Overdrive

[Moparmurf]

Who has an overdrive for a bigblock

 

[cudajunction]

Nobody they never made one that ive ever seen. Got tons of small block n slant sixs set ups though.

 

[68GTX4SPEED]

Gear Vendors.

 

[440SportSatellite]

I guess that depends on exactly what you're looking for. As mentioned, the Gear Vendors overdrive unit is a good choice if you want to keep your 727 auto behind that big block. If you're not quite as much of a purist the GM A41 automatic is supposed to fit without any tunnel cutting, if you're willing to cut up your tunnel a little you can fit a Tremec TKO 5 speed or T56 6 speed. Silver Sport Transmissions offers kits for all of those I believe. www.shiftsst.com They have a rep that posts here under the handle Overdrives. I'm planning to convert my '69 from a 727 console shift to a TKO 600 with one of their kits later this year.

 

[GearAddict]

Passon 5 speed

 

[kiltedrunner]

I bolted in a Gear Vendors Overdrive to my 727 automatic transmission. It works quite well, dropping the RPM's down enough that I can run 4.10:1 gears with my 29" tall tires on the highway at 2400 rpm.

Be sure that you use a good trans cooler if you have a high stall torque converter though.

 

[NJRR]

X2. Passon's 5speed is a direct swap with an A833, no mods. If you have $5k for one and don't mind waiting for it to be built, go for it !!!!!

https://www.passonperformance.com/i...documents/Passon_5-Speed_Flyer_2010-11-18.pdf

Passon 5 speed

 

[Moparmurf]

5k? didn't pay that much for the car lol

 

[67 Mopar]

I have a GV, but I know a few guys have swapped in a 518

 

[5.7 hemi]

Gear Vendors! It will turn your 3 speed auto into a 6 speed and your 4 speed manual into an 8 speed, cant beat it and the price is $2895, way less than other options!

 

[747mopar]

If cutting is out of the question then like said a Gear vendors OD or a Passon but if you don't mind a little hacking then a T56 is the ticket. I have a thread (Viper T56 install) in the motor and driveline section that will show you just how much modification installing a T56 will take. The T56 Magnum sold by Summit and others will be nearly identical to the Viper T56 so it will be a good comparison for you.