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Blue68 · 05-31-2002, 03:45 PM

http://www.700r4.com/SpeedOCalc/?calc=1 is where the calculator is. You should be turning about 2500 rpm at 75mph in 4th and about 3500 in 3rd (1:1). Put it up on the hoist again and touch your brake and see if it drops. You may be getting lockup in 3rd but never attaining 4th gear. It will sound/feel similar. Since it sounds like your wiring is correct, touching your brakes will result in an increase in rpms, even in 3rd.

I still think you are not getting to 4th gear. As for ruining your tranny without locking up... it is possible due to heat buildup. But since I don't think you are getting to 4th anyway, you will be as okay as anyone running a th350 with 1:1 ratio.

05-31-2002, 03:45 PM	#11
Blue68 Registered User Join Date: Apr 2000 Location: Frisco, Tx, USA Posts: 606	http://www.700r4.com/SpeedOCalc/?calc=1 is where the calculator is. You should be turning about 2500 rpm at 75mph in 4th and about 3500 in 3rd (1:1). Put it up on the hoist again and touch your brake and see if it drops. You may be getting lockup in 3rd but never attaining 4th gear. It will sound/feel similar. Since it sounds like your wiring is correct, touching your brakes will result in an increase in rpms, even in 3rd. I still think you are not getting to 4th gear. As for ruining your tranny without locking up... it is possible due to heat buildup. But since I don't think you are getting to 4th anyway, you will be as okay as anyone running a th350 with 1:1 ratio. __________________ http://home.comcast.net/~r.landrum/w...tos.html-.html '68 C-10 LWB, '98 Z-71 350 w/accessories (Serpentine), Edelbrock Performer, Edelbrock 1405 (600cfm) carb, GM HEI, CompCam Extreme 4x4 roller cam, Thorley Headers, Carter Electric Fuel Pump, Vintage Air, 700r4, 3.73, disc brakes and power steering upgrades.