VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 31 ring gear rivet

What size are the 1931 ring gear rivets?
Thanks for any help I need one.

What rivets are you referring to? If we are both thinking about the starter ring gear, I am unaware of any rivets.

I am thinking he means rear end ring gear. I have some odd size rivets and may be able to help once we get the dimensions.

Dave

If you're OK with not being 100% correct, you should be fine to substitute grade 8 bolts for the ring gear.

My guess is the rivets are 3/8" diameter, for that size you'll want the shank to be ~.2" longer than the total material thickness (ring gear and carrier). McMaster-Carr would be a good source if you decide to go this route or you could make your own using a pin cut to length or double bucking some cold rolled round stock.

-Tyler

Steve congrats on successfully installing your Larry Jackson ring gear!! Perhaps you can right it up as a good reference to us all. Including the name of the shop that installed the rivets...tblack

Especially the name of the shop that installed the rivets.

Steve, It would be nice to here your thoughts on the drivability of your car with the Larry Jackson gears compared to the stock 4:11 gears.

Thanks Tom:
The shop is in Minnisota Dorman auto repair (https://dorman-auto-repair.business.site/?utm_source=gmb&utm_medium=referral)
I purchased rivets on ebay and I actually have some spare rivets if someone needs them plenty to do at least two rings-they take 10. Dorman HOT riveted my ring to the carrier, also used a 200 ton press to do it .
I also purchased BRG'S from a local supplier I gave them the numbers and they crossed them over to new numbers and they were a perfect fits.
I also purchased BRG'S from the Filling station which are less expensive BTW, they had a couple instock but I didn't want to wait two weeks or more to get the others so I did some local shopping. Let it be known I deal with BRG'S on a daily basis so I have a good kowledge of the bearing market so that being said if you are not in a hurry just use the Filling Station those guy's are great people.
I did a lot of research on the final set up on the gears and it really isn't that hard but you also should have a very good knowledge of mechanic's so that part is left up to the person that wants to do a gearing upgrade. As far as step up one thing that helped me is to spray WHITE paint on the ring gear as to see clearly the marking pattern to get a proper set up that is explained in great detail on the owners / shop manual if you don't have one purchase one that is the best advise I can give anyone!

Happy Motoring all

By the way my 31 5 window coupe runs and drives like a dream, what an awesome upgrade. I HIGHLY recommend to do this, a 3:50 gear is so much better than a 4:10 I can make it through an intersection without having to shift and have someone practically run over me! She cruises 45mph and the RPM's are low which saves on them old babit bearings and the engine doesn't sound like it's going to explode.
The speedometer also stayed in tune with the gearing change which was a relief I was affriad it would be way off it wasn't in fact the difference per GPS is only a couple MPH.
Happy Camper.

Thank You!

That is inspiring news Steve. I have a 3.55/1 gear set to modify a 40 to 54 rear end for installation into my 36 Town Sedan. Wally the person I got it from says it really improved the drivability of his 36 coupe. Art

I am surprised that the speedometer reading is as accurate as the GPS indicates. It must have been way off before the rear axle change. The new gear set gives about an 15% reduction in driveshaft speed for the same ground speed.

I’m almost done with the restoration of a 34’ pickup that I swapped out the rear with a 37’ one. Cut the shaft and torque tube done 6.5”, removed the pinion socket, and moved the spring perches in 1 7/8” on each side. I then installed 51’ 3.55 powerglide gears and welded the pinion socket to the driveshaft. Installed 37’ front backing plates, a 36’ master cylinder and pedal support bracket, then new master and slave cylinders. Haven’t taken it down the road yet but the 37’ huck brakes are great. I do notice more clutch chatter when taking off in my driveway but I believe that’s to be expected some. I’ll know more soon when I get it on the road.