For those that have done it, are you satisfied with the results? My truck is still apart and is starting to go back together. Did yet another KDP and figured I'd try the 1 tooth timing jump. Will still be awhile before the truck is driving, 5" exhaust is tricky on the old trucks

 

A one tooth jump is the equivalent of 10° advance, which is about an 1/8" bump on the pump. Either way, it makes no difference.

 

i thought 1/2" bump was closer to 10*.

 

What do you mean when you say it makes no difference?

 

So there must be 36 teeth on the pump gear?

 

It's more like 72-75 teeth... I dont know how many exactly.

 

You'll be able to pull the pump back far enough to get back to your old timing setting, so no reason not to do it. I'm happy I jumped mine, it gives me more flexibility in tuning.

 

That's what I figured, if I have it apart I might as well do it. That way I can pull the pump back to the stock setting (away from the head) and go from there.

 

how do you do it? i want to because i only want to get into the case once. will i need a gear puller? this is more than ive done.

 

yep, you need a gear puller.

 

Anyone have the dimensions, layout and teeth numbers on all the timing case gears? I have to do my KDP anyway, so when I finally make it in there I can figure this out once and for all. JBradley500 I've been thinking about this a lot since your post on the DB site, (to the point of waking up in the middle of the night pondering it!) and I don't really have any basis for my measurements, apart from reading it on 1stgen.org. I've been wanting to get dimensions to do a mockup on paper to figure how much distance between the pump and head 10° really is.