Advancing the pump timing a tooth

[mhuppertz]

Anything I need to know before I advance the pump a tooth???

[KTA]

Be shure you dont push the pump key out when you are putting the gear on thats my advice.

[mhuppertz]

Be shure you dont push the pump key out when you are putting the gear on thats my advice.

I will be doing the deed while I have the case cover off for bolt tightening/leak repair. I will shove some shop rags down in there though!!!!

[bgilbert]

If you got the cover off, I suggest rotating the engine to TDC, which will line up the marks on the cam gear and pump gear. The pump gear letter will be E. Rotate it to C. If you try like I did the first time by just pulling the gear anywhere, not placing the engine at TDC, like I do when I pull pumps (keyway at 1 o-clock), the damn pump shaft might be in between cylinders and click/jump/move on ya . Then you gotta mess with everything to get back to where you started. It's much simpler by doing the TDC thing, which the key will be at 6 o-clock, just keep an eye on it, and then pull the gear, back the engine up a tooth, put the gear back on. Clear as mud?

[Fnschlaud4620]

Why is this needed?

Is there not enough advance avaliable with just moving the pump in the oblonged holes?

sorry about all the dumb newbie questions

Fnschlaud4620

[bgilbert]

Why is this needed?

Is there not enough advance avaliable with just moving the pump in the oblonged holes?

sorry about all the dumb newbie questions

Fnschlaud4620

Enough for what? How fast do you want to go? From what I understand, you can only get so much advance within the pump slots. I wish I knew the timing numbers one can get with the pump ALL the way over to the head. IIRC, I counted the number of teeth on the pump gear, divided that number by 360.. or the other way around and came up with ~6*. I want to see someone try advancing the pump gear two teeth, then retarding the pump all the way in it's slots. I would've, but I got lazy and didn't want to fool with it. As of now, I have jumped one tooth, and have about a 1/2" between the pump top and cylinder head.

Sounds good, but might be timed high for some though. I will say I started it up the other day when it was only like 38*, after not being run for a couple weeks, and it banged and rocked the truck back and forth awhile . Kinda like one of them pullin trucks with a bad lope.

[Fnschlaud4620]

So if I am getting you correctly,

more power is avaliable beond what the slots can move the pump.

I was under the impression that you could only bump the timing 1/8 of an inch on the later intercooled trucks.

I was also under the impression that being I have a Non/intercooled, the timing was pretty close to being as far advanced as it could for max power. I see that this is not the case.

I would guess that this is an upgrade for when I get fireringed, or is a stock headgasket able to live?

[KTA]

All of the above is possibly true or possibly not. Max power and engine performance is not acheived by just doing what others do. It is achieved by tuning your particular combination.

[Rebel Ram]

I was being patient to see why this would be done. In my adventures in pump play, I have had my pumps turned in the advanced direction enough to make my engine miss and shake under moderate acceleration. Is the desire to advance a tooth due to the need for more room between the AFC housing and the head? So do tell. BTW I time by ear and performance. Small adjustments till I get that sweet spot. Please dont tell me this is dangerous. Its always worked for me. As soon as I find out its wrong I'll have problems.

[bgilbert]

I was being patient to see why this would be done. In my adventures in pump play, I have had my pumps turned in the advanced direction enough to make my engine miss and shake under moderate acceleration. Is the desire to advance a tooth due to the need for more room between the AFC housing and the head? So do tell. BTW I time by ear and performance. Small adjustments till I get that sweet spot. Please dont tell me this is dangerous. Its always worked for me. As soon as I find out its wrong I'll have problems.

I do the same. By ear and performance, basically how KTA said. Tune it to my likeing. Some on DTR have mentioned it helps for when you want to do gov spring jobs. But I only see doing that job once, 366 in, done. If you were to experiment with difference springs, length, stiffness etc, then I could see this helping.

Maybe mine is different. I don't have any misses or shakes under load or in neutral. The other day I ran it up to 4k rpm no load and it sounded great and never missed.

This may work for some, but it all depends on your use of the truck and what you intend to do with it. I think it's a good idea for most trucks. Since you can always retard the pump way back, it's like just having a little extra available for you down the road when you get crazy or whatever. For example, let's say a good daily driver, fuel mileage, performance timing spec is 17*. This might be at the low end of full retarded in the slots and pump gear advanced one tooth. Now you can start at 17*, then just go up from there within the slots.

[PToombs]

If you got the cover off, I suggest rotating the engine to TDC, which will line up the marks on the cam gear and pump gear. The pump gear letter will be E. Rotate it to C. If you try like I did the first time by just pulling the gear anywhere, not placing the engine at TDC, like I do when I pull pumps (keyway at 1 o-clock), the damn pump shaft might be in between cylinders and click/jump/move on ya . Then you gotta mess with everything to get back to where you started. It's much simpler by doing the TDC thing, which the key will be at 6 o-clock, just keep an eye on it, and then pull the gear, back the engine up a tooth, put the gear back on. Clear as mud?

If you remove the tab on the outside of the pump, near the front, and tighten the bolt down, this will lock the pump to prevent rotation. The tab has a pointed end, fits in a slot on the pump.

[Greenleaf]

I time by ear. Both gas and diesel.

With the gas engine, you have to remember that the oldies are timed for use with a fuel that was very much different than we have today. Seems diesel is changing too, right?

Anyway. I don't think it dangerous.

[Begle1]

I've heard that the 1-tooth advance is a little bit more advance than the 1/8" timing bump, which is recommended stock. POD's or heavier injectors and 1/4" or even more is recommended, which is where the pump starts hitting the head. So the tooth advance is really only called for when you get the smoky injectors.


But doesn't the tooth advance only take about 5 minutes while you're doing a KDP job?

[Rebel Ram]

With the explanation it does make sence. With my modded pump I had the AFC bumping off the head. It was nearly impossible to get to the idle and fuel screws. Another project, Just what I need.
About the danger factor of to much advance. Wouldn't our engines make horific noises and run like crap long before any preignition damage took its toll? On a couple of occasions I inadvertantly left my exhaust brake on and got on the throttle. WOW! Very noisy. Sounded like a 74 merc with 20 year old gas.