Page 1 of 1

Adjustable spring platforms and HTPs

PostPosted: Thu Apr 14, 2016 7:15 am
by batfish
Can anyone confirm what the have done to make the adjustable spring platforms comply with FIA appendix K. I have been told that in order to get the HTP they now have to have a weld all the way around the platform.
Before I get this done I just would like to check that this is actually being done.
I would have had a look at the Elans at Castle Combe this weekend but I am off the the World Endurance race at Silverstone.

regards

Andy

Re: Adjustable spring platforms and HTPs

PostPosted: Fri Apr 22, 2016 11:51 am
by batfish
I have now been told by one of the MSA,s registrars that even welded up spring platforms are not allowed and the original spring seat must be used.
2 issues the with that
Surely the original rear spring platforms will clash with the allowed 6 inch rims
All front shocks I have seen of race spec have adjustable platforms,anyone seen a race shock with a fixed platform?
Also the front shocks cannot have a rose joint at the bottom they have to be the original bush type.
Interesting

Andy

Re: Adjustable spring platforms and HTPs

PostPosted: Fri Apr 22, 2016 4:47 pm
by nmauduit
would fixed size spacers (removable sleeves) of adequate length be acceptable under current FIA rules?

Re: Adjustable spring platforms and HTPs

PostPosted: Sat Apr 23, 2016 9:25 am
by vstibbard
If its original 26R they a referring to then, I have the split alloy spacers that were with my car, the two halves are placed on the fixed platform and wired together to reset ride height, these were on the front adjustable Armstong damper/spring unit and rear shock tubes.

Cheers

V

Re: Adjustable spring platforms and HTPs

PostPosted: Mon Apr 25, 2016 9:30 am
by batfish
V

Thats interesting, would you have any photos of the spacers?
I thought the original platforms on the rear would clash with the homologated wheels and tyres, am I wrong about that.

Andy

Re: Adjustable spring platforms and HTPs

PostPosted: Mon Apr 25, 2016 12:28 pm
by vstibbard
Hi, the rear struts do not have the large diameter springs, they use a smaller diameter with a simple flat flange on the tube, the alloy pacers sit on the flange to raise the ride height. I'll take some photo's tomorrow when I'm up at the shed.

Cheers

V

Re: Adjustable spring platforms and HTPs

PostPosted: Mon Apr 25, 2016 9:00 pm
by elj221c
batfish wrote: The original spring seat must be used.
Surely the original rear spring platforms will clash with the allowed 6 inch rims
All front shocks I have seen of race spec have adjustable platforms,anyone seen a race shock with a fixed platform?
Also the front shocks cannot have a rose joint at the bottom they have to be the original bush type.
Andy


Andy, I think that the original rear spring platform was used but reduced in diameter to support 2.25 springs, as were mine.
The original equipment front shock was an Armstrong AT9 according to my ageing notes and indeed were not Rose jointed. (UK patent 'aquired' from H G Heim after the war given (?) to Rose Bearings)

rear-suspension-detail..jpg and


I have alloy spacers, not shown, made up by Banks (Koni dealers, engineers) years ago but not split.

I had to take it all apart again to fit them.

Re: Adjustable spring platforms and HTPs

PostPosted: Wed Apr 27, 2016 12:03 pm
by batfish
Just spoken to TTR they have a front shock absorber that has been accepted by the FIA and a collar for the rear strut.
Should be problem solved, hopefully
Anyone want to buy a pair of Kelvedon front shocks with adjustable platforms?
Thanks for the replies much appreciated

regards

Andy

Re: Adjustable spring platforms and HTPs

PostPosted: Wed Apr 27, 2016 1:35 pm
by nmauduit
batfish wrote:Just spoken to TTR they have a front shock absorber that has been accepted by the FIA and a collar for the rear strut.
Should be problem solved, hopefully
Andy


Would it be possible to post photos of the parts currently accepted by the FIA at your convenience? thank you !

Re: Adjustable spring platforms and HTPs

PostPosted: Sun May 15, 2016 9:44 am
by batfish
attached photos of what the MSA registrar tells me is acceptable, these appear to be internally threaded sleeves with platforms welded on at the required heights.

regards

Andy

Re: Adjustable spring platforms and HTPs

PostPosted: Tue May 17, 2016 1:14 pm
by nmauduit
batfish wrote:attached photos of what the MSA registrar tells me is acceptable, these appear to be internally threaded sleeves with platforms welded on at the required heights.


thank you Andy, quite interesting to have a current registrar opinion - though I'm not sure I get how the pictured system would be threaded for adjustment prior to welding: I don't see a thread on the black tube (or it would be very fine, which would be rather weak to hold the car weight even statically to set up body height)...

Re: Adjustable spring platforms and HTPs

PostPosted: Sat Jun 04, 2016 7:45 pm
by batfish
Bxxxxxr

Welded on the rear spring platforms at correct heights after corner weighting the car, did not check for tyre clearance, Guess what, too close to the tyres, I need to raise the platforms approx 60mm to give enough clearance. . Is it just a case of getting new springs 60mm shorter to suit the repositioned spring platforms or is it more a completed calculation to find the correct length of spring required for the new platform height . I use 170lb rear springs

regards

Andy

Re: Adjustable spring platforms and HTPs

PostPosted: Sat Jun 04, 2016 10:57 pm
by vstibbard
Hi Batfish, not surprising, the photo of the acceptable platform is as per the original fitted to my 26R.... fine tuning ride height by via split collars. I caught up with JimBertram recently he prepared and raced my car from new, he said they kept paired springs and split collars for changes based on track (rough v's smooth) and long distance races where they used long range tank and needed heavier springs.

V