S CHASSIS How bad can they be?

[gary lusty]

I am having to sell my 2.9 S, I have had lots of e-mails and phone calls asking about the chassis, having owned several older cars, I am wondering how bad can an MOT'd regularly used Chassis can be? Yes an amount of the plastic covering is gone, but any orange / brown stuff is of the rub it off and clean metal underneath variety. I am thinking of urban myths that 'S' chassis are the Devils Spawn and have some wasting desease or something?

[Roy C]

gary lusty said:

...how bad can an MOT'd regularly used Chassis can be? Yes an amount of the plastic covering is gone, but any orange / brown stuff is of the rub it off and clean metal underneath variety. I am thinking of urban myths that 'S' chassis are the Devils Spawn and have some wasting desease or something?

By now most S1, 2, 3's have probably required some remedial work,depending on how well they have been looked after. TVR's rustproofing was fairly cursory, so you can't expect a 17 year old chassis to be pristine (unless you are Mr Sheen). My own S2 has lead a fairly sheltered life, but has had a replacement n/s outrigger and a repaired o/s trailing arm (the fairly common twin achilles heals of the S). The MOT is no guarantee against chassis rot (outrigger hole on top of the tube, hidden by the body).

[S2 Giles]

Unless you get the body off you can only look after it to 80% quality. It will always deteriorate a bit.

Mine has high mileage and ive had to replace my trailing arms - however it only needed its first chasis clean up a couple of years ago & i just scraped back the muck, sanded, painted & waxoyled, there were no wholes & no nasty rust other than surface.

Its on my mind that 2 years on i should have another go at it, but really its in great condition for 16 years and 100K.

the issue is raised alot because the body is all GRP so has no rust, therefore the only main thing to worry about is the chasis. Thats it really. To be honest most mainstream cars will be in a worse state.

[trackcar]

My V8s is a 1993 one so later in production than most .. it's had both outriggers replaced and the rest of the chassis is decidedly rusty. It really needs a body of renovation to be right, but i'll just keep replacing the tubes one by one. I'm about to put a roll cage in it to introduce some much-needed strength, it's certainly a flimsy chasis these days indicating the inherent strength of the tubes is disapearing. The doors don't close with the roof off for example...

My advice is treat all these older TVRs with an "eyes wide open" approach.

[the gazman]

I firmly believe that the S chassis is one of the better treated chassis from new because I have had my body off and despite little or no protection it wasn't that bad apart from the outriggers.
Conversely I have seen 2 body off jobs on 6/7 year newer Cerbs that needed massive ammounts of replacement metal and I'm convinced that the S was much better protected.

However "eyes wide open approach" sounds good to me on any TVR chassis.

Edited by the gazman on Monday 30th October 12:05

[GreenV8S]

trackcar said:

The doors don't close with the roof off for example...

I wonder how much of that is due to the body sagging rather than the chassis. Surely the chassis would have to be virtually non-existent before the load from the roof panel deflected it significantly?

[the gazman]

GreenV8S said:

trackcar said:

The doors don't close with the roof off for example...

I wonder how much of that is due to the body sagging rather than the chassis. Surely the chassis would have to be virtually non-existent before the load from the roof panel deflected it significantly?

That was the problem with the donor Cerb for the S3erbera, the body had warped to write off proportions.

[trackcar]

I don't know the answer to that peter I'm afraid, but I'm putting lots of things together to get to the chassis flex answer :

If you jack the car in the middle the door gaps goo too wide and the door won close because it's then too high

going stiffer on the springing gives no discernable change in handling indicating to me chassis flex is now the governing factor?

over bumps the whole car creaks and shakes and the door gaps visibly move, don't trap your finger in there!

After replacin the outriggers with the chasis jacked up in the middle the doors closed ok for a few days then went back to how they were.



There could well be lots of body sag, but that doesn't explain the other symptoms I have also. The S has no under chassis closing plates and I think is inherently weak in torsional stiffness when new. Older cars with tubes rotting will get worse very quickly I suspect.

[GreenV8S]

Torsionally I think it is quite soft, and that would account for the changes in door gaps when the chassis twists. I don't know how stiff it is in bending, but I suspect if I found out it would be quite alarming so I'm not going to probe too far.

[thegamekeeper]

Hi Jools, what i suspect you are experiencing is the body flexing not the chassis. I am surprised this is happening since I would have thought you have the body solidly mounted to the chassis on a trackday car rather than using the perished rubber packers. When you replaced the outriggers and bolted the body back down with the door gaps set, all that has now happened is settlement in the rubber causing the door gaps to close. Measure the thickness of the packers with the door gaps set correctly and make solid aluminium spacers so the body is mounted "solid". When you make a full cage the chassis stiffness will increase by a massive ammount. Try to design your fixing points for the cage so that they "trap" the body packers and stiffen the body/chassis structure. The single most improvement in handling in a convertible car is fitting a full cage and even they wear out intime. I have just replaced the old cage in a race MGB which had progressively got worse handling and fitting a new gage tranformed it.I you really want to sharpen things up more fit solid engine mounts and if you want to go further extend the front of the cage to attatch to the engine mounts (illegal in circuit racing ). Hope all is well with you and please accept my apologies if I have insulted you by telling you something you already knew, someone else may benefit sTeVeR

[thegamekeeper]

PS in answer to the original question HORRENDOUS. the potential for disaster in these chassis is massive. Remember they started life as £12995 on the road entry level cars and the initial rust protection reflected in the price ( having said that its not that much better on Sagaris ) Up to 19 years of neglect and abuse in a country buried for 6 months a year in rock salt have not helped, there are some disasters out there

[trackcar]

Hi Steve .. no it's all good information, the thing PH is best at!!

To be honest i suspected the body would contribute very little to teh overall stiffness as the centre section around the sills has no depth to it at all in real terms compared to the depth of the central spine of the chassis proper at that point, but if there's useful gains to be made by having solid spacers between body and chassis i will try it, thanks

a very good day to you

[thegamekeeper]

It wont help the torsional rigidity of the car, just the body flex and danger of losing your fingers in the closing door gaps, although I dont know how you get your fingers in the door gaps the speed you drive at. The cage will on the other hand transform it. sTeVeR

Edited by thegamekeeper on Monday 30th October 14:02

[GreenV8S]

Has anyone had any particular problems with corrosion on the TOP chassis rails? I was advised a couple of years ago that mine were starting to suffer behind the bellhousing, and the tubes under the exhaust manifolds are heavily rusted on both sides (although previously well hidden under some nice shiny heat shield material, not sure if that caused the corrosion by trapping moisture or was just applied too late to stop it).

[trackcar]

Mine are very corroded Peter. I've also just repaired a Chimaera chassis of the same vintage as my S (so the same powder coating?) and it needed both top tubes adjacent the gearbox replacing, both outriggers, one piece in front of the n/s rear wheel, and several traingulation tubes .. not for just usual lightish corrosion but because they were holed right through. How the car didn't fold up on today's rutted roads I'll never know.

[F908 Tim]

I am thinking I have a good one despite 117,000 miles on the clock and Kent roads.
Thanks largely to former owners of course.

I need to go over the back half again this winter but am pretty happy with everything i can see without body off. Get under it with 500w lamp and hammerite on the brush and regularly cant find even one chip to repair. (I don't get out enough do I

When the engine was out painted all I could not normally reach again but have to say it did not actually need doing anywhere. the outriggers are original and are good throughout.
Home made Mud flaps help a lot as does blocking off the front of the outriggers with silicone from body down entirely around the tricky bit that is behind the wheel arch and the mounting plates.Pull it all off anually and check,repaint and waxoil,then fill it all up again with new silicone till next year.

Petrol tank cradle has been replaced and catches a lot of crap on mine, and trailing arms renewed four years back.I do rate the waxoil stuff till you have to get it all off again of course!
How much do they rust from inside is my worry.
Is it worth filling with waxoil then expanding foam for example?

[clarenceboddiger]

The following are a few pics of a chassis I acquired to rebuild,3 pictures show the extent of rot to the outriggers and the 4th shows a serious bodge where a garage were allowed to cut a section out of the chassis to remove the starter motor,the resultant repair leaves a lot to be desired and has allowed water to enter the main rails.To repair it I am having to replace approx 40% of the chassis ie everything below the vertical members,not too bad as at least I have the original to work off ,or at least whats left of it.This was I beleive on a car untill near / at MOT renewal time.

[rower]

[quote=. The doors don't close with the roof off for example...

My advice is treat all these older TVRs with an "eyes wide open" approach.[/quote]




I don't think that is too good, maybe just some of the rubber body mountings have given up, maybe not......

[F908 Tim]

[M@H]

gary lusty said:

I am having to sell my 2.9 S, I have had lots of e-mails and phone calls asking about the chassis, having owned several older cars, I am wondering how bad can an MOT'd regularly used Chassis can be?

In short: Knackered.

I looked at a Chimaerea with a current MOT that you could put all your fingers inside the chassis rails, through the rust holes (yep 3/4" wide by 6" sections were simply rusted away and missing along the full length of the rails). That was the worst I have seen.

Edited by M@H on Tuesday 31st October 13:02