First of all, I've got printouts of all they dyno runs, I just don't
have time to enter all the data by hand. I'll let you all know when
I've got them scanned and on line.
CO is a guage of mixture. Randy (who owns the dyno I used for testing)
reccomends 5-6% CO. I did note that my O2 on both needles stayed
around 2%.
After a nearly trouble free week with the stock cylinder head, I tuned
Jasmine on the dyno this morning. The BCG needle was way too rich at
the top end, running 9.5 - 10% CO (rather than the optimal 5-7.
I replaced it with the BCF needle, which when set to 9% at idle (at
1000rpm) ran at about 6% from about 1800-2700 dropping to about 3%
until 3400, rising to 10% at 4200 dropping to 7% at about 4800 where
it pretty much stayed.
Advaning the timing, we lost a couple of horsepower, before we saw any
indication of predetonation, so I expect that I can run a bit more
boost. This would square with my seeing about 6 more horsepower on the
ported head than I did with the stock head.
Some power values from the final run (hp at the wheels):
35.2 2167
51.4 2826
65.4 3525
78.5 4054
89.3 4545
99.0 5097
100.2 5240
102.9 5526
101.0 5696
97.2 5762
95.1 5810
92.4 5854
85.7 5932
80.0 5949
75.8 5959
It was on this run that the Payen head gasket blew. Again at cylinder
#2, this time it's blowing exhaust out the side, but no water. I
checked the block for flatness (couldn't get a .002" feeler guage).
I'm running new ARP studs and nuts torqued to 55 lb-ft. On
installation, I torqued it up slowly. Drove it that night, retorqued
the head the next morning. Drove the car for about 600 miles, and
retorqued the head again last weekend.
The block was shaved to flat when I rebuilt the motor, the head was
cleaned up when rebuilding it to put on the motor. Could the machining
marks from getting the head milled flat be causing me trouble?
This has got me stumped. Oh, and just a touch frustrated.
Larry
--
I've found something worse than oldies station that play the music I used to
listen to. Oldies stations that play the "new" music I used to complain about.
lrc@red4est.com http://www.red4est.com/lrc
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