For those of yall that have the 700r4 and 2.73 gears what rpm do you turn at 70mph in 4th. I turn like 2100rpm. Gear calculators say that I have a 3.23 but I dont.

 

2.77 @ 2000 rpm = 77-78 MPH

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86 T/A 5.0 A4 & 2.77 gear
15.62 @ 86 mph
93 Civic 1.6L
13.5 @ 100 mph

 

With the correct input, the calculations don't lie. Double check all your numbers. Then you have to consider:
torque convertor locking up?
tach a little bit off?
speedo a little bit off?
verify the gear ratio by counting the teeth?(someone could have changed the gears)
tire height can vary from brand to brand(did you use the advertised size of the tire or the actual measured height?)
What size tires do you have?


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350 with stealth intake, holley carb, 470 lift cam. 700r4 with .5 boost valve, vette servo, tci lock-up kit, B&M megashifter. Richmond 3.73 gears, powertrax locker, timkin bearings, synthetic lube. Custom 3 inch single into 2 2.5 pipes. 1 1/2 drop springs, 1 5/16 solid front sway bar, 1 inch rear bar, custom subframe connectors, custom LCA relocation brackets. Kobel ground FX, current red metallic paint. Lots of other stuff...
82camaro

 

I checked the tire size several times 25.5

Torque converter is locking because when I tap the brake rpms jump up 100rpm or so but I guess it could still be sliping some.

I counted the gear teeth two times then my wife counted them 15/41 That is 2.73 right?

I dont think my spedo. is wrong but I cant be sure.

My tach ????? most likley, how do I test it without learning to count really fast

 

That's a fast civic! What did you do to it?

Miles

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88 427 Camaro
12.18 @ 113mph 1.75 60ft
Currently installing 3.73's into my 9 bolt (YES,it is a 9 bolt & YES they are 3.73's, not 3.70. 4.11's to follow soon )
www.koolmeister.com

 

My 91 RS with 16" 245/50R16 Tires and 2.73 gears ran 2100 rpm at 70mph. New 3.42 gears with same tires runs 2700 rpm. According to factory tach anyway.

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91 Camaro RS 5.0L Black Convertible 700R4
** Added so far **
*GM Wonderbar,Alston SFC's,spohn LCA's and Panhard rod
*Turbo City Inj Spacer
*Dual Snorkel Air Filter
*March Performance Pulleys
*GM 3.42 Gears with OEM Zexel POSI
*Edelbrock headers
*3" High Flow Cat
*3" Dynomax Exhaust
*Walbro 255 lph Fuel Pump
***Future 330hp Vortec Crate with LT4 hotcam and 454 TBI

 

75mph approx. 1950rpm. 700r4 and 2.73's

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'92 firebird t-tops
305tbi,670cfm tbi, 2 1/2" Dynomax catback, 9x3 K&N open element

 

2.73s 70@1900
80@2000

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late model 91 rs
fully loaded t-tops, red leather
paint- gm red and yellow blend (light red)
custom painted 16" Camaro rims
305 tbi 14"x3" O.E, computer chip, accel super stock plug wires
Edelbrock 3" cat-back
MTX sub and amp, Bose all around
vic_v8@yahoo.com
street kills: a lot of "family" cars, pickups, New v-6 stang, totally killed '86 SC Camaro.

 

Like 82camaro said, is your stock tach off? They are not very accurate. Mine is off about 300rpms.

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1989 IROC-Z 5.7L
NOS 150HP kit
ProBuilt 700R4, PI Vigilante 2800 stall lockup
Baer Brakes 12" Sport System

 

are you sure you put in tire radius, and not tire diameter? that will throw the calculations way off...



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My 1986 Z28
GM350, T-5, 3.23's, lots of go fast goodies, 4th gen Firebird interior etc...
85 IROC w/ 1364 miles!

You'll always find what you've lost in the last place you look

R.I.P Dale Earnhardt

 

if youre cruising at 75 MPH in D youre tach will actually show you what rearend youve got. 2.73=2,730 RPMs 3.73=3,730 RPMs etc.

 

D isn't 4th its third, right?

 

Yea, "D" is third. I don't get to 2000 RPM until I reach about 83 mph. That's in OD with a 700R4 and 2.73s.