Vehicle Ride Height

[ChrisH]

This will have come up somewhere in past threads I'm sure, but:

Pearl is French registered, LHD, 1989 4GTL, 1100cc, type R1128.

Measured Pearl's ride height today; Rear was 121/120 mm (L/R) difference and Front was 75/72 mm (L/R). Haynes on P.196 says this should be Rear 127mm and Front 41mm. So at the rear we are only 7mm out which I am not going to worry about, but at the front we are 31-34mm out, lower down, which may be a problem.

Question is, how critical is this?

Being 31-34mm lower at the front could be as a result of a heavy engine than that of the earlier types but Haynes does not seem to give a revised ride height in the supplement section. (I have looked - honest!). It would maybe reduce the rolling a bit by giving a lower centre of gravity, so lower maybe not a bad thing.

So, any thoughts anybody?

ChrisH

 

[malcolm]

The figures in the Haynes manual are for the 850cc cars. Renault didn't change the suspension when they fitted the 1108 engine, so the GTLs do sit lower at the front than the TLs.

There is a thread somewhere where we compared our GTL ride heights Here it is: http://www.renault4.co.uk/forum/showthread.php?t=2499

 

[ChrisH]

Malcolm,

Thanks for that. Having looked at the thread that you suggested I don't think I have a problem anymore, unless the problem is that Pearl's front should sit even lower, like at 95 or 105mm differences!

ChrisH
PS. I do like this site - just so much information available

 

[Melc]

The good bit is that if the height is the same on left and right there is no big problem, with handling. if the sides are out, the car will handle like a broken skateboard.The front has another variable, the angle of the driveshaft operation. Theoretically if too high or low, the driveshafts wear due to operating at acute angles for longer periods.

 

[angel]

There are two other variables in the game. Front ride height affects camber angle. If too low, the camber angle would be negative. Moreover, if the difference between front and rear ride heights is different than the original setting, the castor angle will be accordingly different (less caster when the front sits lower). But this should not make the car handling bad.
Tony is right about driveshaft working angles...there is an instruction somewhere to lower the front ride height by 5mm on cars fitted with the later "tripod" inner joints. It seems that earlier 4-ball ones were capable of working in greater angles.
I have set the ride height on the Jogging (1108cc) to the 850cc figures on the front axle, and +20mm higher on the rear, and had it aligned on both axles afterwards. No weird angles or handling whatsoever, plus it looks like a R4 should (high!).