MG TF Shock Absorber and/or Spring Dimensions

Hello! I've been a lurker for the past few months but now I need some help so here it is - the first post.

I'm looking at doing some shock absorber development for the TF very soon. Although, to do so, I need some measurements of some normal shocks and springs. Of course, I have my set, which are on my car, but I'm not in a position to take them off at the moment.
Does anyone have any measurements, or maybe they could be so kind as to take some, of any type of shock for the TF, be it OEM, Spax, Bilstein, GAZ or whatever. Measurements of any springs would be wonderful too.

I'd be looking for the total free length, the closed length (and therefore the travel), the diameter of the shock absorber itself, the inner and outer diameters of the spring, the free length of the spring, the diameter of the rod and anything else that people have/can get.

(Hopefully) thanks in advance,
All the best,
James

:welcome2:

Sounds interesting. :yesnod:

Thank you.

Yes, it should be a very interesting project indeed.

I've now noticed there's possibly a difference between the front and rear shocks, so if anyone knows anything on this, that'd be a great help too.

James

I have recently replaced the rear suspension units on my 04 TF. Here are the old ones. They are original Rover Monroe units . I can take measurements from them if you can be specific about exactly you want although I am not about to dismantle them to get information like free spring length. Does that help?

Hello and thank you for offering to help. No worries about not disassembling them, any help is greatly appreciated!

I've attached a picture displaying the dimensions I may find helpful.



1 - The free length from the centre of the lower bolt hole to the very top of the shaft (parallel to the shock axis).
2 - The distance between the centre of the bolt hole and either the top or bottom of the lower spring plate (Please specify which you use).
3 - The length of the spring, from top of lower plate to bottom of upper plate.
4 - The outer diameter of the spring at the top of the spring.
5 - Both the lengths of the clean section where the bushes sit and the length of the threaded section.
6 - The diameter of the clean section where the bushes sit.
7 - The distance, end to end of the lower joint.
8 - The diameter of the lower through bolt.

Thank you very much for your help.

Still required would be measurements 1, 2 and 3 (from the left) for the front shocks. Also the travel of the shocks/closed lengths for both the front and rear.

OK. I've measured my old rear suspension units. I am not sure how the fronts differ.

1 - Free length: 359mm
2 - Bush centre to bottom of lower spring plate: 76mm
3 - Length of spring: 211/212mm
4 - Outer diameter of spring at top: 91.5mm
5a - Length of unthreaded top: 29/30mm
5b - Length of threaded top (inc nut): 32mm
6 - Diameter of unthreaded top: 14mm
7 - Length of bottom bush: 57mm
8 - Bolt Diameter: 12mm (see note)

Note: The bolt diameter is actually ~11.8mm but the bush internal diameter is ~13mm. The bolt is very loose in the bush. As far as I can ascertain, this is normal. When assembled, the bush apparently sits into s depression in the bottom bracket.

I'm afraid I cannot help with the front units as I haven't replaced them. As for the range of compression of the damper, I cannot measure this without removing the springs. Unfortunately, I don't have the tools to do this. If you are close to Billericay you are welcome to come and investigate for yourself!...

I hope this helps with your project

That's great, thank you very much.

No worries about the front as I managed to get a front shock off today to get some measurements! Having these details about the rear will really help though, so that's great, thanks.

I also noticed that about the bolt, seems odd but it obviously works. It must work off the clamping force more than the bolt shear force - clever, I suppose.

Thanks for the offer, but I'm afraid I'm a fair way from Billericay. Belgium, in fact. :yesnod:

Again, that's helped a lot,
Thank you very much,
James