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+2 chassis replacement questions

PostPosted: Thu Dec 13, 2018 3:50 pm
by kwhittle
I need to fit a new chassis to my early +2
Who is the best supplier ?
Do they supply galvanised ?
or is powder coating better ?

The car was bought with a spare galvanised chassis that had been fitted; but not used?

In measuring f to r suspension turrets on the diagonal, there is a difference of 10mm

Do I replace with new or have this spare chassis re jigged ??
If the latter, who do you recommend ?
Kevin

Re: +2 chassis replacement questions

PostPosted: Thu Dec 13, 2018 4:10 pm
by JonB
HI Kevin

There's not much choice here:

1. Spyder spaceframe
2. Lotus Replacement (galvanised)

Let's call them "subframes". Anyway, the Spyder model has some advantages over the Lotus one: more rigid and better accessibility for engine / diff removal. On the other hand, it isn't "authentic", although I will not get drawn into the debate on that regarding the DVLA.

FWIW I have a Spyder spaceframe and I am quite happy with it.. although it doesn't appear to have the right amount of castor and the rear suspension isn't toeing correctly. As to camber... :)

Cheers
JonB

PS, No idea how you'd go about rejigging a twisted chassis. It seems unlikely that the Spyder items are any more accurate.. as can be seen from my laser alignment check:

http://images.lotuselan.net/lel/53463/0 ... nment.jpeg

Re: +2 chassis replacement questions

PostPosted: Thu Dec 13, 2018 4:20 pm
by RichC
Are you measuring the diagonal from the subframe bolt holes?... as this is the dimension that matters

Re: +2 chassis replacement questions

PostPosted: Thu Dec 13, 2018 7:09 pm
by pharriso
JonB wrote:HI Kevin

There's not much choice here:

1. Spyder spaceframe
2. Lotus Replacement (galvanised)


LR chassis (sub-frames) are not supplied galvanized, haven't been for a number of years because of the heat distorting the chassis during the galvanizing coating process,

LR chassis are all made by Gartrak through Miles Wilkins, then available through any of the normal suppliers; some of whom will paint or powder coat as an option.

Re: +2 chassis replacement questions

PostPosted: Thu Dec 13, 2018 8:40 pm
by Bigbaldybloke
Looks like you have proof that galvanising really does distort the chassis. I went for a Spyder chassis but it was years ago and they offered a sheet metal chassis as well as the space frame version then. It looks more original but has the updates for strength and accessibility that the space frame version has and can be fitted with Spyder design rear suspension if you ever wanted to. Not sure if you can still get this version.
Lots to think about if you do a full chassis replacement, what do you refurbish, what do you replace like for like and what do you upgrade. Lots to think about during the winter evenings!

Re: +2 chassis replacement questions

PostPosted: Thu Dec 13, 2018 10:30 pm
by Chrispy
I've done a lot of galvanising in the past and had plenty of issues with distortion. I wouldn't be too keen on it.

Re: +2 chassis replacement questions

PostPosted: Fri Dec 14, 2018 3:23 pm
by David1953
I would go with trying to get the galvanised one re jigged.
Galvanising is by far the best treatment for structural life. The only problem is the distortion and if you can get past that you are on a winner.
Try talking to Spider or Gartrak (via Miles Wilkins).

Re: +2 chassis replacement questions

PostPosted: Fri Dec 14, 2018 3:35 pm
by JohnP
Is the TTR Plus 2 subframe ex Gartrac too?
JP

Re: +2 chassis replacement questions

PostPosted: Fri Dec 14, 2018 5:16 pm
by alanr
Bigbaldybloke wrote:Lots to think about if you do a full chassis replacement, what do you refurbish, what do you replace like for like and what do you upgrade. Lots to think about during the winter evenings!


Very good points I think..... Also do you strip and paint the bodyshell whilst it is off the chassis?...How big is your budget and much do you want to spend on the car I guess then becomes a very big question :?:

Re: +2 chassis replacement questions

PostPosted: Fri Dec 14, 2018 5:44 pm
by alan.barker
Hi Kevin,
you are very lucky to have a Lotus galvanised Chassis to fit to your Car, it's the best IMHO :mrgreen:
The ones that are not galvanised are not that accurate either. That's why a lot of owners use adjustable Rear Wishbones :?
Stay with the Lotus galvanised Chassis and you will never regret it.
I always assembly the rolling Chassis first including Engine and Gearbox in place. So when you lower the Body in place you can check for clearance between bonnet and Camcover to shim body height as needed.

Alan

Re: +2 chassis replacement questions

PostPosted: Sat Dec 15, 2018 10:59 am
by kwhittle
Well, thanks to all who have replied.
Seems the best choice is to have the galvanised subframe re jigged

(Sorry for my sloppy use of the english language - the +2 is a grp monocoque that sits upon a folded and welded sheet steel subframe. The subframe takes the suspension and steering loads as well as mounting the power train).

I see that Spyder offer such a service as does PNM Engineering, any feedback ?
Kevin

Re: +2 chassis replacement questions

PostPosted: Sat Dec 15, 2018 11:52 am
by alan.barker
If you look at the post above from Jonb he has a Spyder Chassis and the Tow-In at the back is not to Spec. :shock:
So why do people say a galvanised is no good :?
You could check to see if it is square at Suspension/Wishbone points. Rig up a method to adjust as near as possible then later put adjustable Wishbones like many owners do even with Spyder Chassis :oops: :oops: .
I would suggest you do not paint the Galvanising as the paint will peel off.
On my Sprint with unpainted Galvanised Chassis NO problem since it was fitted in 1982 by Saint Miles :mrgreen:
Alan

Re: +2 chassis replacement questions

PostPosted: Sun Dec 16, 2018 1:50 pm
by grassyknoll
I have restored on to a galvanised lotus chassis a d it was a seamless process.

I have also got a plus 2 on a spyder with spyder wishbone rear suspension and will forever steer clear.. as soon as I can get a folded chassis nd original rear suspension I will change.

The original +2 versus a spyder +2: in my opinion the original is far superior drive.

Re: +2 chassis replacement questions

PostPosted: Sun Dec 16, 2018 2:27 pm
by alan.barker
Well said that man. Original is best :mrgreen: Chunky and his Team knew a few things :mrgreen:
Alan

Re: +2 chassis replacement questions

PostPosted: Sun Dec 16, 2018 2:28 pm
by pharriso
alan.barker wrote:If you look at the post above from Jonb he has a Spyder Chassis and the Tow-In at the back is not to Spec. :shock:
So why do people say a galvanized is no good :? ...
Alan

Because people (like the OP) have observed/measured distortion in their new galvanized Chassis. The problem was so severe that Wilkins/Gartrac no long galvanizes chassis.

Just because Spyder's chassis can be poor does not make a distorted galvanised chassis good.