Club Cobra - Need source for aluminum diff housing for CSX/Kirkham cars...

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- - Need source for aluminum diff housing for CSX/Kirkham cars... (http://www.clubcobra.com/forums/scratch-builders-forum/109860-need-source-aluminum-diff-housing-csx-kirkham-cars.html)

Quote:

Originally Posted by Jerry Clayton (Post 1119585)

Alum weighs 1/3 what steel weighs

true, but to get the strength of steel it has to be ?x the size, so the wt difference is negligible.

when i changed out an iron 8.8 for an aluminum 8.8 and weighed the two i remember thinking, wtf am i doing all this work for a few pounds, and they (#'s) are located low and were for an irs.

Read last posts about weight. Then out to the to check it out. .................

Lincoln aluminum 8.8 #59.0

1960's jag #102.4

Kirkham bare no guts #23.2 Somewhere I was told about 45 pounds difference

between iron and aluminum cobra rear. Mark

cast iron 8.8 w/open gears, no rear cover 70.3#

rear aluminum cover 3.7#

brent you want that cast iron unit it's yours, shipping might be kind of rough...

Are you serious? A 4HU center section weighs 100 lbs?

I never did find any numbers on my jag center . But it weighted 100.2 pounds . See scratch builder thread jag in a 289 chassis. The pics I posted is the one I have. Are you going to build like an original 289 or 427. Mark

Brent, food for thought in your car/application.

I made up an alloy housing that accepts a 9"/31 spline head unit for a car similar to a Cobra, up until this season we have had a trouble free run thru six seasons of racing with this unit...however, this year I made up a new throttle pedal system for the car that was more user friendly for the driver...toooo friendly, he now found that he was able to side step the clutch & simply modulate the wheelspin with throttle from a standing start. This considerably shortened the axle life expectancy...:)
We are now looking to go up to 35 spline unit & axles to combat this..... IF this was a normal 9" with axles say 26"/28" long to give some cushion I dont think we would have the problem, but since the effective axle length on LHS is only about 2.5" there is nowhere to act as such. Car has U-Joint halfshafts which I think contribute to the instantaneous loads at clutch drop, but we are sort of stuck with those for the moment... CV's with a lighter half shaft of reduced dia to act as a torsion absorber would help.