carb stumble???
07-23-2009, 08:50 PM
#14
Senior Member
RACING JUNKIE
Join Date: May 2006
Posts: 2,044
You were definetly too lean with them 66's on the primaries.
When you added that single plane manifold you killed a ton of bottom end torque but gained alot of upper end HP, jetting it up the primaries should help out the stumble.
If it were me and I wasn't runnning a P/V I'd jet it 80 sqaure as a starting point, then after making a full pass I would read the plugs and jet up or down as needed.
let us know how it pans out.
Cp
When you added that single plane manifold you killed a ton of bottom end torque but gained alot of upper end HP, jetting it up the primaries should help out the stumble.
If it were me and I wasn't runnning a P/V I'd jet it 80 sqaure as a starting point, then after making a full pass I would read the plugs and jet up or down as needed.
let us know how it pans out.
Cp
07-24-2009, 05:50 AM
#16
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MASTER BUILDER
Thread Starter
Join Date: Apr 2009
Posts: 175
I drove the car this morning, carb works 100 percent better. the stumble is gone.I am going to test and tune sat. after I make a few passes should I try gradually bringing the primary jets up in size???
07-24-2009, 07:40 AM
#17
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RACING JUNKIE
Join Date: Dec 2007
Location: ohio
Posts: 816
i would baseline the car with a few run, reading the plugs, takeing note of the mph, then go up 2 jet sizes, if mph increases, then you were a little lean, if mph drop, you are a little rich, i like to keep my jets square.
07-25-2009, 01:23 PM
#19
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MASTER BUILDER
Thread Starter
Join Date: Apr 2009
Posts: 175
well I didnt make out real well today I only got 2 passes in and they was enough to make any judgement. the first pass was 13.78 and I missed 4th gear. then I had a leaky fuel cap problem and decided to take the exhaust off and the car ran a 13.77 and I had no shifting issues. :lol: . I went for another pass and stage the car and left the clutch and my driver side axle twisted off. :shock: Has anyone ever used superior axles?? the summit rep highly recomended them to me ... I'm still a little stumped on second pass being almost the same as the first. could it be that my engine likes a little back pressure?? I will post the time slips in order below.LET ME KNOW WHAT YOU THINK . THANKS IN ADVANCE!
RT...247
60'...2.094
330..5.791
1/8...8.807
MPH..82.31
1/4...13.787
MPH..99.03
RT...120
60'...2.058
330..5.805
1/8...8.873
MPH..80.84
1/4....13.771
MPH...101.59
RT...247
60'...2.094
330..5.791
1/8...8.807
MPH..82.31
1/4...13.787
MPH..99.03
RT...120
60'...2.058
330..5.805
1/8...8.873
MPH..80.84
1/4....13.771
MPH...101.59
