tfringo

What is a decent rear gear ratio for a 435 hp. Is 411 just too crazy. 370 much better? Thanks

Rcdizy

3.90

tfringo

Why you say 3.90. Does the cam profile make the 3.70 hard to drive at a take off?

SteveG75

What transmission?

I am running a Tom's 12 bolt rear with 3.73 gears behind my BBC. I have a T56 Magnum with 2.66 first and .64 6th OD. 25# flywheel.

If I was running a wide ratio 4 speed, I might want a 3.36 rear to drop highway RPM's and use a heavier (35-40#) flywheel to help starts. Close ratio 4 speed, step up to the 3.70 or 4.11 gears and accept that highway driving is going to be at 3500+ rpm.

Rcdizy

Mine just had that gear when I bought it, and I like it.
700r4 trans with a 500hp small block in front of it.

I don't know how much different a 3.70 would be

tfringo

Mine would be close ratio 4speed. I have never driven a 4.11 or 3.70 so I am trying to imagine. I have heard that 4.11 gets old after a while. 3.70 seems realistic. 4.11 seems more for drag racing set up?

Tiger Joe

I would say if you are undecided between 3.70 and 4.11 3.90 would be a good compromise ,its right in the middle!


I think anything in 3.70 ballpark is the best all around gear ratio.


It would really depend on your use of the car. Do you like 2 lane back road cruising all the time and occasionally blasting down the 1/4 mile? then go 4.11


Do you like to occasionally hop on the highway? go 3.70.


FWIW- my small block has 3.70 and I like them

tfringo

Hmmmmm. Ok. I tend to think 3.70

blue427

I changed from 3.55's to a 4.11 and it was a big mistake,3 grand in the high 50's is no fun and neither is 10mpg(keeping your foot out of it). It does keep me from getting a speeding ticket on the highway though. First gear reminds me of my 1954 XK120 jag,gas,clutch,gas before you're through the intersection.After that it's o.k. although you could start off in 2nd.I'd opt for 3.55's as you've got gobs of power for spirited driving and highway cruising.

tfringo

Thanks! I laughed good at what you said. Shifting up through the gears and not even through the intersection. All that neat sound and going no where trying to keep the foot out of it. Dang. All that head jerking around too. My wife and daughter would get a kick out of that. Like driving my tractor. Put some muds and chains on it and go plow a field somewhere. Ya, I think 3.55 to 3.70 be best. Thanks

dugsgms74

I have 3.70s with my L36/M21 car, just about perfect. Any higher(numerically)would kill the highway cruise speed and any lower would make stop and go traffic a PITA.

tfringo

Thanks!

zrc3john

I went from 3:36 to 3:70 gears on my 73 4 speed worked 350....Not by choice, the gears just broke on my 3:36.......I found a 3:70 complete unit and had it installed...

Plain and simple it's really good on the street, not so great on the highway...You can get away with it on a parkway but at the faster expressway speeds you will be 3,200-3,400 RPM.....It gets old after awhile..You'll want to throw it into a higher gear all the time but just don't have anymore....

For the way I use my car if I had to do it again, I wouldn't go higher than 3:55..I used to do 200 mile cruises in my convertible 73 but with the 3:70 gear I wouldn't even think about it anymore.....

I couldn't even imagine 4:10 gears, I couldn't ..I don't care what ratio tranny or aftermarket cam is installed.....I wouldn't even go more than one exit on the highway....

tfringo

Interesting. Wonder how 3.55 gears would be with a 435 on the take off?

shoretogo

I have a 435 with 4:11 rear driving gently get 8 mpg. If you are turning
3500 rpm your speed is 70 mph. Aggressive driving opens other carbs
And drastically reduces mpg. Enjoy !

tfringo

Cool!

I bet that is a crazy feel. Vibrations coming up through the seat a bit. I am really surprised there are that many 4:11 floating around. Crazy set up. People must of thought it was fun to fill their car up with gas. Or maybe they liked the smell of Ethel??

Thanks!

shoretogo

It was popular. I had a 66, my first Vet small engine. Bought a slightly used 67 435 w/411
Purchased new by Phil Philly pitcher Rick Wise ( it scared him). Although it was super fast - I
Could not put up with it's constant overheating. If you were in mild traffic it would overheat.
Traded for a small engine 69 w/ auto & air. My current 69 435 originated at Yenko, the orig
Owner only kept for 1 year ( got married) I've had for 18 years and love it. Installed an aluminum radiator years ago - it doesn't overheat. It is a thrill to Drive. To put your foot in it
And feel the acceleration is worth the price at the gas pump. It does gobble gas !
PS. I am a 73 yr old that has owned 11 Vets, most at one time 4

tfringo

Excellent, excellent!

diehrd

I would go 3.36 if u drive it a lot and do not have an overdrive transmission . I use 4.11 but have a 4L80e w/lock up . 65mph is around 2400 rpm for me.

tfringo

But, doesn't that seem a little contrary to the characteristic of a 435. Also, it is not going to be driven a lot.