GT6 Dampers - Koni

[heraldcoupe]

Posting this one on behalf of a friend.

Rebuilding a GT6 Mk2 with Canley's CV joint rear axle conversion. Dampers are Koni, bought as specifically fitting the original GT6 application - they don't.
The car was rebuilt with original damper mounting points rather than the popular chassis-mount conversion brackets, as the dampers were supposed to fit in this application.

There is the obvious option of retro fitting the chassis brackets, however given this is an as-new build where the bodywork has been fully painted and assembled, it would be the course of last resort.
Can anyone offer a part number for a Koni damper which will either fit the original wheelarch mounting point, or one which will fit between the Rotoflex vertical link and the standard chassis mounting point used on the Mk1 and other non-Rotoflex cars. Without the doughnuts in the way, the damper should clear the drivetrain between these points, but will a damper to Herald/Spitfire dimensions fit in terms of extension and compression? If so, is there a Koni number?

I know this should all cross reference with Triumph suppliers, but to date I've seen several supposedly correct sets supplied for this car, none of which fit according to their specification.....

Cheers,
Bill.

[GT64fun]

Hi Bill

When rebuilding my Mk2 GT6, we abandoned the wheelarch mount and fabricated brackets to fit onto the original chassis mounts. These are essentially similar to some of the available 'conversion' brackets but with an offset to place the damper vertically above the mounting point on the vertical link and position the top slightly further outboard.

Without the offset the damper leans forward a bit, which can put a strain on the bushes. See attached PDF sketch.

We welded the brackets to the chassis, but they could be configured to allow bolted retrofit into a completed vehicle.

The 80-1717 Koni damper was listed as being from  a 'lowered classic Mini' so probably best to search via Mini specialists.

The ride is actually very good with the Konis, so probably worth persevering.

Hope this helps.

Ian F ;)

[herald948]

Bill, if this helps any...from the Koni web site:

Data for rear shock, NON-Rotoflex: 5/8 bolt; 12 - 9 5/8 travel range

Data for rear shock, Rotoflex: 1/2 bolt; 14 - 9 1/2 travel range

I can't vouch for the accuracy of this, but I can vouch for the fact that Koni says the Rotoflex rear shock are N/A. :(

[hypoid53]

As Ian said, the 80-1717 is the correct length with 8.5" closed to 12.5 " open for rotoflex cars using the chassis extension brackets.  Originally a Mini Cooper fitment, no longer made apparently, but Mini specialists might still have some. You need to change the bushes of course. A search of the archives will give you a great deal more information as it was well covered some years back. The TSSC supply a special Gaz shock which meets these dimensions. Most other supply standard size Spitfire shocks which are too small for this application and will bottom out.

[black_rover]

heraldcoupe wrote:

...
Can anyone offer a part number for a Koni damper which will either fit the original wheelarch mounting point, or one which will fit between the Rotoflex vertical link and the standard chassis mounting point used on the Mk1 and other non-Rotoflex cars. Without the doughnuts in the way, the damper should clear the drivetrain between these points, but will a damper to Herald/Spitfire dimensions fit in terms of extension and compression? If so, is there a Koni number?...

Bill, I have the Jones/Bowler CV conversion on my GT6 and have fitted Koni dampers to the rear, using the standard chassis mounting point (as per non-rotoflex cars) The Koni part number I used is 80-1389
It seems to work well without bottoming out or restricting travel too much.

[Tim Bancroft]

Totally agree with Steve's reply.

I still have my shockers on the (mk2) original mounts, could'nt afford to buy new shockers to suit the (say) mk1 position. But when I replace I will fit mk1 shockers, probably Koni.

[Anthony]

Could someone confirm the part numbers needed for a MKIII with CV conversion?

It sounds like the fronts are the usual 80-1388

But what about the rears?
I've heard two different numbers

80-1389 (originally for a MKI)
Or
80-1717 (originally for a Mini)


Maybe I should just use the Spax I've already bought? :)

[Anthony]

Another question  :B


When taking measurements of the dampers, where are they measured from?

Are you measuring just the body of the damper, or are you including the mounting eyes?
And if you measure the eyes, are you measuring from their centres, or are you measuring their complete/total lengths?

Sorry for (all) the daft questions

[hypoid53]

Measure from the centres.

If you are using the original chassis top mounts (and it it seems that you are) then its Koni 80-1389.

80-1717 are for when you are using the chassis top extensions, which are only required if still on rotoflex (which you are not).

[Anthony]

Thanks:)

My limited knowledge tells me I should use the chassis extension brackets if possible, as that will mean the damper is fitted in a more vertical position

I've got a spare pair of brackets, so I think I should probably go that route

I doubt the extra weight of the brackets will make the slightest bit of difference to me

[Anthony]

Just measured the two sets of Spax I have here

Both sets are for rotoflex cars with the extension brackets

They measure 13" when opened, and 10" when closed

(measured from centre to centre)

So they should be more likely to bottom out than the Konis based on the figures quoted in this thread

I notice the Spax have bump stops fitted..........Do the Konis have them as well?

[Anthony]

Final question......or is it? ;)


What effect will a lowering block have on the suspension travel and the required shock length?

Will I be ok using a lowering block with the Mini dampers?
Or are there problems with this?

[Martins Stag]

Not sure if this help but I have Cv's on my Spitfire with Shock absorber brackets and I always has Shock absorber "bottoming out " issues.
Mark at Jigsaw provided some very short Shockers by GAS. I think there compressed length was 8.25 inches. I can't check as I am on holiday at the moment. They work very well and even the wife noticed the improved ride.

[BrendanD]

4502 wrote:

They work very well and even the wife noticed the improved ride.

Oooo Errrr   :X
What is this 'Carry on Triumph'?  ;)

[Anthony]

4502 wrote:

Not sure if this help but I have Cv's on my Spitfire with Shock absorber brackets and I always has Shock absorber "bottoming out " issues.
Mark at Jigsaw provided some very short Shockers by GAS. I think there compressed length was 8.25 inches. I can't check as I am on holiday at the moment. They work very well and even the wife noticed the improved ride.

Thanks mate

Are you saying your car stopped bottoming out with the shorter shocks

Or

Do they still bottom out with the short shocks too?

[Martins Stag]

Sorry just to clarify with the new shock absorbers they didn't bottom out but with the TSSC shorter ones they did. Apparently my car sits quiet low at the back and this has resolved it.