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Old 03-16-2019, 07:25 AM   #2
My other car has wings
lejambcr's Avatar
2006 GTO Owner

Join Date: Oct 2018
Location: Benson, NC
Posts: 313
Premium Member

I have a spreadsheet which does a pretty good job of capturing gear ratio and HP/torque impact on 1/4 mile performance. Assuming all things being equal in terms of 60 foot time etc.... I would expect your ET to drop .2 to .3 seconds, your trap speed to go up about 2MPH and your trap RPM to go up about 700 from what you have now. If the converter is tight at that RPM (about 4-5% slip) and your 3rd gear ratio is 1 to 1 which I believe is correct I calculate your trap RPM to be around 6200.
2006 M6 BOM 39K miles
Kooks Long Tubes, catted mids thru Magnaflow Mufflers
Cam Motion Stage 2 Cam 0.553" lift, 214/220 at 0.050"
XAir OTRCAI, FAST 102 Intake
Monster Level 2 Clutch Package, MGW-P shifter
Carbon Fiber 1 piece DSS Driveshaft
Gforce Anti-Wheel Hop Axles, Gforce Heavy Duty Differential Mount Bracket

409 RWT and 407 RWHP

1/8 mile best: 2.04(60'), 5.61(330'), 8.49(660'), street tires and 2500' density altitude, lifting between gears

Last edited by lejambcr; 03-16-2019 at 07:40 AM.
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