Thanks for the advice Greg, The motor was set up on a dyno but I too think there could be some extra tuning on the carbs idle circuit. I do know how to dial it in as far as the idle screws go but that is it.
As for my ignition curve it seems pretty good from the dyno pulls at 35* total and would have to recheck my initial but i think it is at 12* plus 11* vac adv.
Here is what I am trying to clean up at idle.....my emissions test results....
Here are my readings from past tests With fails in red.....
Date & Time -------HC Driving---CO Driving---NOx Driving---HC Idle------CO Idle
2008-06-21 14:13:35 --- 55 ppm--- 2.54 %--------96 ppm-----249 ppm------1.43 % P
2008-06-21 13:11:45 --- 56 ppm--- 2.66 %-------125 ppm-----228 ppm------4.55 % F
2008-06-21 11:24:59 --- 66 ppm--- 3.88 %--------52 ppm-----311 ppm-------3.18 % F
2008-06-21 10:52:31 --- 88 ppm--- 3.59 %-------116 ppm-----457 ppm------4.00 % F
2008-06-21 10:04:13 --- 70 ppm--- 3.47 %-------105 ppm----2000 ppm------0.87 % F
2006-09-08 14:24:01 --- 94 ppm--- 3.80 %--------70 ppm----2000 ppm-------8.12 % F
Passing results for my car as follows
-----------------------HC Driving--CO Driving----NOx driving----HC Idle------CO Idle
------------------------345.00ppm--- 3.49%------- 3415ppm------ 873ppm----- 4.09%
My motor is a SBC 383 that was at 9.7:1 at the time and is mow a 10.2
:1 compression
Cam specs are Hyd roller with 230* int and 236* exh @ .050 and lift is .510 int and .520 exh all on a 110* lobe separation
Carb is a 750 vac secondary Speed Demon, Headers 2 1/2 dual exhaust
The oldest test is were I am at as I have no idea what was done on the other tests other than tweaking timing enough to heat up a bit and I had to jet down the primaries too. The only thing that has changed since then is the compression as noted and I changed the vac advance to manifold vac from the ported vac port.
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