lowering ride height

All aspects of tuning,modification and repairs to the BX 16valve.
User avatar
Timmo
Full Throttle
Posts: 2236
Joined: Tue Jun 27, 2006 3:30 pm
Location: Cornwall! Tis where they make Oggy's!
Contact:

Post by Timmo » Sat Dec 19, 2009 9:34 am

a 15 mi;le back road blast is the longest mines been driven like it, if was nay distance used then was left in std mode,
Timmo 8)

After all i am the Cornish one!

Its Because its French!
Bx16v club - Sharing the love for the unloved!

surjit25
4000 rpm
Posts: 316
Joined: Thu Feb 07, 2008 3:16 pm
Location: Kuala Lumpur,Malaysia

Post by surjit25 » Mon Dec 21, 2009 2:47 am

If you lower the dshafts are going to vibrate like hell.
Then the frt struts gonna keep bottoming and they might be damaged internally.

User avatar
Timmo
Full Throttle
Posts: 2236
Joined: Tue Jun 27, 2006 3:30 pm
Location: Cornwall! Tis where they make Oggy's!
Contact:

Post by Timmo » Mon Dec 21, 2009 9:45 am

not nessecverily, its the same principle as lowering a normaly sprung car, as long as the shaft alignment isnt altered then the shafts shouldnt vibrate any more than normal! mine certainly dont when in lowered mode!
you'll only really bottom out the struts if you have it Very low and are Giving it some on a rough surface!
never had issues with either vibrating shafts or bottoming out on mine with it half way between the two notches.
Timmo 8)

After all i am the Cornish one!

Its Because its French!
Bx16v club - Sharing the love for the unloved!

User avatar
Simran
4000 rpm
Posts: 424
Joined: Sat Aug 12, 2006 12:30 am
Location: leicester

Post by Simran » Mon Dec 21, 2009 9:33 pm

I really cant understand why people think lowering the car with the lever is such a bad idea. The Height correctors are alot simpler than you think. It is literally a valve that when open, moves the other side until it closes - think toilet cistern, water level goes down, valve opens until level returns - valve closes. Citroen have 'cut' 4 slots in the gate for us to use that they think are adequate for road use, cutting more in wont harm the car in any way, what will harm the car is if you lower it and bottom the suspension out. If you choose a position that under normal driving never seems to bottom out, then continue enjoying your car. :)

Just to note, line pressures or any forces or strains on the system dont change by lowering your car by this method so dont be scared by it. Any problems that do arise are due to other issues such as not increasing the effective spring rate which you SHOULD do if you lower your car. Bad handling is due to a change in suspension geometry and bottoming out, the spheres are doing the exact same job they were doing before.

Whether you use the lever method or choose to rotate the clamp on the anti roll bar, you are effectively doing the same thing, fooling the car into thinking it is higher up than it is, so it keeps moving itself downwards until the valves in the height correctors close, voila lower ride height.

User avatar
docchevron1472
4000 rpm
Posts: 339
Joined: Tue Aug 22, 2006 10:53 am
Location: The End of the World
Contact:

Post by docchevron1472 » Wed Dec 23, 2009 1:52 am

Thats not strictley right actually.
The HC's are an active part of the suspension, there are damping discs in the HC's that do have an effect on the response rate of the suspension and there is a reason why the control rod doesn't contact the HC when the lever is set to normal ride height.

Citroen never intended the car to be driven at anything other than normal ride height, intermediate height is solely for giving extra clearance to get over large lumps or whatever, but they state (for good reason) that the car should be returned to normal height after clearing said obstacle.
Low and high are for service use only.
Whilst there's nowt wrong in lowering the ride height using the ARB clamp it's fundamentally bad practice to use the lever to attain those results.

As it goes the valver rides a tad lower than a diesel etc anyway, so there is scope for playing about with the ride height but to do that using the lever is bad practice.
1990 BX 16v Phase 2
1989 BX TD hybrid
1971 BL 350FG Ambulance (unique)
1993 Dennis Lance 132
That's when I reach for my Revolver

User avatar
Toddman
Administrator
Posts: 1334
Joined: Mon Jun 26, 2006 9:02 pm
Location: Lincolnshire
Contact:

yet again

Post by Toddman » Thu Dec 24, 2009 10:51 am

I welcome anyone to come and drive my valver to see what they think of the suspension.
Fact of the matter is if you lower the car using the height lever it will not handle as well as it should.
My car is lowered via the roll bar clamps to make the car lower to aid handling, and after lots of testing and consulting with time proven motorsport people ended up running the spheres that were mentioned earlier.

You can use the XM V6 spheres but they are really only suitable for track use as they are VERY harsh.

Simran when Chris had your valver he got me to sort him out the same spheres as I am running so unless you have replaced them you will be bale to lower your car with the lever without suffering the adverse affects you get with the standard spheres.

Cheers
Luke
Please call me Luke :)
1989 BX 16valve White 70k almost up to scratch

badlyworntoy
3000 rpm
Posts: 179
Joined: Tue Dec 08, 2009 5:43 pm
Location: middlesbrough

Post by badlyworntoy » Thu Dec 24, 2009 11:44 am

It seems that this has turned into quite a hot topic and knowbody seems to be able to agree?......simran you seem like a wise man,although im confused as to which way to go,could someone please sumerise as to the combination to use
ie.......Xm v6 sphere's front and rear or just front....bx valver front on rear or rear on front....etc etc
Extra notch in ride height lever or swivelling clamps???
which is it?
This is almost like a form of black magic

Also a daft question while im on.......Whats the science behind driveshafts vibrating when they point upwards and not downwards???ive always wanted to know this and knowbody ever seems to know
cheers

User avatar
Toddman
Administrator
Posts: 1334
Joined: Mon Jun 26, 2006 9:02 pm
Location: Lincolnshire
Contact:

spheres

Post by Toddman » Thu Dec 24, 2009 12:22 pm

Hi

My cars spec is here - http://www.bx16valve.co.uk/9.html

And I seriously doubt you will find a better combination of spheres for road and track use combined.

The guys who I worked with getting things right have been racing Citroens since the Ds days so know their stuff.
You can check out their website here - http://www.langworth-motorsport.com/

They don't do much general work these days but our family has been using them for a long time and one of the owners lives a few doors down from me.

I tried the V6 spheres and it was just silly,I also tried softer spheres from the 8v GTi and the rear of my car almost bottomed out when launching for a sprint.

Hope that helps

Cheers
Luke
Please call me Luke :)
1989 BX 16valve White 70k almost up to scratch

User avatar
Toddman
Administrator
Posts: 1334
Joined: Mon Jun 26, 2006 9:02 pm
Location: Lincolnshire
Contact:

theres more

Post by Toddman » Thu Dec 24, 2009 12:28 pm

I almost forgot!

Simrans car was running standard spheres that had been regassed with a lower pressure but Chris was not happy so decided to see what we could sort out, when Simran took on the car it was running the regassed to 35bar xm fronts on the BX rear and the old BX rears moved to the front so as I said unless Simran has changed them again you should be able to lower that car however you like without suffering the terrible bouncing you usually get when lowering a valver without changing the spheres.

Cheers
Luke
Please call me Luke :)
1989 BX 16valve White 70k almost up to scratch

surjit25
4000 rpm
Posts: 316
Joined: Thu Feb 07, 2008 3:16 pm
Location: Kuala Lumpur,Malaysia

Post by surjit25 » Thu Dec 24, 2009 3:54 pm

I have already tried this, if lowered 10-15mm it's ok,
m anymore like 25-30mm the driveshafts vibrate and the
front struts start to bottom and give a loud thud when hitting a pothole or speed bump.
In the long run this will not be good for the struts.
For extra firmness I have tried xantia hydractive spheres they are up to the
job but I changed them back later as I thought it's a Citroen
why stiffen the suspension, it should be a flying carpet ride.

Pete H
Posts: 8
Joined: Fri Jan 03, 2014 12:54 pm
Location: St Michel

Post by Pete H » Sun Jan 05, 2014 8:19 pm

Remember to smile!

User avatar
Timmo
Full Throttle
Posts: 2236
Joined: Tue Jun 27, 2006 3:30 pm
Location: Cornwall! Tis where they make Oggy's!
Contact:

Post by Timmo » Sun Jan 05, 2014 9:08 pm

Have you seen How jeth lowered his though?? Not the safest of lowering Methods! ;-)
Timmo 8)

After all i am the Cornish one!

Its Because its French!
Bx16v club - Sharing the love for the unloved!

Pete H
Posts: 8
Joined: Fri Jan 03, 2014 12:54 pm
Location: St Michel

Post by Pete H » Mon Jan 06, 2014 11:46 am

Sure, we know each other. :wink:
Remember to smile!

Mungous
Tick Over
Posts: 36
Joined: Mon Dec 30, 2013 12:32 am
Location: New Zealand

Post by Mungous » Mon Jan 13, 2014 9:50 am

Wow. That's... ...something else.

My car is lowered by about 40-50mm front and rear with no adverse effects from the driveshafts. It's not a daily driver though.

Harvey12
Posts: 5
Joined: Mon Mar 17, 2014 2:42 pm
Location: London

Post by Harvey12 » Fri Mar 28, 2014 4:29 pm

Pete, I am incredibly impressed. I did not think it was feasible to drop the car that low.

Not only a major engineering feat, but an artistic statement, too.

How well does it drive sitting that low? I assume you have to be exceedingly careful turning.

Post Reply