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Dampers too short, car too heavy?
Mark Allanson - 4/9/04 at 07:25 PM

I'm using GTS dampers, and have a bit of a query about the rears. In order to get the trailing arms anywhere near parallel to the ground, I have the dampers wound right up to the limit. The car is no lightweight, but then its not particularly heavy either.

Has anyone else had this problem, any suggestions? Rescued attachment GTS Dampers.JPG
Rescued attachment GTS Dampers.JPG


rusty nuts - 4/9/04 at 08:35 PM

Would it be possible to extend the lower shock mounting , looks as if that would be fairly easy??? Rusty


Mark Allanson - 4/9/04 at 08:41 PM

I know I could adapt to compensate, I wanted to know if this is a regular problem, and if anyone has a more elegant solution


Viper - 4/9/04 at 08:49 PM

Mark
are they adjustable platforms and you are running out of adjustment?


Mark Allanson - 4/9/04 at 08:50 PM

Yes, adjustable, and yes at full extension


Mark Allanson - 4/9/04 at 08:56 PM

Tim, thinking about it, I adjusted the platforms by hand quite easily, no C spanner required. The car was jacked up on the axle so the weight was on the dampers. Do you think the springs have gone soft in the 12 months they have been on the car?


Viper - 4/9/04 at 08:58 PM

you know what i am going to say


if they are at full extension and you haven't the ride height then you have no droop either so the shocks are too short or your mounting points are wrong...


there you knew i was going to say it didnt you.


Viper - 4/9/04 at 09:00 PM

can't believe the springs have gone soft, never had that problem before, what poundage are they?


JohnN - 4/9/04 at 09:03 PM

You are screwing the platform the right way (clockwise, viewed from underneath)?? compressing the spring to raise the ride height??

If you can do that by hand you do have a serious problem or else the strength of superman

JohnN


Mark Allanson - 4/9/04 at 09:06 PM

Yes, I was clutching at straws! I cannot remember the poundage, I will check out Darrens site to check. The mounting points are spot on, as you would expect from our trade. I looked through a few of my old photo's and cannot see the problem, although the car is a little heavier now than then, but not by much - how heavy can a tank and interior be?


Viper - 4/9/04 at 09:08 PM

open chat it's easier quicker to talk..


Steve Hnz - 5/9/04 at 08:43 AM

Mark, from your pic the problem isn`t one of spring rate because the spring don`t look overly compressed so the weight should not be a problem but check the shock length between centres to confirm this. that being OK its a problem with mounts & their relationship with the shock length. If your spring is not too compressed & you`ve had to wind it up too full or near full extension to get the car to sit correctly, then your shocks are too short for your mounts or vice versa. I know which will be cheapest to fix if not easiest. Move the shock mount. Cheers, Steve.


blueshift - 5/9/04 at 12:33 PM

GTS mount their shock brackets on the rear bulkhead side tube, I forget its name.. K or M or something? I was thinking of doing the same. brackets as per book don't seem to make structural sense where they are (flappy bit of vaguely-supported metal)


MikeRJ - 5/9/04 at 06:57 PM

quote:
Originally posted by blueshift
GTS mount their shock brackets on the rear bulkhead side tube, I forget its name.. K or M or something? I was thinking of doing the same. brackets as per book don't seem to make structural sense where they are (flappy bit of vaguely-supported metal)


Glad I'm not the only one that feels it's a bit poorly enigneered around that area. I know there are thousands of cars driving around without apparent problems but it still looks weak. Even worse this is were the roll bar bolts/welds onto.


Mark Allanson - 5/9/04 at 07:27 PM

I measured everything up today, exactly as per GTS spec, I think I will have to extend the lower(axle) brackets to compensate, I think they have been designed too short!


Mark Allanson - 5/9/04 at 07:30 PM

I wont go too far with it though because if you reduce the ride height to its lower limit, this happens! Rescued attachment Bottom Ride Height.jpg
Rescued attachment Bottom Ride Height.jpg


Viper - 5/9/04 at 07:35 PM

Mark
yor springs are too short.


Mark Allanson - 7/9/04 at 08:15 PM

Do you think I should get longer springs of the same poundage or extend the lower mounts on the axle - or both? I am a little worried about having very little rebound


Viper - 7/9/04 at 08:23 PM

from what you have said and your pics it seems to me that your springs are too short. as for poundage does its a bit of a guess till you drive the car, if you put longer springs on then you won't need to wind up the platforms as much to get the same ride height, for what springs cost i would buy some longer springs before hacking the mounts about, most companys will exchange the springs if they are wrong anyway..
Tim


Mark Allanson - 7/9/04 at 09:34 PM

Any recommendations before i google?


Viper - 7/9/04 at 09:45 PM

Hmmmm only the shock manufacturers or demon thieves etc....


Mark Allanson - 7/9/04 at 10:00 PM

8" by 180lb seems like a decent choice, what do you think?


Viper - 7/9/04 at 10:09 PM

spring rates, has to be your guess, i suppose you could ask others with a similar set up to you what rates they found worked, length...i would suggest that if you just need to compress the spring to fit it onto the damper then that would be a good starting point
Tim


Mark Allanson - 7/9/04 at 10:12 PM

There is 3/4" gap when full extended, an 8" spring would only need a 1/4" compression to fit. nice and snug, without being silly?


Viper - 7/9/04 at 10:17 PM

i am guessing you have a 7" spring on there now and you have to wind the platform to the max ......do you know anyone that can lend you a 9" spring? poundage doesnt matter to see if the ride height is gonna work. what length have you on the front?


JoelP - 7/9/04 at 10:24 PM

without some pre load there is always the risk of the collar falling out in rebound. mine did whilst i was experimenting (in the garage!), so i preloaded it as much as i could by hand.


dozracing - 10/9/04 at 08:10 AM

Hi Mark,

You have U2U explaining everything!

Would have been quicker to email me at:-
darren@gtstuning.co.uk or called me
07770 405 688
01795 590295

Kind regards,

Darren