OD transmission or Gear Vendors?
Iím running a stout 496 big block with a TH400 transmission and 3:50 gears in a Ford 9 inch rear. Needless to say, my RPMs are unacceptably high on the highway. I limit myself to 50 MPH. AND, itís giving me really bad fuel economy.
Years ago, I broke the transmission. I had it built better and itís lasted. I also wiped the teeth off the pinion gear in the 9 inch. I have almost 600 lbs-ft of torque and I hook really good.
-4L80e transmission, my Fitech LS system will run it. Cons: itís really heavy (110 pounds MORE than a TH400) and has the highest HP loss of all transmissions, can easily be built for 1,000 HP. 5-6 grand built ďrightĒ.
-Gear Vendors overdrive. Cons: Gotta beat the floor up a bit, I think itís 60 to 80 pounds, bad drive line angles. Around $2,700.00.
-4l60e transmission, Only like 10 pounds more than the TH400, about the same HP loss, I see shops saying they can build them to handle 1,000 HP. REALLY?? Around 5 grand.
How may I help you?
1971 Monte Carlo SS454-496ci 600hp
1999 Trans Am-500hp
2003 Iszu Ascender XL Limited V8