Rear Axle Swap

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Rear Axle Swap

Postby Peter M » Tue Aug 17, 2004 8:47 am

I thought about this question when reading the engine swap thread.

What DO you do with the rear end?

I understand how you could (farily easily) swap an engine--you need to start with the "right" size, and then fabricate mounts so that everything lines up fairly straight.

But the rear end is another story...

You've got the (narrow) width of the car to consider, so most rear ends would need to be shortened somehow (is there a rear end that would fit without major modification?)

But even if you do narrow the track on the axle, how do you mount it?

Given the 1/4 elliptic springs on a Bugeye, and the lever arm shocks, and the trailing arms, it would seem that you'd have to pretty much fabricate everything for mounting (or change how the rear end is mounted to the car?).

My concern there would be getting the geometry right, so the car would still handle...

Am I reading too much into this, or is a rear axle swap that difficult?

If you throw enough HP up front, then it would seem you'd almost have to do an axle swap as well (and if you want rear discs...)

Anyone have some thoughts? suggestions?

Peter M
Posts: 72
Joined: Mon Jun 21, 2004 1:48 pm

Postby SpridgetBoy » Wed Aug 18, 2004 4:37 pm

When I started autocrossing my MkII about 25 years ago in a little local club in Grand Junction, Colorado; a fellow had a '63 Sprite 1098 with side curtains. He had put a Toyota motor and trany in it and blew out the rearend. He got a TR4 rear and cut all the spring hangers off the axle housings then welded on the hangers from his trashed Sprite rear. He just made the measurements and angles match the Sprite. I think that the TR4 was just slightly wider so he placed a 2X4 inside the rear fenders and jacked them out a smidge and added some flares. He used some rims with the proper offset to fit and slapped wider tires on. That car was a handful to handle with about 140 hp but it would fly in a straight line when you pushed the go-peddle. His wife dubbed it the Awesome Healey and even had a plastic label made that looked like the Sprite circle on the hood but said Awesome Healey. He clear-coated it on. (I have pictures in a box somewhere!!?!! He still has the car in Grand Junction.)

This is a good question for y'all. His was one of the last side-curtain cars. Instead of the metal strips, his has thick cloth covered headers along the top of the doors similar to the piece above the top of the dash. The side curtains took longer bolts to hold them in place and he only had one. I searched through the Scotland Yard wrecking yard bins of parts for him on a visit to Denver years ago, but couldn't find another like his; just the short ones. Did another British car used knurled screws like the Sprite for it's side curtains but with longer shafts??? Someone want to contact Ray on this one?

Later, SpridgetBoy
Posts: 372
Joined: Mon Jul 12, 2004 5:47 pm
Location: Colorado

Re: Rear Axle Swap

Postby begorj » Wed Jan 20, 2010 7:48 pm

as far as the rear disc go i have a 59 mk1 with rear disc i used 91 honda prelude rotors and calipers the calipers have the e brake on then also i made brackets for the adapters and fitted the rotors to the hubs
Pit Crew
Posts: 10
Joined: Mon Jan 18, 2010 9:57 pm

Re: Rear Axle Swap

Postby spritenut » Wed Jan 20, 2010 11:12 pm

Many years ago a friend of mine had a MKII Sprite, 1962, he had a Chevy V8 under the bonnet and a Jeep CJ3 rear axle.
The jeep axle held up to all the power, it was the lack of a real frame in the car that gave out on him in the end.
But I was in the car and he did do wheelies with it. FAST was an understatement. As long as he kept it in a straight line.
Frank Clarici
Toms River, NJ
The BETTER not BIGGER Healeys
Posts: 610
Joined: Mon Jun 14, 2004 9:41 pm
Location: Toms River, NJ

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