Gears?

[Sandman0747]

I had a 73 with 302 and c4 tranny. Going to be running 35s. I'm assuming the gears are original ( not that much torque and bad mileage). I was thinking of 4.11. I was wondering what anybody else would suggest. Thanks

 

[needabronco]

I would go to 4.56's if you typically run under 70 MPH.

 

[Broncobowsher]

Clean slate, I would pick 4.27/4.30 with the 302. If going to a 351 then 4.11s

 

[SSDDBRONCO]

Clean slate, I would pick 4.27/4.30 with the 302. If going to a 351 then 4.11s

They have that gear combo? Going to look into that.

Sent from my SPH-D710 using Tapatalk 2

 

[bronconut73]

I had a 73 with 302 and c4 tranny. Going to be running 35s. I'm assuming the gears are original ( not that much torque and bad mileage). I was thinking of 4.11. I was wondering what anybody else would suggest. Thanks

I also have a '73 with a 302 and a C-4. I have upgraded to a 351W with all if the hi-po goodies. Erson cam and springs, Comp Cams push rods, Harland Shop roller rockers and guide plates, Edelbrock Performer manifold, and Duff headers.
These items were not added all at once but rather a few at a time and nothing made as big of a difference as re-gearing to 4.11. It had 3.50 gears previously. I now wish I had gone even lower (4.56). Oh well live and learn.
Moral of this diatribe.........go 4.56 (or even 4.88 if it's not your DD).

 

[Timmy390]

I had a 73 with 302 and c4 tranny. Going to be running 35s. I'm assuming the gears are original ( not that much torque and bad mileage). I was thinking of 4.11. I was wondering what anybody else would suggest. Thanks

Not sure with the C4 but I run 4.11's (4.09's up front) with my 3speed manual and 32's. Hitting about 2900rpm at 65 on the highway. Just changed from 3.50's this summer.

As to the the mileage, well mine didn't improve any (may have even gotten worse). I find myself driving it harder now that it has more pep. I'm getting around 7mpg but I'm running rich and I'm sure that's not helping.

Tim

 

[Sandman0747]

Been talking to a lot of people. Most are saying minimum 4.11 max 4.56. Prob going to try 4.56 and see how it works. I can always use a little extra torque with the 3 speed.

 

[broncnaz]

plus you never know if you decide to upgrade to a OD tranny later on lower gearing now will benefit you more.

 

[garberz]

I went with the 4.56's. C4, 35" KM2's, stock 302. Out on the Fwy, I'm at 2900 rpm, a little over 60 MPH. I'm glad I didn't go with 4.11's, It's fine on the Fwy, around town and cruising it's perfect. 4.88's would be a bit low for long trips on the hwy. On the trail a lower gear would be nice. I don't have much torque or HP with the stock 302, so the 4.56's are a nice fit for me.

 

[skerrybronco]

gears

I as well am debating between the 4:30's or 4:56's, C4 on 35's
I found this link in another thread that may help

http://www.grimmjeeper.com/gears.html

 

[DirtDonk]

...I'm assuming the gears are original ( not that much torque and bad mileage).

First of all, don't assume.
All the suggestions are good and it sounds like you've made a good decision from here.
But make sure you don't already have some other oddball ratio setup before you spend the money.
Yes, I know, most EB's of your vintage with autos came with 3.50's. But 4.11 was a factory option and in the last 40 years they could have been changed again.

Never hurts to count some teeth in the front, or turns of the wheel vs driveshaft in the rear, just to make sure.

Knowledge is power... Good intel saves a lot of headaches.

Paul