Technical The Allure of the Quick-Change Rear End.

Jive-Bomber submitted a new blog post:

The Allure of the Quick-Change Rear End.

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Yep, had to have one. Converted it to late model 28 spline axles and bearings per some old R&C articles. Having to pay $75 for the center section made it a lot easier.. Been on the road since '87. Yes, it's noisy.

 

Not as strong as the old 9" and no limited slip are pointless arguments up against the cool factor of a quick change rear in an early hot rod

 

When the Salt Circus was built, it had a quick change, but now it has a 9 inch which is better for racing. QC eat 30 to 40 HP, but, I wish it was still with the car as it made it more hot rod then land speed. Why is it gone you might ask? Well it was built in the 80's and George threw in a early ?Culver City Halibrand and the PO kept it for a street hot rod project.

 

Then you have the new Winters nostalgia quickchange that I bought and installed in my RPU.
Wedge lock differential and plenty strong.
And really pretty too.
And yes, I had to have it

 

I have a perfectly good '36 rear with a later 3.78 gear set for my AV8 project. Yet I still covet a new Winters V8 QC. Saving my nickles and dimes.

--louis

 

Nice socks

 

I lucked into a Culver City center with cover a year or so ago. It sat, nose up with no input shaft, for several years out in the weather before I saved it. It was originally set up, I think, for a dirt racer...it had late axle tubes welded into the banjo bells with late splined axles and weird brackets all over. Plans are to try to get it clean, then use the '40 banjo I saved from a basketcase sedan I parted out to assemble a budget quickie for the Tudor!

This article should be a big help when the time comes to get on it!

 

Ive got a couple for B rearends, and a champ size one as well. No V8's, but some day I'll find one I can afford. None are in cars yet, but I've got big plans!

 

You don't want that old roundy round axle Brett.....Ill just take it of your hands this weekend, shoot ill even bring you another rear.. You want an 8 inch or a 9 inch?

 

I am a believer that a hiboy coupe/sedan and roadster all need a Quickchange! They are just right and if your old you can't hear them anyway!

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If we finish the motor mounts this weekend, maybe we can put the article to good use!

Don't forget the pedals!!!

 

There are numerous articles right here on the HAMB about QCs.

As Blue One said, the Winters is as good as it gets for V8 Quickies. (They are better than the original Halibrands,,,,,,,,,BLASPHEMY!!!!!!!!)

If you want to stay traditional, it will cast more money, but they can be built to be reliable and quiet.

I'd like to see the documentation on a 30 -40 HP loss with a QC. The QC ring and pinion was is a bevel type and the 9" a Hypoid, there is less drag on the QC R&P, but the change gears cause some power loss to the rear wheels. About a wash as far as I can tell.
Smokey claimed 10 HP lost through the QC gears.

 

Theory puts it about even with the excessive offset of the 9", but I read on article on the 2nd rank NASCAR late model series in which many cars use the big Champ QC. The article said that cars running the 9" on a fast track had to use a pump and cooler to avoid frying the gear oil, while QC cars were able to run without rear end cooler. That heat is directly lost horsepower caused by the friction in the deeply offset R&P of the 9". Remember, the early Ford R&P in the QC runs on center and so has much less gear friction than the 9.

 

No need to be concerned about horsepower loss if you start with enough.

 

Spit whiskey all over my keyboard!

 

Sounds like you may need to go and make a quick change.

 

Where did you get those adapters for the Champ to 40 bells ? I like the better than the ones I have.

 

Jive Bomber, cool thread, as usual !

 

I used a Rodsville version of the Halibrand V8 with '40 bells and '50 Mercury ends, axles and brakes in my '27 roadster,
'got a couple thousand pain free miles on it so far..
it's one of the parts I just had to have in it.

here is the chassis coming together last summer.

 

I, m using aWinters V8 and old style axles for my Modified ! Chevy 2 4 banger should'nt break keyways I hope

 

Some numbers from Ford engineering, about 1935. Book has a section on power losses between engine and rear tires.
Each extra pair of gears turning (as in transmission in lower gears) costs 8%...(high gear straight through costs only 2%). I'd guess they are talking spiral cut gears, since discussing '30's transmissions, so QC with straight cut gears would likely lose a bit less here. The engineering principle here is of course that making noise costs less power than making friction.
R&P and related bearings, oil, etc. lose around 10%. Again, since early Ford this would likely refer to an on-center spiral cut set. A 9" would lose more here since hypoid, and of course the 9 is about the most extreme offset there is before you get to a worm gear drive. Just a few numbers, so make some guesses, add and multiply, and we will have a reliable guesstimate.
When discussing, say, a 135 MPH flathead street roadster at Bonneville in 1953...how the hell much power could it have lost?

 

Nothing more traditional than a Quick Change and 3 pedals.

 

Quick change noise is ok as long as you have a cam gear drive. Keeps both ends noises..

 

Strait-cut spur gears, on the street, is 50% of the cool. Always has been.

 

I just got to have a QC one of these days. For some reason I think it would cooler under my '55 than my '34.

 

The ribbed adapter plates are C.A.E. They are fairly rare. These may be repopped in the future. The center section in that photo is a Halibrand.

 

Mine now under the roadster project. Running and driving now!

 

It started for me with wanting to use a Muncie close ratio 4 speed but starting off in 1st gear with a 2.20 low gear is an exercise in clutch slipping...soooo, I decided if I use a quick change I can use my 4.61s around town and be able to drive the car around town....then I can swap to my 3.25s for road trips and as a bonus I get to listen to the Q.C. whine.
View attachment 3

 

My Winters Q.C. under the back of my 54 Stude wagon. Has Chevy Truck arms holding it together that you can see if you look. The car is held up by a coupla jacks in this picture.
At normal ride height all you can see is about the lower 1-1/2" or 2" of the gear cover.

Mike