'A' Frame suspension

[ian8542]

Does anybody have any pictures/diagrams of the 'A' frame suspension setup which replaced the trailing arm stuff.
I'm in the process of altering my Tasmin (hopefully for the better) and would like to change to the later arrangement.
Could anyone who can help, email me with what info they have. [e-mail]

Thanks in anticipation

IanG

[njhucker]

Sounds like an awful lot of work.
Tower View do a mod to improve the location of the trailing arm set up. This would be much easier.

[ian8542]

So do Moore Racing. The problem is the trailing arm setup is bad, even when modfied.

Ian G

[DJC1001]

The Steve Heath bible shows both suspension set ups in detail.
When I was looking for a project car I did look at the possibility of converting a trailing arm car to A frame. Decided it was not impossible but not practical unless you have full welding and jigging facilities - even then I would give it a miss and just uprate the trailing arms as per. previous reply.

[AM400]

Have a word with Tasmania, he change his set up on the racer to A frame from trailing arm, not sure if this was done through Moore racing though.

Andy.

[wedg1e]

Here's a thought: the Lotus Esprit uses essentially the same setup as the trailing arm TVRs. Post 1981-ish, the Esprit gained a top suspension link, thereby relieving the driveshaft of the task of keeping the hub located. The Esprit also has CV rather than Hookes-type UJs (allowing some 'telescoping' of the driveshafts I suppose).
Lotus used that setup for years and nobody doubts the handling of an Esprit ; maybe worth looking into modifying the TVR that way?

Ian

[Boosted LS1]

Not sure about the underpinnings on the tvr but I converted my own car to 'A' frame location and it entailed a huge amount of work. Firstly I had to take a lot of measurements and then make 3 jigs accurate to a couple of millimeters. The first jig was used to accurately place the mounting points for trailing links etc. The second jig was used to fabricate the 'A' frame itself and a third jig was used to fabricate brackets to the axle. I ended up with an 'A' frame which mounted to the bulkhead behind the seats and located under the diff housing via a spherical bearing. Above the axle I have 2 trailing links going rearwards mounted to the chassis rails with a spherical bearing at one end. It was one of the best mods I ever did and transformed the car's handling The rear roll centre is much lower with this mod and I get a lot more traction. It must be worth considering if your not happy with the tivver's back end.

[ian8542]

I've had a chat with Mike Williams in the parts dept at TVR. (Very helpful. Also a car club member i believe and older TVR owner).I meant the car not Mike !
They still have the jigs for the 'A' frames, one size quoted is 469mm and the other 472mm. For different year builds apparently. (life is never easy!)
I've also ordered a pair of uprights/bearing carriers (in stock ).
What i will do is have the tie rods made but i am looking at mounting them differently, as it appears as if the tie rods in standard trim are positioned forward of the driveshafts which i have been told is not good.
If anybody needs any part no's or would be interested in a brand new pair of standard, all steel and powdercoated trailing arms, get in touch before i send them back to the factory.

Ian G

>> Edited by ian8542 on Friday 19th March 18:52

[andy390]

Ian,how did you get hold of the guy at TVR. i,ve always believed thet their numbers were never given out?? Cheers
Andy

[shpub]

The Tie rods have to go forward because there is no where else to mount them. There are no rear chassis points to use. It is also the usual method of fixing them. Interestingly, the front suspension tie rods went backwards but were rapidly changed to the front as well.

Positioning is absolutely critical as it basically sets the rear geometry. While there is some adjustment it is crude and time consuming to play with shims etc as they are fitted between the brake disc and driveshaft.

[danny hoffman]

Try TVR Factory 01253 509 000 Mike Day - fount of all wedge knowledge apparently

[wedg1e]

On the theme of trailing arm suspension, the front mounting bush looks suspiciously similar to the one on the Esprit, so if you're struggling to find one, try SJ Sportscars down in deepest darkest Devon. £13.75 + the usual.

Ian

[ian8542]

andy390 said:

Ian,how did you get hold of the guy at TVR. i,ve always believed thet their numbers were never given out?? Cheers Andy

I usually just ring the switchboard and ask for Mike Williams.
I ordered the relevant parts and am waiting delivery.
Did you know there are 2 different length 'A' frames ?

Ian G


>> Edited by ian8542 on Friday 26th March 21:33