Technical The Allure of the Quick-Change Rear End.

Frenchtown,
I can change gears in under 10 minutes and eat a sandwich.

I timed myself once on a QC on my assembly fixture, under 5 minutes!

 

The 10 spline Highland under Speedy Niedhammer's antique class 51 Chevy in the Mohawk Valley Vintage Dirt Modifieds.

 

Not a sandwich I make!

 

@Dave G in Gansevoort , we're going to have to drag you there some day soon, while you still have a few grey hairs remaining...

 

I'll make the sandwich if you come to vegas and change my gears... and BB/Q you a rib eye steak..

 

Hey, don't get him full, I need gears changed..

 

I've always wanted one of those rear ends made from truck parts for the historical oddity factor. No idea what I'd put it in. Probably a good thing I don't, it would just be junk cluttering up the garage. There's at least three different Timken split style rear ends that went into trucks of that period and I'm not quite sure the extent to which the tubes interchange.

 

I always wanted a QC rearwend, Kidney beam wheels, and a 348 in 40 sedan, so thats what Im building. Here's mine, a Halibrand mag 201 IRS. It was in the Stovebolt Special, but at some point had a failure, and was replaced with a Winters center.
Im having it converted to 28 spline 9 inch stuff, 40 bells narrowed to het the 8 inch Kidney beans under the fenders of my 40 sedan.
Its been a bit of a long slog, at one point I thought it might become a wall clock, but with a couple of talented knowledgeable people, who figured out what was wro ng with it and how to fix it, I hopefully have the rear end Ive always wanted.
You can see in one of the pics that it is almost solid mag from under the middle of the centre all the way to the snout, Ive only seen one other like it, Brian Bass was asked to machine a NOS casting to factory specs, and it was the same as this, also mag.

If you can zoom in on the magazine article about the Stovebolt Special, the top left pic has the suspension setup, and the bottom right is the center section.

 

For those that missed it, have a read of @Jethro home built quickchange tech, you won't be sad you read it!

https://www.jalopyjournal.com/forum/threads/homebuilt-quickchange.733594/

 

Drain the oil?

In the 70s and 80s when I was running sprints on dirt I changed gears between heats occasionally. Hell we applied waste oil to the track to help keep the dust down. A little puddle of oil in the pits was perfectly acceptable.

Jack under the push bar to get access to the cover, a chunk of cardboard, hopefully a couple feet square a little to one side so the oil isn't draining on it. A speed handle with a deep broached Craftsman 1/2" deep socket because it would hold several nuts if they didn't want to fall out easily and a big pair of channel lock pliers. A second piece of cardboard to lay on if you had a lot of time, but you lose the opportunity to oil the back and shoulder of your fire suit to match your right foot and ankle that are already oil soaked from the leaky torque tube ball on the back of the in/out box.

Okay, slide under and remove the cover nuts, get as many as will come out of the socket easily onto the cardboard. Now move fast, here comes the oil. Use the back of the big channel locks to tap the cover off... hurry, here comes the oil. Cover goes on the cardboard (not in the mud) bearing side up. While using the big channel locks to pull the hot damn muvvuckin' gears out of the case, start screaming "Where's the new set, WHERE'S THE NEW GEARS?" Oh yeah, already on the cardboard. Use the cleanest rag the next car over had in their truck, or more often pull your hand inside the sleeve of your fire suit and use the cuff to wipe off the oil and dirt from the back of the case. New gears go in, cover goes back on and as many nuts as you can find go back on.

Judge the size of the puddle under the rear end, usually less than a quart (you hurried remember?). "Hey, somebody squeeze a quart of oil in there and let it down. I gotta find my helmet and gloves and see if I've got any tear offs left. What, Bill's girlfriend cleaned my face shield and put on the last 5 tear offs? Man, I love that girl, somebody kiss her for me... I gotta get in the car. "Hey guys, roll me back so a push truck can get me."

5 minutes tops.

 

Frankland and Winters covers came off with just 6 thru bolts. Then the gears were fully exposed. Pair of welding gloves for pulling the geaars off, and of course drop them in the oil drain pan (our tracks didn't like us to just dump the gear oil). Get handed the next set of gears, big first on the bottom, small second. Cover back on, and shoot the gear oil in. Same as Fabber, roughly 5 minutes. It took longer to get the gear oil off the hands. I hate the feeling of gear oil on my hands! Usually got a gas soaked rag from the guys next to us, cuz methanol didn't cut it!

 

These tales remind me of my teams helping a race team, thanks for the memories, I can taste, smell & hear it all happening

 

"Get handed the next set of gears, big first on the bottom, small second. Cover back on, and shoot the gear oil in."

Then when you got out on the track you realized that you put the gears in upside down, and you got to to it all over again.

We had a sign on the tool box that the gears were in, "Big Gear on Top, Dummy!"

 

Thank you, thank you Fabber McGee, that was the funniest thing I've read in a long time - I spit out my morning coffee with laughter.

Dave G in Ganesvoort, You know, as I read through Mr. McGee's description that was the first thing I wondered about - how often were the gears accidentally installed backwards. Whoops - we ended up with 3.17 versus a 5.36!

Gearheads QCE, I feel suitably redressed after our conversation last weekend at the Nostalgia Drags. It may take a leedle bit more wirk to change out a 9" pig.

My QC story:
Back in the '70s when I was a powertrain engineer at FoMoCo we had a Torino sized vehicle modified to do some steady state on track fuel consumption testing. To that end we sent a car out to Roush to get modified with a Winters QC rear end. They notched the gas tank to get it in and sent it back with a beautiful wooden case that filled nearly the entire trunk area. Inside the wooden case was every possible set of change gears made.
When testing was complete I sent the car to our outside salvage concern to get crushed (FoMoCo can't sell cars that have been modified for testing) with the explicit instructions to save us the rear end and the case full of change gears.
Several weeks later I called them and asked "when do we get those parts back?"
Crickets. Nobody knew nuttin'.

 

I never got the gears in wrong, but I doubt a sprint car would even start unless the push truck was going about 75.

 

Random shop of my store-bought Winters banjo style. Works great so far.



-Abone.

 

FTF,
We were racing at Sandusky one night. Put the gear in upside down for the qualifier. Fixed it for the heat race and got black flagged for sandbagging
The car was a 64 Fairlane. Weighed like 3,975 lbs. At the scales the pit steward asked us how big the motor was. We told him 390. He said, "You guys could run 500 inches at that weight!" I think the rule was 8 lbs/cu in.

The next generation was a 69 Mustang that weighed 3416 with ballast (about 2500 empty) with a 427 FE.

 

We ran a modified 4 speed, 1st and 2nd gears gone! Supposed to be the hot setup to lower inertia. Had to be able to take off under its own power. And reverse, just in case you had to back away from an ontrack incident. Unlike you sprintcar guys, we also had weight limits, sort of. 2650, single 4 barrel on gasoline, unlimited displacement, usually guys ran 454s, then 30 over, 1st rebuild, 60 over 2nd rebuild, if the engine didn't dynamically disassemble itself.

Of course I had to be different and run a small block Chevy, under 360, injected, any fuel allowed, methanol, 30 gallons max, with a 2450 weight limit. But Lebanon's scales were off, so...

Anyway, get the gears wrong, and it wasn't gonna move! And not that it matters now, but the 54 usually went across the scales right around the weight limit. Maybe above 10 to 15 pounds, maybe below. Then bolt on some lead. As long as the tech guy always saw the lead, you were good. But...

40 gallon sprint tail tank from Speedway, with the size and part numbers changed to the 30 gallon tank. Shell battery, changed after weigh in to a display battery from the Shell station, empty. Still have it in the basement. Drain the water from the main frame rails after warm-up. Change the tires from old M&H tires with inner liners, to the Hoosiers without any. Car ended up around 2200 race ready.

But every one was playing the game...

 

The hood to weight ratio had to be right!