8" Ford rear years and changes

I have an 8" Ford of unknown vintage and 3:00 gears. I'd like something in the 3:50 to 4:00 range. What are my chances of finding a pumpkin in the boneyard and what years and models would give me the best shot? Do they all interchange?

 

I can't tell you the year but the 8'' has a 3.42 ratio ring and pinion available.from Summit

 

I think 3.55 is the lowest factory ratio you can find and those are scarce. Pinto or Must II are some donors I have heard. Lower than that and you have to go aftermarket. I know factory had 3.25, 3.00 and 2.80 ratios as well.

 

i got a posi unit from a v8 mavrick grabber. i cant recall the ratio though.

 

If ya' find somthin' that still has a tag on it, this might help:


http://www.fordification.com/tech/rearends_ford02.htm

That's like page 2 of 17....

 

During the '60s, the 8" was used on most 260-302 V8 equipped vehicles, (exceptions were the HiPos/Shelbys) and had available low ratios of 3:55, 3:80, 4:11, and lower, usually found in Mustangs, Fairlanes, etc. (I have a '66 Mustang 8" with a 3:80). Ford never, to my knowledge, used the 8" with any vehicle engines larger than 302, so your best bet is '63 to '68 small V8 Fords for the low factory ratios.

 

I disagree with this: Almost all small Fords with the 8" were in the 2.75-3.00:1 range with a smattering on 3.25 and occasional~3.50.

The HIPO cars and Broncos where one would find steeper gears all had 9" rears.

Remember these were light cars with no overdrive and Ford did not push steep gears or limited slip differentials like GM did. A 66 Mustang factory equipped with an 8" and 3.80:1 gear would be a rare find.

 

Finding the gears ratios you speak of will be tough. It may be best to buy to begin with than spend the time and money looking all over the yards and web. Could even be cheaper to try one of these.
http://www.ebay.com/itm/FORD-8-INCH...Parts_Accessories&hash=item460d45a0e6&vxp=mtr

 

I have a 68 Mustang. With an 8" that I built years ago. It had 2.79 gears and I changed them to 4.11's that I bought from Jegs.

Sent from my DROID device using the TJJ mobile app

 

Ages ago I had an 8" center section with 3.40 gears. i know because I counted the teeth about 3 or 4 times. I may well have been aftermarket gears. I bought the centersection used and that is what came in it.