Hi Guys and thanks for your input.
With the IP set at 1.0 the engine pulled harder at higher RPM's,but had poor power at lower RPM's
With IP set at .90 it has good low RPM power and will even pull good from an idle (in 3rd and 4th gears) with much less downshifting. But some High RPM power was sacrificed.
As far as the "pinging" sound:
First : I Have never heard a diesel Ping before. I always thought the clacking was basically preignition and normal.
But believe it or not- this engine was definately making a pinging sound ,while cruising on the highway. It sounded exactly like a gas engine,with harsh pinging from preignition.
An entirely different sound,from the usuall clacking.
If I accelerated hard,or took my foot off the Go pedal,the pinging would go away and returned while at cruise.
I know this sounds weird. I had a nice size rust hole,in the passenger side kick panel (sence repaired) so I could hear the engine nicely
I used to "flip" (buy and sell) diesel rabbits 20 years ago. I advanced IP in the range of 1.0 to 1.10 on dozens of them. This back in the days before the internet
Therefore I have never done a gov mod or advance mod before this vehicle. While I must say,the gov mod is awsome--adding really impresive and much needed power and nicely increasing the RPM range.
I'm wondering if advancing IP to 1.0 AND doing the "advance mod" as well,might have advanced IP timing too far-resulting in the "pinging" and poor low RPM power.
Agian: the pinging is gone,with pump set at .90
I do still have some light "Bucking" under light and moderate acceleration, between 1500-2500RPM (approx) (NO Tach)
It's just a mild annoyance. I suppose I can't really complain- This truck pulls harder and is MUCH more drivable,than any Rabbit I ever owned (Including a 1.8 - 8V carb'd rabbit I used to own. I can keep up with traffic on the highway (easily doing 65MPH) and Not hold up traffic,when the light changes to Green. Much better than the Rabbits used to be. If I could eliminate the light bucking, I would be totally satisfied. Agian,thanks to all,for your input and I thank you all for this website. I wish It was available 20 years ago,when I worked on so many of these vehicles. Definately an awsome resource !
Thanks,Mike