questions about high compression 4kq's with NG/NF/Hybrid and CISE

[Derek]

>>>Did you have the head shaved when rebuilt
>>I did not, though the previous owner very likely did.
>This would be good information to have...

I think the guy I got it from still lurks on Audiworld, I may track him down
and ask.

>there is a company that could make you a copper spacer for about $100

I agree that's a bandaid solution.  For that price I can get a whole NF
longblock at the pick-n-pull.

> Yes, definitely monitor the O2 voltage,

I'll rig something up tomorrow before I head off to school.  There's plenty
of fast stretches and hills to test load conditions with.

> Also, are you positive you are using the right timing mark, or setting the
> initial timing properly?  (I know, but I've done it before, double check
it)

After seeing this I went back and re-read a few pages in the old Bentley,
pages I must have been over dozens of times, and realized I have been
setting initial advance wrong for years!  There are two marks on the
flywheel, the 0 mark for TDC, and a bar | 6 degrees before it.  Bentley
calls this | bar "ignition timing mark" which I interpreted to be the mark
you line up with the bellhousing notch while twisting the distributor and
watching the flashes from a timing lamp.  I failed to realize that when my
timing lamp is set for 0 degrees and I use this mark, I am actually setting
6 degrees btdc.  This would mean I have been running those 6 degrees, plus
whatever my timing lamp was set to, for a total advance closer to 14
degrees!  No wonder I was getting knock at anything over 1/3rd throttle.

I've probably made the same mistake on both the 4ktq and the Gti, but with
knock sensing ignitions, they don't mind as much where the distributor is as
long as the hall window is open when the flywheel pin comes around.  I'll
have to check on them too.

With that in mind, the motor is currently set to 6 degrees at idle, which is
a noticable reduction in power from 10~14, but allows me to use wide open
throttle with only faint knock.  I think I'll try a little more fuel and cam
timing adjustments to recover some performance and eliminate the remaining
trace knock.  I'll let you know when I find a happy medium and what it is.

Many thanks to all who replied!

-Derek
4ksq 4ktq Gti 16v











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