The Lotus Grand Tourers

You're right Peter - I've spends hundreds of hours so far just getting the body in a state to paint. I'm really looking forward to some spannering again! I'm fed up of bodywork now! While I was at Mikes recently I had (amongst other things) the rear uprights vapour blasted so I can now start to assemble the rolling chassis. The uprights came out really well (apart from the witness marks from POs awful treatment!) - really good way to get things properly clean . Worth the money.





Does anyone know what the cast-in boss at the level of the outer drive shaft might have been for? It's not used for anything on either the Elite or Eclat, and it's way before ABS sensors etc..

Pete

Been to the paint shop today (Mike at Lotusbits) to look at the almost-finished paintwork: Brilliant! . Can't imagine it even looked that good when it left the factory. Really pleased with my decision to get it done. Should have it back next week - I'll post up some pics. The first time I drop a spanner on it I'm going to be inconsolable

Pete

Pete Boole wrote:... The first time I drop a spanner on it I'm going to be inconsolable

Pete

I can do that for you if it will make you feel better . Another problem out the way.

Hawaiis0 wrote:

Pete Boole wrote:... The first time I drop a spanner on it I'm going to be inconsolable

Pete

I can do that for you if it will make you feel better . Another problem out the way.

But will you have measured the spanner properly - and often enough?

It could be out of round or tapered or anything - you can't just drop any spanner

Pete

Peter, have you considered protecting the alloy casting, e.g. with clear varnish?
And preferably not polished, to keep original and useable in all weathers.

Dave the cog.

Pete Boole wrote:............................................




Does anyone know what the cast-in boss at the level of the outer drive shaft might have been for? It's not used for anything on either the Elite or Eclat, and it's way before ABS sensors etc..

Pete

I'll have 3 guesses in no particular order:

• • 1 ) The boss might have been an "include-it just-in-case" design feature because they worried about using the driveshaft as the only upper link. The unused boss could be used as a upper link location if the solid driveshaft was redesign to have a modicum of slide at a later date? OR, to stabilise the hub against the very generous bush compliance?
    2) Used as an anti-spin stop when machining the bearing housing? That said, the boss has a cast-in reinforcement web which is a bit OTT just for use as a machining location.
    3) The problem with guess 1) is that the boss is probably on the wrong side for use as a link? Therefore my last guess is that it could be used for suspension set-up...a datum point when setting or checking drive shaft alignment. there is plenty of bush compliance in the suspension links so it's useful the check all is good here. Plus, if adjustable links are used at some point, this boss would help measure set-ups? But this idea doesn't explain the cast-in web...

Otherwise I have no idea!

4 to save money they copied a design from something else...?

amarshall wrote:4 to save money they copied a design from something else...?

Aha! A good guess. These hub types were used more widely in motor sport at the time.. and/or Lotus intended to use them in motorsport.

This one has a sliding driveshaft joint AND a top link location ..but not in the same place as the Elite's redundant boss.

DavidOliver wrote:Peter, have you considered protecting the alloy casting, e.g. with clear varnish?
And preferably not polished, to keep original and useable in all weathers.

Dave the cog.

Best thing to use on vapour blasted parts is acf50. I paint it on them wipe excess off

That looks like great stuff Paul - not come across it before - I'm going to get some ordered. I don't like putting clear lacquer on metal - I know I'm only going to have to get it all off again when it gets chipped and moisture gets under it!

Pete

ACF50 is great stuff - originally developed for aerospace applications I believe.
When Lotus had problems with mild corrosion on the aluminium alloy floors of the original Elise (after they stuck the mats down) they shipped ACF50 to the dealers to sort it.

Pete Boole wrote:That looks like great stuff Paul - not come across it before - I'm going to get some ordered. I don't like putting clear lacquer on metal - I know I'm only going to have to get it all off again when it gets chipped and moisture gets under it!

Pete

I use it on 'll my bike engine cases after vapour blasting. I spray little bit into pot brush it on and wipe off excess. It gets absorbed by the alloy but can be cleaned off

A little progress at last . When I rebuilt the diff last year I was amazed how easy it was to spread the casing to get the crown wheel assembly in. This made me think that it must spread just as easily when you dump the clutch! So I decided that since this car will run a higher torque engine the diff might benefit from some help. I've finally finished my diff-strengthening plate:



The dowel on the left is fixed. The one on the right can move by up to 0.030" to allow both dowels to contact the machined depressions in the diff casing, thus reducing any spreading of the diff casing under acceleration/deceleration. The plate obviously fits between the casing and the rear cover.

I would like to publicly thank Chris (chrisw2811) for his great help in drawing up the CAD file for the internal/external contours and his colleague Richard who cut the plate for me using a water jet cutter (amazing!!). This saved me hours on the milling machine! I then drilled the fixing holes and milled the dowel holes and last week got it plated. Ready to go on. Happy with the result

Pete

Wow!

Very professional!

And a good idea!