my buddy has a 91 mustang with a 347,parker tunnel port intake,600 plus soild cam.12.1 compression,c-4 trans.they said the combo should make 521hp.@7100rpms.i would like too know what gears you think he should run.
is the track by you a 1/8th mile or 1/4? like i gard said... there is a lot of diff. factors... tire size, cam, converter, n/a or power adder car, MORE INFO SON! lol
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91 gt,327 stroker 10.8-1 compression , sportsman block std. bore,scat forged crank and rods, JE pistons, trick flow track heat fully raced preped heads, custom n2o cam, victor 5.0 upper and lower, 75mm tb, 36lbs injectors, 2 stage hit of spray, PA c-4 tranz w/ break, 3600 9 inch stall, 8.8, c clip elem. 3.73, spool, 2 way adj. uppers, south sides lower, eibach drag springs and lakewood 90/10 - 50/50, converted all to 5 lug, on 26 inch drag radials!...100% street car!
I was wondering this for mine too. Im not even sure what the differences are though, i just know the lower ratios like mine go through the gears faster. Why wouldnt high be street freindly?
We need the tire height to calculate. If your setting it up for the 1/4, you want to cross the line in your highest gear (3rd) at a couple hundred rpm shy of your redline/shiftpoint. Sounds like 4:30s+, is 3rd gear in the C4 1:1?
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DHG #01434 Bullitt - full JLT intake, MGW shifter, Accel coils (I wish I had 4.10s, o/r H, tune)
Black 89 LX(the drag car) best 8.75 at 80 mph in the 1/8
97 Mountaineer V8 AWD
ok it a 91 gt. weigth i don't know.so tell me if he runs a 26 in. tall tire what will it be or a 28 in. tall tire what do you think.but the car is bone stock 1991 mustang gt.-body-all steel,and he's running a 4000 stall covert.c-4 tranny.and he's building the car for 1/4 track.
If it's a race only setup, then he needs to be 4.56 to 4.88 with the 28" tire. But it really depends on the rpm range the car will be run at. 521hp might be a little optimistic depending on what heads he's using.
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07 GT premium in Grabber Orange. 5spd. manual w/IUP, plenum cover,3.55's, Roush scoop, 14" antenna, C&L CAI, Bamachips 93 Predator tune, Steeda U/D pulleys, Hurst shifter, FRPP GTA's, CDC chin spoiler, CHE LCA, BMR panhard bar, Eibach Pro Kit. FRPP 17" black bullitts and 255R45 Firestones, Spydershaft aluminum driveshaft, MSD coils, D-Specs, Prothane motor mounts, BMR LCA brace, Steeda panhard brace, BMR adj. UCA, Webelectric sequentials, Mikronited FRPP 4.10's.
i have 4.10s with a c-4 and 4000 stall. it has 28" tall and i cross the line at 6000 i am shifting at 6500.i would like to know a formula to figure it out also. all the formulas i have seen want to know what rpm you are at going 60 mph and crap like that.i dont even have a speedometer, my slip tells me how fast i am going
MPH= RPM x dia. divided by 336 divided by gear.
RPM= MPH x gear x 336 divided by dia.
Let's say you want to know how many rpm's you will turn with a gear change. Your trap speed is 120 mph, and you have a 4.56 gear with a 32" tire. 120 x 4.56x 336 = 183859.2 div. by 32 = 5745.6 rpm. Now put in a 4.88 gear, and you will turn 6148.8 rpm at 120 mph.
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07 GT premium in Grabber Orange. 5spd. manual w/IUP, plenum cover,3.55's, Roush scoop, 14" antenna, C&L CAI, Bamachips 93 Predator tune, Steeda U/D pulleys, Hurst shifter, FRPP GTA's, CDC chin spoiler, CHE LCA, BMR panhard bar, Eibach Pro Kit. FRPP 17" black bullitts and 255R45 Firestones, Spydershaft aluminum driveshaft, MSD coils, D-Specs, Prothane motor mounts, BMR LCA brace, Steeda panhard brace, BMR adj. UCA, Webelectric sequentials, Mikronited FRPP 4.10's.
what gear to use 1991 Mustang GT 
