What length for dummy shock when lowering rear?

[simonh]

Sorry if this has been covered before but I seem to have my theory wrong.

I saw from a couple of guides etc that the standard height is a 330mm length, somewhere else said that 322mm gave a 25mm drop and I saw 320mm gave a 30mm drop. This would suggest that for every 1mm shortening of the dummy damper the ride height will drop somewhere between 2.5-3mm (as a rough guide)

Based on this I made the dummy shock 315mm centre to centre and expected a drop somewhere between 37.5mm and 45mm but the car seems to have dropped much further with the Cyclones rubbing the rear inner plastic arch before it's even been driven and settled. Most of the tyre is inside the arch which looks good but doesn't match with my 'practical daily' theme and 40mm drop at the front.

Does anyone know the exact correlation between damper length and ride height? Is it the same for the Sedan and the hatch?

Thanks a lot.

[Jonny81191]

Say whaa?

Lowering the rear by shortening the shocks is not how people normally do it

Might wanna go and do your research again. Look at lowering by adjusting the torsion bars

[1616six]

Am I reading this right, have you made a 'dummy' damper, to pull the beam closer to the car to lower it?!

[Connor]

No you guise... The dummy shock is for when the torsion bars are out, you set the distance between shock mounts and then slot the torsion bars back in, that way you'll know you have both sides exactly the same. Sadly I have no idea what distance equals what drop

[Jonny81191]

Oh.. Facepalm

Just measure between the hub centre and the arch, then yo can set the distance exactly as you want it

[simonh]

I'm too new to know whether most of these replies are sarcasm or confusion. Guess I didn't give enough background info for the story!

Will just set it using the jack and tape measure I think! From what I read it was advisable to use the dummy damper method to ensure that the drop was even at both sides.

[Jonny81191]

I'm too new to know whether most of these replies are sarcasm or confusion. Guess I didn't give enough background info for the story!

Will just set it using the jack and tape measure I think! From what I read it was advisable to use the dummy damper method to ensure that the drop was even at both sides.

You'd confused me!

I see what you mean now though

[Grant]

I'm too new to know whether most of these replies are sarcasm or confusion. Guess I didn't give enough background info for the story!

Will just set it using the jack and tape measure I think! From what I read it was advisable to use the dummy damper method to ensure that the drop was even at both sides.

Take everything on here with a pinch of salt bud!

I don't know what the shock length would equal, but if you measure your arch, then put a shock in, I'm sure a lot of people would be very grateful to have that information. It would be very useful to have

I've only ever lowered with measuring to the arch from the hub, and never had any problems

[Connor]

I'm too new to know whether most of these replies are sarcasm or confusion. Guess I didn't give enough background info for the story!

Will just set it using the jack and tape measure I think! From what I read it was advisable to use the dummy damper method to ensure that the drop was even at both sides.

No you provide enough information and they weren't taking the piss, just being stupid and arch to hub can be inaccurate as the arches might be slightly different

[Grant]

No you provide enough information and they weren't taking the piss, just being stupid and arch to hub can be inaccurate as the arches might be slightly different

I've never encountered this. The only way I think that would happen is damage/rolling, no?

[Niall]

Measuring arch to hub is accurate enough if your careful with the tape. It will never be millimetre perfect but it will be good enough to not be a noticeable difference. The dummy shock method is good but not really needed for us! lol

[Grant]

Measuring arch to hub is accurate enough if your careful with the tape. It will never be millimetre perfect but it will be good enough to not be a noticeable difference. The dummy shock method is good but not really needed for us! lol

Exactly what I was thinking.

TBH though baker and other people sell dummy shocks for £15 a set at shows. If you intend to be doing it more than once, seems a fair enough investment to me

[simonh]

Tape measure was the answer. Pretty happy with the way the car sits now. Think my beam's probably knackered though as with the bars out there's practically no resistance to hold the trailing arms. They just slide in and out. Guessing this isn't normal? Camber doesn't look too bad but this was allegedly a reconditioned beam last year and I've been working on it for a few nights now and still haven't found any reconditioned looking bits!

[Grant]

How easy did the torsion bars come out? Was there any sign of copper slip grease anywhere?

[simonh]

Had to soak them for days to even dig out the washers. No copper slip or grease anywhere, just muck and rust. The beam to body mounts look new but that's it. Guessing it's just been a second hand one. Some silicone sealer inside one end of the anti roll bar plates but even that didn't look very fresh.

[Grant]

How were the bars coming out? Easy or a pain in the arse?

Doesn't sound too re-furbished so far

[simonh]

Passenger side one not bad after i adapted the slide hammer attachment to get a direct pull. Drivers side a complete pain in the arse, especially the trailing arm end.

[strictly_perv]

The way I do it it to put a jack under the hub, remove bars, measures the distance between hub and arch directly above, wind jack up to desired drop and put bars back in. Done.
Just remember to push the trailing arm down as far as it will go before you put the jack under the hub.