Quick Question Needs Answering

[Rally Slag 0]

i've done a search but didnt find the answer, once i've finished rebuilding the rear beam on my 309 i need to set it up of the car to save time when fitting it, i got these measurements from the rear beam rebuild guide on the home page:

- Models with engines XV, XW and XY7: 340.0mm

- Models with engines XY8: 336.0mm

- Models with engines XU5J and XU9J: 330.5mm

now are these measurements for a 205 or 309 or both because the guy who wrote the article used a 309 beam but on a 205 so im a bit confused. also he states this: A change in the dimension between shock mounting bolt centres of 2.0mm is equivalent to a change in ride height of 3.0mm, again is this for a 205 or 309. Someone please give me an acurate answer,

cheers

[Baz 421]

Both. The 205 and 309 Gti's have XU series engines. 330.5mm.

[welshpug 1,657]

same applies to the 306/zx/xsara trailing arm as well.

 

so if you want your rear end 30mm lower set the distance between shock bolt centres to 310mm, thats if your car is XU5/9J.

[jonah 1]

- Models with engines XU5J and XU9J: 330.5mm

That's the figure out of the Haynes manual for a 205, but it's not accurate in my experience. I found that on my 1.6GTI, 322mm gave the correct ride height (the Haynes manual also gives a figure for this and shows where to measure it).

 

Also I certainly wouldn't assume that figure is true for other cars (309 etc.)...

 

A change in the dimension between shock mounting bolt centres of 2.0mm is equivalent to a change in ride height of 3.0mm, again is this for a 205 or 309.

That also comes from the Haynes manual, but is wrong. It should be 1.0mm for 3.0mm change of ride height. And that does apply to both 205 and 309.

Edited June 20, 2007 by jonah

[dani959 0]

That also comes from the Haynes manual, but is wrong. It should be 1.0mm for 3.0mm change of ride height. And that does apply to both 205 and 309.

 

Just bear in mind you won't be able to get a 1.0mm difference on the arm. The minimum you can lower/rise is one spline, which makes the 330.5 an approximate dimension. I could almost bet that you'll get the same height on 329, 330 or 331 mm.

[Super Josh 4]

The minimum you can lower/rise is one spline

 

That isn't correct. Due to the fact that the splines on each end of the Torsion Bars are offset from each other, you get a vernier effect. So you can set the gap at almost any distance and then rotate the Torsion Bar until is slides in nicely (Oooh Err)

 

 

 

Josh

[Richie-Van-GTi 71 2 Cars]

yup, as Josh says, if you want to lower an exact amount simply withdraw the torsion bar completely leaving the trailing arm secure on the ARB and tube, position to the required drop by measuring shock length or distance from wheel centre to a fixed point on the arch then re insert torsion bar slowly rotating it until it just slides into position.

[Rally Slag 0]

now im more confused lol, who is right and whos wrong, i have the beam stripped completly, everything has been cleaned and repainted, the torsion bars are fully removed and now slide in an out with ease. i no the splines are different both and so you can adjust the right hide pretty much in milimeters.

 

But is this right: It should be 1.0mm for 3.0mm change of ride height or is it 2.0mm for a 3.0mm change of ride heights.

 

So i need to go have a look in a haynes manual for a 309 to get the correct ride hieght or not because one person just said its same as 205 and one just said it wasnt. I didnt think the haynes manual coverd torsion bar beams and ride height, the one fo rthe citroen ax doesnt, i know that much.

[welshpug 1,657]

the ax doesnt cover beams as its a service and repair not workshop manual

 

my haynes for a 309 doesnt have much information on the different models ride heights, only that the ride height should be between 436 and 450 mm, and that the shock bolt centres should be set at 347.5mm when the torsion bar is fitted.

 

a dummy shock absorber is a godsend when fitting torsion bars, and theyre a doddle to make if you can weld as all you need is some steel pipe of appropriate diameter and some threaded rod and nuts.

[jonah 1]

I didn't say it wasn't the same, just that you can't assume it is. Anyway we now have a figure for a 309 of 347.5mm (for which model though?), which is different to all of the 205 figures above.

 

I would just make a rough guess and assemble the beam, then measure the ride height of the car adjust the beam if necessary. It's easy when the torsion bar splines aren't seized into their housings.

 

The ride height to shock length ratio: the value of 3:2 in the Haynes Manual must be just a typo. The Peugeot Sport rallycar build book says it is 3:1, and I measured the angles and lengths of a trailing arm, did a few calcs and also got a figure of almost exactly 3:1. I really am certain that this is right.

 

BTW it's only the older editions of the 205 Haynes manual that cover the rear beam in detail (and gearbox internals!).

[Rally Slag 0]

yeah i plan on making some sort of dummy shock but thats why i wanted the correct measurment. I bought a 309 haynes manual and peugeot workshop manual of ebay last night so when they arrive i'll have another read but the figure you gave sounds about right for some reason, cant work out why it does though lol. Just gota decide how much i want to drop the rear of the car by, i fitted 30mm eibach front springs but never botherd to check what i actualy dropped by so will have a check of that then can set the rear to match. Thanks for the help guys, once i've sorted my beam im gona put a post on the 309 forum and on here with all the peugeot part numbers (because i bought everything new except the beam tube, torsion bars and trainling arms, i did replace the shafts) so that we have a correct reference for future experiences.