Estimate how fast I was going.

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BanginStang97GT said:
I was in 5th gear at around 5,800 rpms. I have 3.73's. My speedo was pegged but I have no idea how accurate it is at that speed. Thanks, Kev-

Hmm. Well, from first principles:

T45, 5th gear = 0.67:1 (I think)
Driveshaft RPM = 5800 / 0.67 = 8656.7RPM
Axle RPM = 8656.7/3.73 = 2320.8RPM
Assume wheel diameter of about 26" (2.17'); C=6.807

MPH = 2320.8(r/min) * 6.807(ft/r) * 1/5280(mile/ft) * 60(min/hr)

MPH = 179.5MPH.

:rolleyes: Something isn't right. Either I've got the wrong gear ratio for 5th, the tire size is wrong, my calcs are wrong or your tach is wildly off. I don't think a car that manages 94MPH in the 1/4-mile has a 180MPH top-speed.
 
1/2 of 5800 rpms is 2900rpm. Check how fast you are going at 2900rpms,then double it[if your 70mph at 2900rpm, then at 58000rpm you would be going 140] Should give you a good idea.
My 98' with 3.27 gears will do 132mph, using a GPS [same reading as speedo]
 
krly79 said:
177 mph is your ideal mph without factoring in wind resistance. I would say somewhere around 160ish probably, give or take 5mph. :shrug:

Ummm, sorry but no. Stock 99+'s won't exceed 145. Those Mods on a 97 wouldn't get it that fast, then you have add the shorter gears...

I'd say 130 would be a best case scenario, but that's just a shot in the dark.
 
Somehow I just don't believe that a car with your mods would pull to 5800RPM in overdrive.

Even with the power a stock LS1 has compared to an NPI boat anchor, my '99 and '01 Formulas had to make top speed runs in 5th because they couldn't pull in 6th gear.
 
nickthegenius said:
Somehow I just don't believe that a car with your mods would pull to 5800RPM in overdrive.

Even with the power a stock LS1 has compared to an NPI boat anchor, my '99 and '01 Formulas had to make top speed runs in 5th because they couldn't pull in 6th gear.

but your 6th gear is like .05
 
My mod list is vague my biggest of the mods a vortech s-trim, steeda boost pipe, snow performance meth. inj kit and im hittin around 10lbs of boost. I just haven't felt like updating my sig. I have pics if anyone has there doubts. So with that being said what's my est. speed?