TR10 / Standard Axle for Lotus

[winbo]

I am a Lotus Super Seven (Series 2) owner looking for a TR10 rear axle housing/assembly. Mine was replaced with an English Ford unit long ago and I am rounding up the parts to bring my car closer to its original spec. Does anybody have such a beast looking for a new home, or leads on where I might find one?

 

[gsalt57tr3]

Everyone who owns a TR10 tells me that I shouldn't put a spitfire 1500 in it, because the rear end won't take the added horsepower. And yet, there are people who think it would make an ideal replacement for what is essentially a racing sports car.

You can't have mine, although we are probably in the same neighborhood.

But what is it that is attractive about the TR10 rear end? Is it the gear ratio, the width, the high quality Triumph name?

Honestly, I'm just curious.

 

[Twosheds]

This guy might have one lying around that he has no use for:

https://www.britishcarforum.com/bcforum/ubbthreads.php/topics/514957/1

 

[Dale]

I am a Lotus Super Seven (Series 2) owner looking for a TR10 rear axle housing/assembly. Mine was replaced with an English Ford unit long ago and I am rounding up the parts to bring my car closer to its original spec. Does anybody have such a beast looking for a new home, or leads on where I might find one?

It's been a few years since I was there, but a junk yard north of Sierra Vista, AZ on Hwy 90, had a bunch of neat old brit stuff which included a couple TR10s. A lot more traffic on that road since I was there, what with the caverns and all, but maybe someone in the Tucson area would know about the place. Good Luck.

 

[TR3driver]

Everyone who owns a TR10 tells me that I shouldn't put a spitfire 1500 in it, because the rear end won't take the added horsepower.

The weight of the car plays a huge role in how much stress the rear axle sees. Both by direct loading, and because the weight on the tires dictates how much traction they have. Plus the early Sevens had smaller engines anyway, their big advantage was handling and light weight.

But I think it's a matter of originality, rather than being ideal. Wikipedia quotes the Standard axle as being one of the major weak points.
https://en.wikipedia.org/wiki/Lotus_Seven

 

[gsalt57tr3]

This guy might have one lying around that he has no use for:

https://www.britishcarforum.com/bcforum/ubbthreads.php/topics/514957/1

I've talked to him, the car had an MG Midget rear end when he got it.

 

[Andrew Mace]

The weight of the car plays a huge role in how much stress the rear axle sees. Both by direct loading, and because the weight on the tires dictates how much traction they have. Plus the early Sevens had smaller engines anyway, their big advantage was handling and light weight.

But I think it's a matter of originality, rather than being ideal. Wikipedia quotes the Standard axle as being one of the major weak points.
https://en.wikipedia.org/wiki/Lotus_Seven

Randall, I think you (and Wikipedia) are exactly right all around! The engine size in those early 7s was comparable to that of the Standard 10, but likely the engine in the Lotus was tuned -- Holbay head, etc., etc. -- to give maybe half again as much power or more than the 35-40 hp of the Standard's 948. But the Lotus weighed virtually nothing, and it originally ran on the szme 13" wheels and skinny tires as did the Standards. I'd not be surprised if axle failures in Loti increased as wider wheels and radial tires...and even more powerful engines were used on these cars. Fact of the matter is that the Standard and Triumph 10s themselves suffered their fair (or more) share of axle shaft failures! Likely the usual cause there was the much heavier car's weigh overstressing the axles? So it wouldn't surprise me to find out that more than a few 10s ended up being scrapped because their axles were already shot.

As an aside, I've seen an interesting mini-trend in recent years of folks "restoring" these early Lotus 7 models back to a "stock" condition, down not only to the Standard 10 axle but to the original skinny Standard 10 or early Triumph Herald wheels! And I've also met at least a couple of 7 owners who do their very best to keep an extra 10 axle in their garage for a spare. (As I think I've said here before, this is essentially how I ended up purchasing my Standard Pennant: a Lotus 7 owner bought it for the rear axle but realized the rest of the car was far too good to part out or crush!)

 

[winbo]

Thanks to all who have weighed in on this.
Originality is definitely the motivation for me as the weakness of the axle is clearly not an advantage versus the Cortina unit. Some vintage racing organizations are stickier than others on originality and that's a possible future goal for my car. The English Ford axle is also a fair bit wider than the original Triumph unit, and getting away from my mismatched lug bolt patterns would be nice.
Thanks again.

 

[aeronca65t]

As an aside, I've seen an interesting mini-trend in recent years of folks "restoring" these early Lotus 7 models back to a "stock" condition, down not only to the Standard 10 axle but to the original skinny Standard 10 or early Triumph Herald wheels!

Yes. I've seen that too.

On a skinny set of Hoosier TDs, many of these cars are more fun to drive (and the lower cornering forces generated by the skinny tires are easier on the cars too).

The skinny-tire Lotus VI below is great fun to race against. The gal that drives it is great and she really tosses it around. The little 1100 Coventry-Climax can keep up with my 1500 engine pulling out of mid-speed turns. Of course the top end aero on these is awful. This one has Ford axles, the front being a solid axle that's split to create a primitive independent suspension. The early cars like this are a real mix of parts. The gearbox is from a TC.

 

[Andrew Mace]

...Lotus VI...This one has Ford axles, the front being a solid axle that's split to create a primitive independent suspension....

Wow! Are we talking early Sydney Allard-style, where the axle is cut in the middle and then "pinned" back together such that the pivot is the center of the axle?

 

[Roger]

...Lotus VI...This one has Ford axles, the front being a solid axle that's split to create a primitive independent suspension....

Wow! Are we talking early Sydney Allard-style, where the axle is cut in the middle and then "pinned" back together such that the pivot is the center of the axle?

It would be more historically accurate to say early Leslie Ballamy, who developed this type of swing-axle front suspension. He converted Allard as well as many Ford and Austin specials. All Lotus up to the Eleven(S1), my father's Simplicity Itself 750 formula car, and Arthur Mallock's early U2s had Ballamy-style swing axles. (n.b. - remember the Lotus Seven came after the Eleven.)
Normally the axles were split in the middle, Silentbloc bushes welded onto each half-axle which were then pvoted on a bracket bolted to the frame. Track-rods were similarly split and pivoted.