Has anyone out there ever put a 5 speed in a 390 FE powered 68 Mustang? Is it even possible? I would like to go with a deeper rear end gear without sacrificeing highway drivability. Any info is appreciated. Thanks, John
5 Speed behind the 390 would be cool, but, go for the TZ T-5. You need the heavier 5 speed, as the standard t-5 won't hold up to the torque of a big block....The t-5's love the rear gear about 3.50 of so....The overdrive makes great cruzin' with the tall gears....go for it....
If I was doing it, I'd spend LESS cash and get a gear vendor's overdrive..they claim an IMMENSE torque capacity, and it doesn't cost any more than a tremec (and you still have to deal with the clutch and linkages!!
Richmond makes a Street Five Speed that claims the first four gear ratios are low for improved acceleration and fifth is a 1:1 ratio. I believe they suggest a gear ratio of 3.00 to 3.50 so your cruise RPM is reasonable. It cost around $1900.00. I'm not sure if it bolts directly in or needs an adapter kit like the T-5.