Update!
By Jok Nicholson
10/23/03
ere
are a couple of new tidbits on our latest project
car.
First, I was runner-up two weekends in a row at Cedar Falls (IA)
Raceway in Modified (no delay box) class. Currently the Drag Racing
Online Project Vega is leading the Falls Series Points in Modified and
the Project 4-Link dragster is leading in Top with one more week to go.
Second. Engine builder and DRO Editor, Jeff Burk, and I were discussing that
the car had too much gear and it seemed to be
floating the valves or something before the
end of the
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track.
Well, I finally had a whole day to do some testing
and here is what I found.
1. The 750 Race Demon alcohol carb came with #185 jets in primary and
secondary. It felt rich but until some Saturday testing I had no idea
just how overly rich it was.
2. I took the #185s out and replaced them with #144s. That is a major
change and I knew it might be too much but I planned on an eighth-mile
run to test the idea. The car loved it; it picked up a tenth in 60 feet
and two tenths in the eighth, but the EGT was over 1300 at the eighth
so I coasted through. It ran 6.61 at 102 mph in the eighth.
3. I went up to #152 jets and I think we found the "sweet spot" for the
engine/cam combination. It pulled hard all the way through the quarter
mile and ran a 10.42 at 127.45 mph. Best run ever by almost two tenths!
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4.
The engine pulled strong all the way, I shifted
at 6800 and it never missed a beat and hit 7300
rpm at the finish line.
5. The misfire at about 7000 rpm the weeks
before I think was simply a very overly rich
condition. I don't get to do much testing, but
this time it really solved a lingering problem.
I don't think the factory jetting is that far
off if the car had big port heads and a roller
cam but with out small hydraulic cam and 215cc
runners, the leaner jetting was just what the
"Burkster 383" was looking for.
Thought those "inquiring minds" reading DRO might want an update. I
really think next spring after we degree the cam, play with the timing
and try some carb spacers we might get into the NINES with the little
motor that could.
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