clubstylus

Ride height for Road
My car seems high at the front - this may be on purpose for SVA, I bought the car as a rolling chassis from SSC.

Please can you tell me what the ride heights should be front and rear, for road use; where you measure it from (a chassis rail to ground? which rail/s?) and....how to adjust the ride heights!!

I assume you must do something with the springs to adjust the right heights, I do not know as not dealt with that side of things before (protech shocks).

My car came with 180 front 130 rear springs - length I do not know. I will change these and probably from the previous posts to 240 front, 200 rear (I'm a bit heavy - not fat just 6'2" ex rugby player, but getting a little lardy). Spring lengths depending on shocks and replacing the rear trailing arms I assume for ride height?

I did draw a replacement bottom trailing arm, bent to allow for longer shocks, based on measurements from my car with a view to getting a price to get a few made - the file corrupted and I have not had time to re do it yet, I hope to get some time later this summer. Once the car is on the road I want then to get a few issues sorted:
Fit escort uprights etc...sourced thanks to MattD (in box still, not been opened!!).
Upgrade front springs.
Get the rear trailing arms changed.
new shocks and springs for rear.

The information on ride heights are my current pending issue - I have seen posts on this forum concerning then, but where to measure and how to alter,
Q.

OK First thing to say is where to measure.

FRONT = under the lower 50mm x 25mm chassis tube centre.
REAR = Under where alluminium sheet meets steel seat pan on a 25mm tube. If that tube is welded on the underside as opposed to the inside of the cockpit THEN measure to the rear of it ok

HOW = underneath the springs on the shock absorbers there are alloy spring seats ---- they can be wound UP or DOWN .

HEIGHT = as a base to start with, the rear needs to be 25mm higher than the front. This is what controls understeer / oversteer . This setting will induce oversteer under provocation/heavy foot You can then fine tune the car's charactoristics to your style of driving as you become more confident.Many other things can effect oversteer/understeer BUT this has the greatest effect. If you're a big chap then tyres should be 20psi all round. Whatever shock settings you have(ie. total clicks) Set the front shocks to 1/3 rd total clicks and rear at 2/3 rds total clicks.
The springs you have at the rear (130lbs = sell them) If you ARE really a big chap sell the 180's too
200 REAR 225 FRONT PLUS ARB or heavier up front and no ARB --- obviously I'm biased towards an ARB cos I make em but it would make a better road set up and occasional trackday combination. The 180 rear , would be fine for road if you weighed only 10 to 12 stone .

A WORD OF WARNING When you've set the car up with these guidelines , check how much '' shock absorber '' piston can be seen with the cars weight fully on it's wheels . If the front has 15 to 20 mm as well as it's bump stop , all will be well. The rear really ought to have 30 to 50 mm. IF NOT then you will need to change the shocks to achieve it.
The greater the spring poundage , the finer you will get away with. However , the greater the poundage the less tolerant the car will be to your driving It's not an exact art.
Not sure what shock lengths/springs you have but a guide for a road only car would be chassis height FRONT = 130 to 160 mm PLUS 25mm higher at the rear measuring point.

Hope this helps ---- it's easier to give an answer if I could see rather than answer someone elses diagnosis though

Wow - that is excellent and thank you for it. - I think you should put it on the web site on the car set-up part as it would be a good positive addition to what is already there.

Thank you again.

I will measure the front lights to see if I can lower the front to get it near where it needs to be and raise the rear as per the details; at the moment I am pointing into space when I am sitting in the car and I do not want any accidents on the way to SVA!!

we have just done our lights on the front. the indicators come at 350mm excatly if they are just below the bumber line with the shocks as low as they will go, so you should be fine. depends on where they are though!

I sunk in my indicators (old mini/landrover style) centred on or just above the mould line to give a margin on the SVA requirement. I should have a reasonable amount of distance to play with.