TR6 Chassis Restoration

[Dex]

Hello everyone, I just joined a couple of days ago having "guested" on here quite a few times and seen some really useful information from friendly helpful people.

I thought since I'm carrying out a body off restoration I'd lash out my £37.00 in the hope that someone can guide me in the paths of righteousness initially with regards to refurbishing the chassis.

I have a 1971 Californian TR6 and am at the stage when I'm going to take the body off, once this is off I intend to refurbish the chassis, and was wondering what modifications would be advisable to carry out ..I know about re-inforcing the weak points after which I intend to have it powder coated, but I was wondering if it was advisable to fit rear telescopic dampers in place of the lever arm type and if so what type is best?

Indeed what type would be best to fit to the front as well?

Would it be also a good thing to fit a rear anti-roll bar?

Another question I have is that the American cars I've seen seem to ride higher than UK cars and don't seem to sit right, so do I need to do anything to correct this?

At the end of my restoration I want a car that is a joy to drive so any advice that I recieve to that end will be most welcome, oh yes I nearly forgot I've already purchased a polybush set ..the Blue variety.

I think thats about it for now ..no doubt I'll be asking more questions later...Thanks for reading my wafflings.

 

Dex

[jonlar]

Hi Dex, a very warm welcome to the best Forum on the 'net! Get a copy of Roger Williams' books How to Restore and How to Improve TR250, 5 and 6. Definitely go for the proper tele shock absorber 3 point mod., my personal preference is the CTM, but others like the Revington TR conversion. Again personal choice but either Spax or Koni adjustables, start in the midway position 'til you know of you want them harder or softer. Keep a look out on eBay for PI kit, they come up quite regularly, to get best BHP etc. you need the hotter cam. as CPs were fitted with, and the MU to match. CP throttle bodies are a lot better than the CR type, are you converting to RHD? Once chassis is up together, I'd be tempted to get it electro-galvanised, then heavily Waxoyled/Dinitrolled. The later heavier front anti roll bar is better, but unless you're planning track use, I wouldn't fit a rear (the Revington tele conversion allows easy fitting of one).

Edited June 4, 2006 by jonlar

[Dex]

Hi Dex, a very warm welcome to the best Forum on the 'net! Get a copy of Roger Williams' books How to Restore and How to Improve TR250, 5 and 6. Definitely go for the proper tele shock absorber 3 point mod., my personal preference is the CTM, but others like the Revington TR conversion. Again personal choice but either Spax or Koni adjustables, start in the midway position 'til you know of you want them harder or softer. Keep a look out on eBay for PI kit, they come up quite regularly, to get best BHP etc. you need the hotter cam. as CPs were fitted with, and the MU to match. CP throttle bodies are a lot better than the CR type, are you converting to RHD? Once chassis is up together, I'd be tempted to get it electro-galvanised, then heavily Waxoyled/Dinitrolled. The later heavier front anti roll bar is better, but unless you're planning track use, I wouldn't fit a rear (the Revington tele conversion allows easy fitting of one).

 

Thanks for the info Jonlar

I actually have the book you recommended and yes I am converting to right hand drive ..all the holes on the "wrong" side have been welded up and filled plus new ones made on the proper side ..lol

I've actually read on here that Spax are not recommended ..although I don't know why.

Also I've been told to keep the car on carbs but to shave 80thou off the head to increase the compression ratio to get the BHP up a bit as the American version as you no doubt know is only 103BHP.

 

Dex

[Richard Crawley]

I've actually read on here that Spax are not recommended ..although I don't know why.

Hi Dex

I don’t remember seeing that post! Nothing wrong with Spax as far as I’m concerned, I fitted them as part of my total resto 3 years ago & have been very satisfied with them; they also have the benefit of being adjustable on the car. I’m not sure I’ bother with the anti-roll bar unless your going racing, from what I’ve heard it’s a lot of effort for not much gain! I kept to standard rubber bushes for the moment & combined with the shocks, the car feels firm & taught without jarring all your fillings out, I may go Polybush at some stage but fit the wrong ones on a road car & it’ll turn it into a bone shaker; there is lots of archive material on which bushes to go for on the forum. Can’t say I’ve noticed a higher ride height on US cars, this can only be down to spring height but I was not aware of US cars using different springs, a look in the parts book should confirm this but I’m sure someone will know.

 

Re the chassis restoration; make sure you do an alignment check as part of the process, tells you how to do it in the BL manual & it’s a day well spent to confirm the chassis is true. Have it blasted & returned for a second look before despatching for powder coating (I’m not sure I would go that route myself). I did all of the reinforcing & repair work & despatched it for blast cleaning but when it returned (primed in industrial Zink Chromate), I was amazed to find the process had revealed several previously unnoticed stress cracks which I was able to repair before finishing the chassis off.

 

Lastly, make sure you have a good look at the trailing arm outriggers as the reinforcing bolt tubes rot out inside the chassis member & check out the central, cruciform chassis members underneath the Brest plates (where the exhaust passes through). Mine looked fine from the outside but I decided to take the plates off to check & the chassis was totally rotten underneath the plates!

[jemgee]

Hi Dex

 

I have Konis all round but they have to be disconnected to adjust - the Spax are adjustable on the car. Another make is Gaz.

 

Hope to meet at the Red Rose meetings - have a look at the calendar

 

www.redrosetrs.co.uk

[jerrytr5]

... but unless you're planning track use, I wouldn't fit a rear....

 

Couldn't disagree more Jonlar. Highly recommend fitting rear anti-roll bar and thicker front for the road. Don't go too hard on the spring rates or too low and convert to rear telescopics. Personally never rated Spax. Use Koni if you can get them as they are noticeably better.

[Bald Rick]

Hi Dex

 

Allow me to add my welcome.

 

Early USA TR6's have a very mild camshaft. 10/50-50/10 with a 240 degree duration. You may get a little benefit from shaving the head but I think you would need to change the camshaft as well. If the car has the early "narrow port" head you should be able to shave about 100 thou off it. The head number is 516323 I think. Always check the thickness first in case the head has already been shaved. Unfortunately although most of the heads are pretty much interchangeable, the 516323 head has different inlet ports (and manifold) to all the others (including the 2.5 saloon cars). Hope this makes sense . There is a good table that details all the heads on the TR Register "Technicalities" CD.

 

Good luck

 

Tony

[jonlar]

Couldn't disagree more Jonlar. Highly recommend fitting rear anti-roll bar and thicker front for the road. Don't go too hard on the spring rates or too low and convert to rear telescopics. Personally never rated Spax. Use Koni if you can get them as they are noticeably better.

 

Hi Jerry, that's the beauty of the Forum, different people have differing views. It rear A/R bar would still be a fair way down my list!

[Dex]

Thanks to everyone for their advice, the body is coming off in the next few days so fingers crossed that I'm not met with too much Tinworm on the chassis.

One quick question though ...how many bodies will I need to lift the tub off the chassis given that all the loose panels are off?

 

Dex

[jonlar]

Hi Dex, no personal experience to date, but I'm sure someone posted in here back along, that it needs 4 or more to accomplish the lift easily - but the scuttle/A-posts need to be strongly braced across the door gap (the doors are heavy, so need to be removed), to avoid twisting of the tub or bending of the floor and sills, and also plenty of room to sit it down. A 24 pack of Stella should do the inducing!

[Dex]

Hi Dex, no personal experience to date, but I'm sure someone posted in here back along, that it needs 4 or more to accomplish the lift easily - but the scuttle/A-posts need to be strongly braced across the door gap (the doors are heavy, so need to be removed), to avoid twisting of the tub or bending of the floor and sills, and also plenty of room to sit it down. A 24 pack of Stella should do the inducing!

 

Thanks Jonlar ...yes the doors are off and the gap is braced in an X format with 1" angle iron.

You didn't say whether to use the Stella before or after the lift ...lol

 

Dex

[jonlar]

Hi Dex, you ask a few mates round for a chilled beer, before serving make them earn their keep!

[Richard Crawley]

Hi Dex, no personal experience to date, but I'm sure someone posted in here back along, that it needs 4 or more to accomplish the lift easily - but the scuttle/A-posts need to be strongly braced across the door gap (the doors are heavy, so need to be removed), to avoid twisting of the tub or bending of the floor and sills, and also plenty of room to sit it down. A 24 pack of Stella should do the inducing!

Dex

My body lifting crew consisted of me, the wife, my sister & her husband; we lifted the body off, carried it through a removed fence panel, onto a public footpath & back through another removed fence panel 50 meter away & into the back garden where it spent the next 3 years being stripped & rebuilt before being carried back out the same way. Weight was not an issue as long as the body is stripped out, just a bit awkward with the women panicking occasionally!

 

As well as bracing the door openings I made up angle bracing accross the inside of the tub, it acted as a jig & kept everything in place while I removed the rear deck & most of the inner rear wings.

Edited June 6, 2006 by Richard CRawley

[bodman]

Hi dex, wow am about to refurb my tr6s weak and feeble chassis. been avoiding it for a few years bet when the door gaps nip ya arms its time! really replying to say that i fitted spax tellys a couple of years ago. was pretty straightforward and made a huge improvement to the car. good luck with your task hope it goes well.

[Andy Moltu]

I'm quite happy with the rear anti-roll bar as it helps to reduce the understeer that you get with the IRS cars, howver too stiff & you end up with having to uprate the front antiroll bar to reduce the oversteer!

 

As a rule of thumb stiffer anti-roll bars are the territory of track cars which run on smooth tarmac. If the anti-roll bars are too stiff you tend to get a bumpy ride as the suspension is less able to cope with ruts & bumps that only one wheel hits because the anti-roll bar effectively forces the opposite sides to move as one rather than work independently.

 

Again rear telescopics are a positive - I'd opt for the chassis mouted ones rather than the in coil ones. There have been reports of the chassis cracking where the shocker attaches. The chassis mounted ones feed the loading back to the chassis where it was designed to take the loading. With appropriate strengthening the coil over shocker option does offer the better geometry however beefier shocks are needed as the travel is shorter.