge, I listen a lot and don't speak much, unless I have a question. Thankfully, the ones that know are kind enough to provide helpful answers. :bow:
 
Okay, I got the AFC off and hit it with shop air. 25 PSI will just get it to budge. 30 PSI gets it to move readily. What boost should get it to move? Also, the plate is full forward! :eek: And when I first started the starwheel was full forward. So the pump was set on kill, pretty much, and I'm running .093 lines and huge injectors. I wonder why I was putting the fire out?? I'm gonna move the plate halfway back and go for a run. Now that I know how much boost it takes to move the plate I can adjust it tighter or looser, based on advice I get here.
 
Did you back off your pre-boost? I set my spring so the afc starts to move at about 5psi. You might try backing off on the starwheel and get the boost to start moving the arm forward at 7-10psi. Be careful tightening up the spring too much. If it coil binds before the afc moves forward enough to clear the plate, you will loose full fueling.
 
No, I didn't back that off any more yet. I did back the plate up from full forward to centered. I did back the star wheel up a few days ago from where I could barely see it in the forward end of the hole by 5/16 roughly so it's all visible but still forward of center in the hole. Would it be smarter to back up the AFC foot preload (smoke screw) than to crank up the tension on the spring by the starwheel? As I loosen the starwheel and release tension on the spring it takes less boost to move the foot, if I understand correctly. Backing up the preload has no effect on the spring tension, but moves the foot closer to the back of the engine (and governor arm)?
 
I would back the pre-boost off till you don't feel any tension. Then turn it in til you feel it hit the end of the rod and tighten the jam nut. Back off the star wheel till it just starts to move with about 7-10 psi of air pressure. Push the fuel plate full forward and then pry it back about 1/32 of an inch, tighten. Then put the afc back on the pump and put it as far rearward as it will go. Adjust your right side mirror so you can see your exhaust. Take it for a drive and watch the smoke. This is your minimum smoke level(at slight throttle). Try your afc full forward and see if there is any difference(should be).
 
okay, I have it set like you said. I'll give it a try and report the results. Thanks for taking the time to provide the suggestions, regardless. :Cheer:
 
Well, just got back from the test ride. Smoke is almost non existent down low, which is good. As I roll into it I get smoke, but it's nowhere near as thick and black as it was. Now it still puts out a pretty good cloud, but the smoke is more opaque, more brownish in color. Boost, sadly, is still not much over 40 PSI. I didn't run the plate full forward. I left it so the washers under the screws cover the slotted holes. If I push the plate all the way forward, I'm pretty sure I'd just put the fire out again. I'm beginning to suspect the way the engine was built with the fly cut pistons, .020 thicker head gasket, big cam that's degreed in, ported head and ZZFab intake, maybe the twins I have now are putting out all the air they can where their waste gates are set (don't ask, I don't know). Either that, or the governor is limiting my RPM's. I didn't get a chance to look down at the tach, but I had it to the boards, and it wasn't gonna turn any higher. I already have the bigger twins with the S480 and race cover on the bottom. Maybe between that and a 5KGSK I can get more out of it. And feel fine shoving the plate forward again. Thanks to Ron A and everyone else for the input. It helped, and educated me. I wanna get all my power from just fuel. I don't want to be a ***** and hafta hook up my spray bars to a bottle. :nos: :hehe:
 
Hook the afc up to an unregulated air source that you know is coming straight from your manifold, or turbo. Be carefull, with boost going to your afc it may fuel so hard that you will need a compass to find your way back home.
 
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