Thread: How strong is a quick change rear end?

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Hi All,

I'm putting the parts together for a Nostalgia front engine dragster.

I've been thinking about what rear end to use and thought I'd try something a bit different. I was looking at shortening down a closed tube Winters quick change rear. The sprint car rear axles have a 10" crown wheel and being an aluminium center the whole thing should be light weight. I would also have the option of being able to quickly and cheaply change rear end ratios when I step up the power or switch from 1/4 mile to 1/8th mile.

It'd look really cool in front of the seat in a FED. The quick change pinions would probably be spinning right under the family jewels though.

Machining up the end bells and shortening the axle tubes would be fairly straight forward with the equipment I've got.

They seem to hold up OK behind 700HP sprint car motors but that's with wheel spin on dirt. How would one hold up with 700HP on slicks at the drag strip?


Cheers

I wouldn't be afraid to run one in a FED, but I'd make a 1/4" steel blow-up shield between me and it, securely fastened to the frame structure.

I was thinking of machining up some aloy mounting brackets that would bolt to each side of the centersection (where the bells bolt on). These would be bolted to brackets welded to chassis cross members under the diff. That would be support for the diff and and anti rotational device all in one.

The axle tubes would be attached to the chassis uprights like a normal diff and then the whole thing would be fixed in 3 places.

I was thinking a steel plate in the base of the seat where it goes over the quick change.

Cheers

Michael

Mike

We ran Franklin QC in our funny car and rear engine top fueler, the main reason being to get the drive line lower--and of course the whole car could be lower

we abandoned the idea and went to 9 inch fords simply because the change gears were unreliable----and they won't be under the jewels--they'll be between your thighs against your buttocks and anything else in that portion of your body.

Jerry
Keeling & Clayton California Charger

Mike

Also the choice of rear end and where the pinion is will effect the driveline angle===you can choose what to use to give your car the engine angle you are looking for---usually nose down a few degrees

Winters can handle a lot of power:

"Winters Performance Products manufactures the best quick change rear ends ever made. Mostly used in circle track racing, quick change rear ends work very well in street applications. In most cases the Championship 10" Quick Change is more rear end than you'll ever need (800+hp). All Winters Quick Change Rears use spiral bevel ring & pinions, the most efficient ring & pinion available. Pinion placement of a spiral bevel ring & pinion uses less power, is more efficient, and runs cooler than hypoid ring & pinions. Hypoid style ring & pinions create more sliding action, increasing heat and power loss."

That said - I'm with Techinspector in that I'd have some type of shielding betwixt the rearend and any of my body parts!

Regards,
Glenn

Even with the lower friction of the ring and pinion you must add in the friction of the change gears. And this is for a nostalge dragster on slicks not a street car

Thanks Guys,

I'm building a Jr Fueler (Well thats the plan). It'll be an injected small block on alcohol initially but I'd like to try running 50% nitro when I step it up.

I figure probably 500 to 600HP initially with about 800HP when I tip the can.

The car should be light weight with all aloy motor and a glide in a 4130 chassis.

I'm not building it to win championships, just to have a bit of fun really. A big part of the fun is in the fabrication work.

What motors were you running in the Funny car and TF car Jerry? When the rear failed did any bits ever escape the housing?


Edit: Oops, just checked your gallery Jerry. Nice!

How cool is that! You can actually see the quick change rear in this picture.



Cheers

Michael

Mike

We ran the early 392 hemi and then the Donovan alum 417 when he got them done.

In the rear engine dragster, we broke a side cover/bell that did leave some debries

we felt that the Franklin QC had the strongest change gear cover/housing and that is why we used them.

we also went to zoomie headers the week after this pic was took to help keep the car on the ground

Thinking about you and your friends down there with the fire situation-----

Jerry

Well after a lot of thought and asking the question on a couple of other forums I decided to play it safe and go with a Ford 9".

I went to the Ballarat Swap Meet today and it must have been fate because I found the perfect 9" housing.

I picked up a stainless steel TEX Racing housing for a good price. This diff is set up with stagger i.e. positive camber on one end and negative on the other. Not a probelm though as I'll set it all up straight when I shorten it. The housing is made for floating axles and I'll be able to re use the ends. I'll cut them off and machine them down so they sleeve back into the axle tubes.



The quality of workmanship on this thing is beautiful. It should look great all polished up. I'll need to cut some of the fittings off and weld up the holes.



I'm impressed with the construction. I don't reckon it'll need any extra bracing.



Cheers

Michael

Mike

I just uploaded to my gallery a pic called stuff 2 that shows the driver area of our front engine dragster--in it you can see how confined it is around the rear end and where your legs go over the housing. The pic shows a Mopar 8 3/4 rear which was common in the 60=70 era. The ford is bigger and more offset than the Chrysler

Fords were popular in funny cars and rear engine dragsters where there wasn't a premium on space

Hope your leg isn't removable like the one pictured!!!

Jerry