Triumph Sports Cars

Well, I'm on the verge of finding out some interesting swap info.

I'm doing the Neil Revington rear TR6 upgrade, but I refuse to pay the $$$$$$ for the AVO shocks. While looking through shock specs the TR3 front shock lists as having a compressed length of just over 7". This should work perfect with the Richard Good springs. I have an old TR3 shock and sure enough, it's nice and short. I then contacted some suppliers for an up-grade shock for the TR3. Both Spax and GAZ list a shock for this application. I got the supplier to fully compress these shocks and both only went to just over 9". What gives? I don't think a compressed length of 9" will physically go in the front of a TR3. Does anyone have any info on this. They are sure they have the right shock for a TR3...

Randall,

Here is some info on Bilsteins that VW Carl posted on a 6-pack forum when I was researching the coil over conversions. The link to their page gives a lot of specs too.

Dan

Posted: Sun Apr 27, 2008 10:49 am Post subject: Re: Coil over conversion
danblackwood wrote:
Tom.
I got 12" extended, which just allows for the halfshaft to clear the frame when the car is jacked up. Lifting the hub by hand, 8.5 inches gets me to the rubber stop on the car.


Bilstein has a few shocks that fit that criteria too with a few different valvings available as well, in order to suit various spring rates.

Part numbers AK1043, AK3050F, and AK3030F are all 13.48" extended, 8.6" collapsed length, 46mm bodies with a regular t-bar to pin mount. The difference is in the valving. The AK1043 is 358# / 219# linear, the AK2050F is 131# / 206# digressive, and the AK4040F is 197# / 154# digressive. 4.88" of travel.

Then there is the AK1051 which has 393# / 172# linear valving, T-Bar to Pin mounting, 11.93" extended 7.95" collaped, and 3.98" of travel.

I think pricing is around $80 each for these, not too bad considering bilsteins rock. (KYB stands for keep your bilsteins ) Some of those might also work for the front as well. They're non-adjustable, but adjustable shocks are overkill for the street anyways.

More info on these shocks can be found in bilstein's motorsport catalog here: [www.bilstein.com]
_________________

Back in the 60's the hot shock for autocrossing a tr 3,4 was a 59 ply fury shock. But it is a very stiff shock.
mark

I almost forgot to tell you that in talking to Vern Brennon (past pres of vintage triumph club) He said that the 4 banger was first a triumph engne and then modifyed for fergason tractor..
mark

Hi Dan

Thanks for those Bilstein numbers. I spoke with the head of Motorsports at Bilstein, and all those shocks have a 46mm base tube diameter. This will not pass through the trailing arm. Bilstein has a 36mm series that will work, but none the right lengths. He was very interseted in what we were up to, and spoke to a shop that does custom work for them. They can make a custom cut-down shock for our application, complete with custom valving for $130.0 ea, plus shipping. Not bad at all. The price could come down if we had a few sets to order at once. Anybody out there interested?

I did find a stock TR3 front shock that works as is and will be using that for now, but a performance shock with custom valving would be the ultimate way to go.

Let me know ASAP.

Randall

Hi Randall,

Revington recommends that you open the hole in the trailing arm to accommodate their AVO shock, so why don't you just cut it out to 2"? That is what we did with the conversion on my car, although we used the "Blackwood Labs Kit" and not Revington's.

Ratco also does a coil over, and they use shocks with studs on both ends. Have you checked it out?

Dan

I think 2" might not be enough if you allow for the shock's movement through the suspension travel. The hole is more than a hole because it forms a web around it's edge as part of the spring pan's section through the trailing arm casting. I'd like to know what the diameter of the AVO shock is at the base. I'm guessing it's based on a 46mm standard. Opening up the hole might work, but it could leave the casting weaker.

Randall

Randall,

I will get the instructions out on the AVO's from Rev . It does say how big to open up the hole. Later today I will post the info for ya. At work right now!

Calvin

"OK"
(Instruction qoute) Using a half round file open the rough cast hole in the base of the spring pan to 50mm diameter or large enough to ensure the body of damper will not touch the trailing arm at all troughout its travel. "It also writes" 1-2 mm clearance throughout its travel should be sufficient.

So if 50mm is a starting point (which 2" = 32 thousands more than 50mm) then I believe the AVO's are around 44 to 46mm in diameter. I believe the hole can be enlarged to 2" 100 thousands and still be strong enough. I would make full ring for the top side and a full ring for the bottom w/shock mount. I would grind away the protrutions on both sides of the spring pan so that the rings seat flat. Then use 6 flat head screws just like the Rev kit (Dan and Jim used full rings which will make the spring pan stronger). 2" 100 thousands = 53.35 mm.

My end result in diameter was about 52mm =2" 47 thousands in diameter. There was still a lip in the center of the pan on the top side of the trailing arm.

Calvin

By the way Dan & Randall some great info on shocks you both have found.