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TR4/4A TR4A rear suspention question

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Adrio

Jedi Knight
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I in the final stages of a multi year TR4A IRS rebuild and have a question I hope someone has the answer to. I an looking for the rear coil spring specifications for the TR4A IRS. In particular I would like to know the free length (how long the spring is when not in the car), the coil diameter, the number of working coils, and the wire diameter.

Basically, the problem I have is I bought the car in parts and I have more parts then the car needs and some parts are not for the TR4 and some are missing. I can't tell from the information I have if the springs I have are correct and which are front and which are rear.

Any help would be great.
Adrio
 
Hi Adrio, the long ones are the front springs, 11 inches free height plus a metal spacer piece, or slightly longer on cars without the spacer. I will answer the rest of the question on Monday after I check on mine.
I have uprated and slightly lower springs, but also have a stock set so will try to give you all the info.
If you think the springs might be old or have sagged I would replace them, as they are not that expensive, and easier to do while its all apart. You might also be able to look this up on the VTR website where there is some tech info.
Simon.
 
Height of the front springs is 10.2 inches with the rears being 11.5, assuming that the TR4 IRS uses the same springs as the TR 250 and TR6 which appears to be the case from looking at the part numbers. I'd have to dig around to actually measure the diameters, but the rear springs are taller and just a bit smaller in diameter than the fronts.

Hope this helps.
 
Thanks to both of you (Simon and Don). This is a big help. My guess is I have a bunch of new front springs and uprated and lowered ones at that. The two sets that I have for the "back" (I say that because the front were already on the chassis when I bought the project) are new and one set is 8.75" long with 0.565" wire and the other set is 9.25" long with 0.535" wire.

The comment that the rear are slightly smaller in diameter aslo makes me think I have front ones because the rear packing pieces seem too small for the springs.

Adrio
 
Adrio,

I will try to dig out a set Sunday and get the outer diameter of the coil and the wire diameter itself of both the front and rear stock springs. Sorry I cannot help you with the sizes of the aftermarket variety. The new stock raod springs are not expensive; somewhere around $30 - 35 US each. I would part with a clean, no-sag, original set for half that but I have no idea what the shipping is north of the border. On the other hand, with what you are doing, new is probably better.

Simon, you had me wondering if I installed the new ones bass-akwards. Would have been a true double YIKES as I just detest doing the front springs. It is no big deal to do the R&R but for some reason I just do not like doing it even with the body off!
 
Hi,

I think the 9.25"/.535" springs you mention are "heavy duty/competition" front springs, to be used with the approx. 1.5" aluminum spacers. I've got a set of these on my TR4, with spacers, and ground clearance is about 5 inches (with 60-series tires on 15" Minilites).

The 11" springs are front, for use *without* the aluminum spacers. Some TR4 and perhaps all TR4A did not use the spacers with the front springs.

For stock rating on the earlier setup, approx. 10"/.505" spring was used at the front *with* the spacers. I've got two sets of these in the garage and just measured the inside diameter at 3". The heavy duty set is likely the same inside diameter, but I can't measure since they are installed on the car.

I have no IRS springs to reference.

Cheers!

Alan Myers
San Jose, Calif.
'62 TR4 CT17602L


[ QUOTE ]
My guess is I have a bunch of new front springs and uprated and lowered ones at that. The two sets that I have for the "back" (I say that because the front were already on the chassis when I bought the project) are new and one set is 8.75" long with 0.565" wire and the other set is 9.25" long with 0.535" wire.

The comment that the rear are slightly smaller in diameter aslo makes me think I have front ones because the rear packing pieces seem too small for the springs.

Adrio

[/ QUOTE ]
 
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