chevyrules85

so i just switched from my turbo 350 to a built 700r4

im not positive of the rear gear ratio, but i was told it was 3.42 gears

my rear tire is a 235/60/r15, and with a tape measure it tiny bit under 26"

when im in od and the converters locked and at about 50mph, im turning 2000 rpm, is that right? it seems high to me, could the gears be 3.73 gears?

im just wanting other peoples setups and what kind of rpm they turn at what speeds, thanks guys

joeblue83

iTrader: (8)

That seems really high. When I am going 60 with my setup I am turning 1900 rpms

chevyrules85

what size tire are you running joe? see thats what makes me think that i have some weird gear, cause im so high in od with with converter locked, but maybe my tach is off too... im gonna get my buddies gps cause it tells you exact speed, and maybe figure something out after i test it like that... anyone else?

customblackbird

iTrader: (15)

700r4, stock 3.27 rear gears. slightly higher stall than stock say 1800-2000. i cant get into overdrive until 55mph but im pullin 2000rpms at 60-65. it was lower like 1800-1900 but true dual exhaust 3" i lost alol low end tq.

urs is a bit high. i would say at least 3.42 but i would have thought 3.73 would be higher say like 2300 at 50mph... theres a formula for calcualtiong RPMs at a cruzing speed on here sumwhere....

80schild

iTrader: (5)

With 3:27 gears mine runs at 1950 RPM @ 60mph, and that's without my TC locking up. If my TC locked up like it's supposed to I'm thinking the RPMs should be around 1750-1800.

joeblue83

iTrader: (8)

My tires are 255 50 16's

chevyrules85

anyone else? im starting to think that my rear gears have to be something more like 4.10

customblackbird

iTrader: (15)

SHlT im starting to think my converter isnt locking up compared to 80'schild... which SUCKS!!! AUGH

Jammin'Trey

I am getting with 2.73s about 900 rpm lugging in OD at 45.

And at 60 its about 1600.

pandin

255 50 16 tire 3.07:1 RG OD .7:1 TCC locked 70 mph 2000 rpm 58 mph 1700 rpm.

19CAMARO85

iTrader: (5)

ummm help me lol... at 55 mph im at just south of 3000 RPMS... Car runs great and no issues really but still. 3.23 rear gears, and P245/50/R16 tires. Someone please help me.

80schild

iTrader: (5)

Have you listened to see if you're changing through all of your gears? It sounds like maybe your 4th gear isn't working.

pandin

If your TC is not working right (no lock up/stuck at full multiply/full stall), but I have never heard of that. I would give somebody a call like Dana at Probuilt and ask them.

The numbers for my 3.07 RG, 255 50 16 tire, is 3000 rpm in 4th @ full stall is 56 mph, normal 4th lockup is 108 mph.

The only other thing would be 3rd and about 1/2 as much slip at 3000 rpm, my mph range is 40 to 75.

So with your lower gear and smaller tire, your mph should be just under my numbers.

Verify the rpm, some dash tachs read high with age.

Tobias05

@55mph w/ a 26" tire and 3.42 gearing i am running about 1850 RPMs.

custom built edge torque converter, painless TCC lockup harness.

19CAMARO85

iTrader: (5)

never thought about that, thanks man.

JPhillis

I would think it is a converter problem, I have 4.10's in my 92 and at 70 mph I am running 2800 rpm and I top end at 90-100mph, not sure I still dont have my speedometer right. I know its about 30mph off when I was following a buddy on the interstate.

19CAMARO85

iTrader: (5)

all my gears are being used. But i dont know. How hard is it to swap out a converter? Because i am not able to do that. I wouldn't know where to start. Would you have to take out the motor? -Matt

Reid Fleming

iTrader: (2)

245/50/16

3.27 axle

75 mph = 2300 RPM
85 mph = 2500 RPM
100 mph = 3000 RPM

Try putting the car in 3rd gear and cruising at 70 mph. The tach should tell you what the axle ratio is. In my case, I rev at 3270 RPM.

customblackbird

iTrader: (15)

mine is about the same as reid fleming... my converter is a few hundred more RPMs stall than stock but im at about 2000 at 60mph. 70mph is about 2300.

u have to drop the trans to swap converters. this isnt a big deal if u take it to a trans shop... they do it fast with a lift.