69 gear decision
Thread Starter
Instructor
Joined: Apr 2005
Posts: 122
Likes: 48
From: Lebanon PA
69 gear decision
I really appreciate all the help with my last question. (I am a new member). Another question about my 69 rear. If if switch out the 3:70 to 4:11 will I notice a big difference? My motor was built several years ago and a friend stated I need a lower rear to get more cam performance from my motor. Thanks in advance for the help!
Premium Supporting Vendor
Joined: May 2000
Posts: 4,312
Likes: 70
From: Clearwater FL
Yes you will notice a big difference. If your more of a highway driver, you're probably going to get sick of the gear b/c your RPM's will be going through the roof. If your more of a stop light to stop light kind of guy than you'll love the 4:11's. You will NOT have to change you posi unit either. You just have to get a thick 4:11 gear.
Dan
Dan
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
IMHO 4.11 is a lot of gear. I would stay with the 3.7 particularly with a non-overdrive transmission. Unless all you ever do is drag race and you really don't care about street driving at all. 4.11 is going to be turning a lot of rpms all the time.
Melting Slicks
Joined: Dec 2000
Posts: 2,198
Likes: 2
From: Eastern Connecticut
I had 4.11's in a street rod a while back. Even with tall 275/60 tires, it was a lot of gear. I think I would have been happier and maybe faster with 3.93's (in a ford 9"). With the 4.11's I could do burnouts through all 4 gears, but 1st gear was done in 20 feet 
. Highway cruising was also tedious, but not impossible. The guy who bought it went to many shows a couple of hundred miles away. If you have an automatic, with the converter's torque multiplying, I'd definitely stick with 3.73's or you'd never get traction. Joe
. Highway cruising was also tedious, but not impossible. The guy who bought it went to many shows a couple of hundred miles away. If you have an automatic, with the converter's torque multiplying, I'd definitely stick with 3.73's or you'd never get traction. Joe
Le Mans Master
Joined: May 2000
Posts: 6,493
Likes: 6
From: Bloomington MN
Cruise-In II Veteran
I have 3.70's, and even when I had a very big cam, I thought these gears were pretty steep for street driving. I would be in fourth gear on main drags with a 40 mph speed limit. You will shift a LOT with 4.11's on the street with a decent set of pipes (running at over 3000 RPM will get annoying). I think 3.55's are probably a good compromise set of gears...maybe even 3.36's. Unless you have a HUGE cam, 3.70 gears will not hurt your performance IMO.
