Now shocks, how to adjust on car?
Discussion
Dear all,
I know there have been many threads about new shocks but I would need some advice on setting them up. Sorry for the kind of “newbee” questions.
My car is a 1990 S3C and she is running on 18”’s with 225x40x18 tyres. Front suspension will get Poly bushes when I change the shocks.
To the question;
I have ordered new Gaz Gold Pro’s from Absolutely Shocks (excellent service) and will get them next week. I ordered 450’s in front and 375’s for the rear which seems to be in line with many recommendations here and also from Derek.
May prove a bit hard but someone on the forum who did the same choice said they soften a bit after a while
Ride height should be in the 165 to 180 interval, according to most in the Wiki. I will just have to see what I need to clear the larger 18” wheels. I will probably aim for just above 170 all around, if the wheels don’t rub…
Currently it is low….and the wheels do rub. The Konis were lower many years ago.
Anyway, I would welcome some information on how to practically adjust the ride height with the new shocks mounted. I have read most posts and I understand about parking on a level surface and how to measure under the out riggers in each corner. But;
Is there a description on the process? Can’ find one.
How much ride height change is one turn on the shocks/springs on the GGP’s?
Where do you start when you mount them? Derek said just turn them so the springs are “fixed” at maximum extension. Maybe that is the way the will be delivered.
Is the same start position used for front and back?
How do you physically adjust the shocks/springs without removing the wheels?
And if you do remove the wheels the car will have to be moved to regain the right position every time an adjust met is done, right? This will make the exercise pretty time consuming I guess.
When you measure ride height, do you place a weight in the driver’s seat to compensate?
Do you also put some weight in the passenger seat to compromise for potential passenger?
Is a wheel alignment always needed after changing the chocks and potential ride height?
Kind regards
//Rob
I know there have been many threads about new shocks but I would need some advice on setting them up. Sorry for the kind of “newbee” questions.
My car is a 1990 S3C and she is running on 18”’s with 225x40x18 tyres. Front suspension will get Poly bushes when I change the shocks.
To the question;
I have ordered new Gaz Gold Pro’s from Absolutely Shocks (excellent service) and will get them next week. I ordered 450’s in front and 375’s for the rear which seems to be in line with many recommendations here and also from Derek.
May prove a bit hard but someone on the forum who did the same choice said they soften a bit after a while
Ride height should be in the 165 to 180 interval, according to most in the Wiki. I will just have to see what I need to clear the larger 18” wheels. I will probably aim for just above 170 all around, if the wheels don’t rub…
Currently it is low….and the wheels do rub. The Konis were lower many years ago.
Anyway, I would welcome some information on how to practically adjust the ride height with the new shocks mounted. I have read most posts and I understand about parking on a level surface and how to measure under the out riggers in each corner. But;
Is there a description on the process? Can’ find one.
How much ride height change is one turn on the shocks/springs on the GGP’s?
Where do you start when you mount them? Derek said just turn them so the springs are “fixed” at maximum extension. Maybe that is the way the will be delivered.
Is the same start position used for front and back?
How do you physically adjust the shocks/springs without removing the wheels?
And if you do remove the wheels the car will have to be moved to regain the right position every time an adjust met is done, right? This will make the exercise pretty time consuming I guess.
When you measure ride height, do you place a weight in the driver’s seat to compensate?
Do you also put some weight in the passenger seat to compromise for potential passenger?
Is a wheel alignment always needed after changing the chocks and potential ride height?
Kind regards
//Rob
sebackman said:
I would need some advice on setting them up.
...
I have ordered new Gaz Gold Pro’s from Absolutely Shocks (excellent service)
That's a long question, which would need a huge reply to answer properly....
I have ordered new Gaz Gold Pro’s from Absolutely Shocks (excellent service)
The short answer is that you should talk to Derek to find out what initial settings he recommends and his recommended procedure for fine-tuning afterwards. Presumably you have already discussed your car and driving requirements so that he can spec the most appropriate parts for you.
Slightly longer answer - be very cautious about playing with ride height changes since it alters the suspension geometry and can have a profound affect on the handling. I recommend you keep the car close to the original OEM height unless you understand the issues or aren't concerned about handling. To change the height you will absolutely need to take the wheels off, you will need to move the car around to settle the suspension and re-measure until you get the height you want. You need to check the geometry afterwards but small height changes aren't going to throw things out significantly. Do not under any circumstances try to set the two sides to different heights to try to level the car; always ALWAYS set left and right spring seats on an axle to the same position relative to the damper body. If the car does not sit flat at that, either there's something wrong with the car or something wrong with the way you're measuring it, and adjusting the spring seats isn't the right way to deal with either problem
Edited by GreenV8S on Sunday 11th June 13:52
Totally agree with GreenV8. I am going to add a bit of controversy as well.
Your S will never ride right for the road with those wheels/tyres. I even believe it is potentially dangerous. The TVR chassis was about the only bit reasonably well designed and it was developed from racing experience. That experience was with tyre with a fair degree of compliance. In other words the tyres are part of the suspension. Your tyres have very little compliance anyway and with the light weight of the S they will very little suspension effect. Apart from the very harsh ride they will put all the suspension load onto the limited travel suspension.
The originals are 15" not 18".That is a massive change in compliance.
Furthermore I would be amazed if the roll centre of the wheel (not the car) is the same and whether the effective offset (when cornering) is the same which puts loads in different places. What is the unsprung weight of this big wheels/tyres compared to the originals and how does that affect the suspension compliance when you hit a pothole?. How does the giroscopic effect affect the steering and the load on steering components, the column is unusually tightly angled and comparatively lightly attached to the bulkhead? The steering is all off small cars.
The S is at its best on twisty roads, they tend not to be the best surfaced and you will want to cross the centre line a lot. Big fat hard low profile tyres 'tramline' more. You might ultimately get more cornering grip in the dry, but less fun overall.
Will the 'envelope' made by the wheel at all stages of lock and all stages of suspension compression and bounce clear the bodywork and components. You cant just jack it up to clear the wheels, that alters the geometry and the position of the envelope.
You are reducing the downforce between wheel and surface by a significant degree. It is a light car. If you drive it in the wet that contact force is important, counter-intuitive perhaps but those big wheels are more likely to aquaplane and slower to recover.
A smooth dry track with 18's might be possible but if you are driving it on the road where compliance is already an issue I think you are asking for trouble.
If you want a modern hot hatch performance then buy one, dont bugger up a good classic car
Now, let battle commence, I am putting my head down!
Your S will never ride right for the road with those wheels/tyres. I even believe it is potentially dangerous. The TVR chassis was about the only bit reasonably well designed and it was developed from racing experience. That experience was with tyre with a fair degree of compliance. In other words the tyres are part of the suspension. Your tyres have very little compliance anyway and with the light weight of the S they will very little suspension effect. Apart from the very harsh ride they will put all the suspension load onto the limited travel suspension.
The originals are 15" not 18".That is a massive change in compliance.
Furthermore I would be amazed if the roll centre of the wheel (not the car) is the same and whether the effective offset (when cornering) is the same which puts loads in different places. What is the unsprung weight of this big wheels/tyres compared to the originals and how does that affect the suspension compliance when you hit a pothole?. How does the giroscopic effect affect the steering and the load on steering components, the column is unusually tightly angled and comparatively lightly attached to the bulkhead? The steering is all off small cars.
The S is at its best on twisty roads, they tend not to be the best surfaced and you will want to cross the centre line a lot. Big fat hard low profile tyres 'tramline' more. You might ultimately get more cornering grip in the dry, but less fun overall.
Will the 'envelope' made by the wheel at all stages of lock and all stages of suspension compression and bounce clear the bodywork and components. You cant just jack it up to clear the wheels, that alters the geometry and the position of the envelope.
You are reducing the downforce between wheel and surface by a significant degree. It is a light car. If you drive it in the wet that contact force is important, counter-intuitive perhaps but those big wheels are more likely to aquaplane and slower to recover.
A smooth dry track with 18's might be possible but if you are driving it on the road where compliance is already an issue I think you are asking for trouble.
If you want a modern hot hatch performance then buy one, dont bugger up a good classic car
Now, let battle commence, I am putting my head down!
I would also emphasize that ride height measurements must always be taken from the chassis - never the body.
If your measurements indicate that the car is heavy on one diagonal and light on the other, ignore any temptation to compensate by jacking up on the diagonal because the problem is almost certainly that the ground is not flat.
Even if the ground looks perfectly flat, assume it isn't until you have measured it properly, for example with a spirit level or water gauge. Discrepancies large enough to throw your measurements are simply not visible by the naked eye over the width of a car.
If your measurements indicate that the car is heavy on one diagonal and light on the other, ignore any temptation to compensate by jacking up on the diagonal because the problem is almost certainly that the ground is not flat.
Even if the ground looks perfectly flat, assume it isn't until you have measured it properly, for example with a spirit level or water gauge. Discrepancies large enough to throw your measurements are simply not visible by the naked eye over the width of a car.
Edited by GreenV8S on Saturday 17th June 02:43
Agreed, damn near impossible on the ground. We used a very good garage 4 post ramp and even checked that. Note GreenV8 says the chassis NOT the outriggers. If you can find a car with outriggers all perfect then show me! Even the chassis may not be perfect. On a ramp you can set it up by outriggers first to get it roughly right, then check chassis and then check the suspension arms are at the same angle...if not, why not? At the end of the day it is the suspension you are setting up so 'perfect' alignment of the chassis outriggers is **** all good if the suspension then isnt equal.
Yes it does need 'body' weight in the car. So if you use it typically 1 up and occasionally 2 up you will have to compromise.
Yes it does need 'body' weight in the car. So if you use it typically 1 up and occasionally 2 up you will have to compromise.
Hi,
Thank you for the information. Much appreciated.
The car came with 18's when I bought it back and is does look cooler with them in my opinion. And after driving on them a while I can say that they work better than your worries give reason to believe.
I did stiffen up and shorten the Konis many years ago and that has worked fine since then, also on the track. I've owned this particular car several times, but that is for a different thread.
I do have the original 15" wheels so that is covered. I understand that they can be part of the suspension and I will just have to see how big the difference is after some laps.
The wheels do touch at extrem steering angles but just barely. I'm not too worried about that.
I got the GGPro's today so next week I will mount them.
I will set ride hight as advised on an even surface and with driver/passenger weight compensation.
Upgraded brakes and a complete wheel angle setup will. be next step.
And remount the blower and intercooler. :-)
Thank you.
//Rob
Thank you for the information. Much appreciated.
The car came with 18's when I bought it back and is does look cooler with them in my opinion. And after driving on them a while I can say that they work better than your worries give reason to believe.
I did stiffen up and shorten the Konis many years ago and that has worked fine since then, also on the track. I've owned this particular car several times, but that is for a different thread.
I do have the original 15" wheels so that is covered. I understand that they can be part of the suspension and I will just have to see how big the difference is after some laps.
The wheels do touch at extrem steering angles but just barely. I'm not too worried about that.
I got the GGPro's today so next week I will mount them.
I will set ride hight as advised on an even surface and with driver/passenger weight compensation.
Upgraded brakes and a complete wheel angle setup will. be next step.
And remount the blower and intercooler. :-)
Thank you.
//Rob
mine runs 17s with no real problems.
I've extended the suspension top mounts and use Griff Bilsteins along with 450 /375 springs and although a little lower than most it doesn't bottom out too much
[url]
|https://thumbsnap.com/UOLEHiJ4[/url
saying that it is lower than Willies S - mine on left ( Willies running standard 15s)
I've extended the suspension top mounts and use Griff Bilsteins along with 450 /375 springs and although a little lower than most it doesn't bottom out too much
[url]
|https://thumbsnap.com/UOLEHiJ4[/urlsaying that it is lower than Willies S - mine on left ( Willies running standard 15s)
Edited by magpies on Saturday 17th June 00:30
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