Thanks Sum. A little confusing about which housing they fit. I presume the 8.5, 9 and 9 3/8 all fit the "9" housing and are basically called 9"? I know the 9" and 9 3/8 fit. Guess I never heard of 8.5 and some of the other RG diameters. I know my 65, 69 and 69 1/2 Boss Mustangs all had what I would call a 9".
Ron
They fit the 8.8 but you have to work over the pinion to get it to the proper depth for the ring gear. I got a set of the gears but we haven't done the works but Ted has. Here is a review of posts earlier in the thread some time back...
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Hi All, We run a 8.8 in our RMR with the 8.5 gears. They do fit but not out of the box. I use the 2.47 ratio but had a problem setting them up. I ended up with no pinion shims and it still needed to move out. I set it up in the lathe and ground for a little more shim room. Worked great. You also need to play with the yoke as the 8.5 spline is different. I got the 8.5 yoke which uses the 1310 ujoint and it was fine. The car has made about 20 trips in the 240-250 range with no problems.
We used the pickup 8.8 housing as it has the heavier 3" tubes. We put 9" bearing ends on it with new 31 spline axles and a mini spool. I've used this set up in the Street Roadster and will be running it in the RMR this year trying for 300 with a turbo engine. The 2.26 gears are out there and are cheap. IWE rear ends only in BC have them in stock.
Cheers …. Ted Allan
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Great, and thanks for posting that. One question, just to make sure.....you used the carrier out of the 8.8 and the 8.5 ring gear fits on it?
Are you going to change to the taller gears for the 300 attempt? If so could you take some pictures of the change to the rear-end and post them?
Thanks and good luck on the 300 mph run, ….Sumner
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Sum, I used the 8.8 carrier and yes the ring gear fits right on. For our 300 attempt we're going to run the 2.47 gears with the 28" Goodyears we are running now. We couldn't get to the final drive we wanted so I talked to Mike Strausberg at B&J, they now make a overdrive unit for their Big Boy trans. We will be using a 1.50/direct single section with the od. It gives us 4 gears, 1.50, 1.20, 1.00, and .80. What's slick is they have lots of gear ratios for the trans and muliple ratios for the od, they are both air shifted which makes it nice for us guys that have the trans behind us.
ted
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Sum, I also am a little confused as the 8.8 has a 2.47 that came in 83-86 F-100;F-150 and Bronco. I have one sitting on the shelf. Maybe that's all he could find. Bob
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Sorry Bob, I should have read the rest of the post. As far as I could find, the highest ratio available for the 8.8 was 2.73. I did have a set of the 2.26 but they were too high for us with the 28" tire so we went for the 2.47 with the set up we were running in B/GRMR with a BBC. With the new turbo set up and a little lower rpm, we found that being able to keep the wheels/tires and gear combo we already had and spend the extra money for a bulletproof trans was a better way to go.
ted
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Hope that helps,
Sumner
