Loxus Eclat V8

[Chillidoggy]

56 minutes ago, Nickp1 said:

Yes I believe it does. I'm looking to use the original Lotus mounting point on the chassis but fabricate my own trailing arm to triangulate it all.

So, pretty much a tubular replacement for the Lotus arm? The original pressed-steel Jag arm (as I recall), was inline, which I thought was strange given the arc it would describe, but then I guess Jag chassis men knew way more than I did. I think the forward Metalastik bushes used to wear quickly, though.

I’m intrigued now, so going to see if I can find some old photos of my old chassis.

[Nickp1]

Yeah tubular or box section with a poly top hat bush either end I reckon. The trailing arm shouldn't have any effect on the suspension arc with the jag stuff, its just there to add strength to the bottom arm through triangulation. 

[Nickp1]

Some steady progress on getting the Jag diff mounted into the chassis this week. I've made a top plate from 3mm steel and managed to bolt the diff into position to check prop alignment etc. I've cut away just enough chassis to get it into position but will need to remove more to allow room for the inboard discs and calipers. Before I do this I intend to strengthen the chassis by welding in 1" box section along the length of the rear section then add several brace pieces to triangulate it all. Once happy with the top I'll flip the chassis to make a frame to tie the original mounting points into the base of the Jag diff. Unfortunately there wasn't really a way to rubber / poly mount the diff so the whole thing will be solidly mounted, as it is in my kit car and many TVRs apparently.

 

[alastair_james_cox]

Hi Nick, 

A new years present for you. MOT's from 1983 to July 2007. Also some photos of the body-off restoration. So you can sleep soundly knowing the chassis is OK.  

They were stuck in a box when I sold the car last year. The engine is now in my Elite. Not an ideal situation but worth keeping tabs just in case I ever get the original one back in or the car goes to someone else. 

PM me your address and I'll get them in the post. 

Best, Al 

[Nickp1]

Wow, that's brilliant 😁 I'll pm you.

[Nickp1]

Bit more progress on mounting the Jag diff. This is a lot more challenging than getting the engine / box to fit 🙄😂

 

[Nickp1]

Last part of the diff mounting process is rebuilding the rear supports. All very tight around the Jag diff and bottom arms, but if it misses it misses 😉

 

[Chillidoggy]

Nice.

Difficult to see from the pics, but have you thought about the caliper access?

[Nickp1]

I don't even know what calipers I'll be using yet tbh 😂

Possibly VAG, it'll work out I'm sure......maybe 😉

[Chillidoggy]

You're not using the inboard Jag calipers, then?

[Nickp1]

Not if I can help it. They used 2 calipers with a seperate hand brake one. Some VAGs (Mk5 Golf) use a very similar sized disc 260 x 12mm. If I can devise a mount to get it on there then it'll be much simpler / lighter / cheaper. But yes they'll stiil be inboard 😀

[Dunc]

Here is a pic of the tubular trailing arms that Spyder used to make for Elite's and Eclats. Might be a helpful reference. (Spyder lost the dimensions years ago and cant make them any more - they are very heavy compared with the lotus box steel ones).

[Nickp1]

For Jag or Lotus rear end?

Lotus I'd guess. The Jag setup works the opposite way to the Lotus. The Jags bottom arm controls wheel alignment and is very substantial. The trailing arm is only there to add support through triangulation.

 

[Dunc]

Lotus Elite/Eclat tubular trailing arms from Spyder engineering. Also known as rocking horse poopie....

[Straker]

Found a Spyder price list from the 90’s the info on Spring rates might be useful when you get to the front suspension 

unfortunately there’s no info on their Diff conversions 

[Nickp1]

Cheers, I've done a few calculations on spring rates and travel for the rear ones but not the fronts as yet. I'm going full coilovers all round and they will be harder/ shorter springs but not by a massive amount.

[Straker]

Spyder also had notes on the rear spring settlings, I don’t think they’ll be of much use as your design is different 

 

[Nickp1]

Sat on its Jag back end / wheels for the first time 😀

Bit more diff cradle fabrication work. Going to weld it all in place once I've blasted the chassis.

[Nickp1]

Tacked the rear part of the 'diff cage' in place before the chassis goes off for blasting at the weekend-

Added some strengthening to chassis. Was going to do it internally but suspect it would stop me from fitting the Jag brakes so did it above. Collecting some XJS brakes off a mate this week too.

 

[Nickp1]

Chassis now blasted and front crossmember opened up to clean up and add some internal strengthening. Few minor repairs required but not too bad at all for a 42yr old chassis.

 

[Elite 4.9]

I looked at putting a Jag rear end in my Elite many years ago. I even shoved one up in place to see just what needed to be done and concluded it was just to difficult a job that I didn't want to do and figured out there must be another rear end that would fit. 
And all your work just shows how difficult it would have been. Yours looks very well done and some great fabrication is evident but certainly a lot of work.

Great job undertaking a much needed improvement IMHO!

The other reason I didn't proceed with the Jag rear end is that it is some 30 lbs heavier as I remember it, but certainly much more robust and would not be over stressed in a much lighter Elite. And of course having the disc brakes is a huge benefit as far as I am concerned and getting rid of problem of rear end grease leaking past the seals onto the rear brake shoes. Mine were totally soaked in only 28,000 miles, making the rear brakes totally ineffective.

Not matter what rear end one wants, to replace the original forklift rear end of the Elite, will take a bunch of clever well designed effort like you have to done here. Great looking and well done Nick !

Actually, it is easier now, to find one, than ever before because of most cars including almost every SUV have independent rear ends. AdvanTEK made by Dana, has many to pick from and these have aluminum housings and are much lighter, smaller in size and computer designed with a limited slip locking rear end. These are much more efficient in transferring power but of course would be quite a bit more expensive than the Jag unit.

https://spicerparts.com/parts/axle/automotive/advantek-axles

 

cheers,

Richard

[Nickp1]

Thanks for the kind words of encouragement Richard, they're much needed mate 😉

Fitting the Jag rear end to any of these Lotus's is not for the faint hearted, as I'm finding out, but I still think it was the best solution for me and my car. The Jag diff/ brakes is roughly the same weight as the Lotus 'half axle'. However the shafts and lower arms etc are beefier on the Jag, but they need to be tbh to take the added power / torque of the V8.

I did consider using a BMW 1 series rear subframe but this would've meant cutting the rear of the Lotus chassis at the end of the tunnel and starting from scratch. Lots of the body would've needed chopping away too, something I wasn't prepared to do, just too many unknowns and variables to consider. At least with the Jag setup it is essentially the same as the Lotus in principle and I should be able to pull it off with little or no body mods.

The problem that I'm finding with modifying one of these Lotus's is that the engine / gearbox / diff can only go in one place due to the limitations of the propshaft tunnel. In a 'normal' car you'd have more leeway for the prop to move up/down or side/side.

[Nickp1]

As much internal strengthening added to the front crossmember as would physically fit, 2 x heavy duty channeling and 1 x 1" box section cos that's what fitted snugly in there. All zinc primered before getting boxed back in. How strong is it? Stronger or weaker than std?  Who knows? But it is what it is 😉

 

[EXCEL V8]

When Spyder used refurbish standard chassis they used to add a strengthening piece under the front cross-member - it was curved - like a section of pipe welded along the entire width of the cross-member.

Great work on the diff etc..  I put an LS1 in my trackday Excel a few years ago - 490hp at the flywheel!  I used a BTR hydratrak diff in that, but you need CV's with it.

Pete

[Nickp1]

Thanks, I am going to strengthen below it too as I need something to fasten a sump guard to. The sump sits lower than I'd like but cant go any higher due to prop position in tunnel and bonnet clearance.