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#1 Identifying shocks and ride height

Posted: Wed Nov 10, 2021 10:00 am
by dlgis
Hi, the previous owner of my car fitted new rear shocks just over a year ago and the ride height seems too low to me, with the top of the rear wheel arch in line with the top of the wire wheel. Most pics of similar cars seem to have an inch or two of tyre showing above the wheel at the rear.
The new shocks are Gaz and they appear to have adjustable damping. Can anyone identify the specific shocks and advise if they have adjustable platforms to vary ride height or if it would be a case of buying longer springs to achieve this?
Thanks 😊
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#2 Re: Identifying shocks and ride height

Posted: Wed Nov 10, 2021 12:35 pm
by mgcjag
Hi Darryl.....your shocks do not look adjustable for height......looks like you also possibly have new springs....what tyres are you useing as this also affects ride height......far better to measure your height from the irs bottom plate to ground rather than useing rear wings that could have been altered over the years.....spacers are available to fit between spring and damper to raise the car......plenty of info on ride height in similar topics shown below....Steve

#3 Re: Identifying shocks and ride height

Posted: Wed Nov 10, 2021 3:32 pm
by dlgis
Hi Steve, i think you’re right that they’re not height adjustable, and the springs do indeed look new. I’ll do some proper measurements front and back when we can get it onto a four poster. And I’ll have a rummage through the other posts on this topic. Here’s a pic of the car that shows the rather low ride height. Looks like it has lead from the church roof in the boot :bigrin:
Thanks
Darryl

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#4 Re: Identifying shocks and ride height

Posted: Wed Nov 10, 2021 3:37 pm
by dlgis
p.s. tyres are standard 185x15x80 Uniroyal

#5 Re: Identifying shocks and ride height

Posted: Wed Nov 10, 2021 4:19 pm
by malcolm
Without being an expert, I must say that looks low. It's not just the height, but the angle of the car - front up.

#6 Re: Identifying shocks and ride height

Posted: Wed Nov 10, 2021 8:31 pm
by abowie
You can fit spacers between the spring and shock. C32062HA or C19027.

These will increase your rear height by an inch or so.

See these before and after shots on my 3.8 coupe.


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#7 Re: Identifying shocks and ride height

Posted: Wed Nov 10, 2021 8:33 pm
by dlgis
That’s what i think too Malcolm. I’ve already grounded the exhaust on some loose gravel, a sleeping policeman would take the thing off :sad:

#8 Re: Identifying shocks and ride height

Posted: Thu Nov 11, 2021 9:08 pm
by dlgis
Hi Andrew thanks for the heads up on fitting spacers/packing rings which could be an option although i presume is a compromise compared with having a “correct” spring length/rating.
Looking at the 2 fhcs in the pic you posted, the rear ride height on the white car looks to be similar to mine whereas the blue car looks more like I’d expect. I do need to grovel under the car with a tape measure to check the Irs to ground measurement to see if that confirms my suspension is too low, although the audible check from driving over anything bigger than a small conker suggests I do have a problem to resolve :shock:

#9 Re: Identifying shocks and ride height

Posted: Thu Nov 11, 2021 9:21 pm
by johnetype
For many years the advice was don't change your rear springs from the original ones as the new replacements available wouldn't give you the correct ride height.

More recently I seem to recall seeing an SNG advert saying they'd had new springs made that were correct so might be worth checking out.

That said, there's no real compromise in using spacer/packing rings for a small adjustment as long as the spring rate is correct.

#10 Re: Identifying shocks and ride height

Posted: Thu Nov 11, 2021 10:52 pm
by abowie
What John says is correct.

Correct replacement springs for E types have not been available in the past.

We have fitted the spacers to a number of cars that were low at the back, and it works well.

I did notice recently a company in the UK saying that they make springs correct for all models. I can't remember their name offhand, but I did post about them in another thread a couple of months ago.

#11 Re: Identifying shocks and ride height

Posted: Thu Nov 11, 2021 11:18 pm
by mgcjag
Just a note that there is no correct rear ride hight measurement for S1/2 cars in the Jag service manual...there is a rear measurement in the S3 manual.........personaly i have in the past used springs from SNG that have given a rear ride height that "looks" ok..........CMC also had springs that were supposed to be correct...i havent tried them..Steve

#12 Re: Identifying shocks and ride height

Posted: Thu Nov 11, 2021 11:26 pm
by Series1 Stu
abowie wrote: ↑
Thu Nov 11, 2021 10:52 pm
I did notice recently a company in the UK saying that they make springs correct for all models. I can't remember their name offhand, but I did post about them in another thread a couple of months ago.
Is this them, Andrew?

https://britishclassiccarparts.com/prod ... spring-set

Regards

#13 Re: Identifying shocks and ride height

Posted: Fri Nov 12, 2021 3:56 am
by 34232
Slightly off topic however I also have the rear shocks and springs out of my 68 S1.5.
I had expected that the sleeve in the upper mounting bush to be slightly longer/wider than the bush itself?
That the sleeve is ‘clamped’ by the 7/16 mounting bolt and the shock together with the bush is able to rotate slightly as the wishbone swings through its arc.
However I found the opposite, the sleeve is narrower meaning the shock bush is clamped. That the sleeve is nothing more than a ‘spacer’ for the 7/16 bolt?

Can someone tell me if this is correct?
I have wondered if the bushes and or sleeve have been changed and aren’t correct.

Likewise with the lower mounts, I didn’t expect the lower bushes to be clamped onto the wishbone.
I expected that the lower bush be able to rotate. That the nyloc’s hold the special washers, but that the shaft is long enough between the shoulders, not to clamp the shock bushes.
I appreciate that the movement/rotation is minimal, however my understanding is that there is some.
Can someone please put me straight.
Thanks.

#14 Re: Identifying shocks and ride height

Posted: Fri Nov 12, 2021 6:10 am
by abowie
Series1 Stu wrote: ↑
Thu Nov 11, 2021 11:26 pm
abowie wrote: ↑
Thu Nov 11, 2021 10:52 pm
I did notice recently a company in the UK saying that they make springs correct for all models. I can't remember their name offhand, but I did post about them in another thread a couple of months ago.
Is this them, Andrew?

https://britishclassiccarparts.com/prod ... spring-set

Regards
Yes. My search abilities on this forum suck.

#15 Re: Identifying shocks and ride height

Posted: Fri Nov 12, 2021 8:15 am
by Allrand
The bolt is tightened until the sleve is clamped tight, squeezing the bush. Movement is taken by twisting of the rubber bush within the shock eye {unless polybushes have been installed which allow movement, and thus wear between the bush and eye, which is why I don't like polybushes!)

#16 Re: Identifying shocks and ride height

Posted: Fri Nov 12, 2021 8:23 am
by mgcjag
Hi Randall......yes correct re the bush being clamped.....however re the poly bushes it all depends which ones you use......The Black "Polybush" made by Polybush as sold by SNGB and others work in exactly the same way as the original rubber type bushes........beware not all polybushes are the same......Steve

#17 Re: Identifying shocks and ride height

Posted: Fri Nov 12, 2021 8:56 am
by mgcjag
Re the original posters rear height problem it should be noted that the car ride height isnt just altered by the springs....the shockes play a vital part as the spring is mounted on the shock perches......so if after market shocks are used as in this case tbe length between the spring perches and he shock mounts need to be checked...Steve

#18 Re: Identifying shocks and ride height

Posted: Fri Nov 12, 2021 11:19 am
by dlgis
Hi thanks all, looks like i need to get a shock off the car firstly to see exactly what i have in terms of shock length and spring dimensions on the Gaz shocks. The BCC springs sound like a good option to consider assuming they fit on Gaz shocks.

#19 Re: Identifying shocks and ride height

Posted: Fri Nov 12, 2021 1:05 pm
by Allrand
mgcjag wrote: ↑
Fri Nov 12, 2021 8:23 am
Hi Randall......yes correct re the bush being clamped.....however re the poly bushes it all depends which ones you use......The Black "Polybush" made by Polybush as sold by SNGB and others work in exactly the same way as the original rubber type bushes........beware not all polybushes are the same......Steve
Thanks for the info

#20 Re: Identifying shocks and ride height

Posted: Fri Nov 12, 2021 7:23 pm
by PeterCrespin
dlgis wrote: ↑
Fri Nov 12, 2021 11:19 am
Hi thanks all….The BCC springs sound like a good option to consider assuming they fit on Gaz shocks.
The adjustable-perch GAZ dampers use a different size spring AFAIK. Yours may be different?