Board logo

MNR Inboard Ride Height
bassett - 13/12/09 at 03:04 PM

Hi, Marc sent down my new push rods(34cm over the 36cm) and ive just fitted them. I am aiming for parralel wishbones to the floor as a starting setup following from what ive read. I am curious how owners have acheived the correct height ie have you just changed the height by raising the spring collar up/down or collar and twisted the push rod to increase/decrease its length. If yours is similar to my spec and been pro setup what have you found to be best? I know it will be much trial and error but a good base point will help.
Cheers
Adam


mr henderson - 13/12/09 at 05:07 PM

Any chance of a picture?


A1 - 13/12/09 at 05:19 PM

screw the rosejoints in/out the end of the pushrods
if you screw the spring collar up and down it plays merry hell with the ride, just take up the slack on the spring


bassett - 13/12/09 at 07:54 PM

i would normal get a pic but it wouldnt really show an awful lot. how much would you say slack is when tightening the colar - just when easy movement stops? i had noticed before when we went over this point the car is skitish on bumpy fast road but that might just be overly weighted spring


Johneturbo - 13/12/09 at 08:01 PM

I've got my push rods as short as posible and about, 12/15 threads showing on my shocks counting from the bottom up.

for corner weighting you would adjust each rod to get it optimum

[Edited on 13/12/09 by Johneturbo]


mr henderson - 13/12/09 at 08:11 PM

quote:
Originally posted by bassett
i would normal get a pic but it wouldnt really show an awful lot. how much would you say slack is when tightening the colar - just when easy movement stops? i had noticed before when we went over this point the car is skitish on bumpy fast road but that might just be overly weighted spring


Overly weighted? Do you mean the spring is too stiff? How about a sketch?


Gergely - 13/12/09 at 08:40 PM

Marc told us to first set the damper travel - 2/3 of the travel for bump and 1/3 for droop (or how you call it) when resting on a level ground. You set this with the sprong collars. Once done, you adjust the pushrods to ensure that the lower wishbone is parallel to the ground. I our case this meant tha shortest possible pushrod setting and even then it was a little higher than it was supposed to be. But after the first hundred miles it sort of settled in and now it is fine.
I hope this helps...
Gergely


bassett - 13/12/09 at 09:06 PM

MNR owners - thats interesting as mine is currently set at 16 threads from bottom on the coilies(done up as tight as possible by hand with no weight on them) and with the new shorter push rod at there shortest its about 1.5cm to low so i will drop the shocks to just take up free play then adjust the push rods out but this sounds like my push rods are really short in comparison to you guys? If you have a free moment any chance you could let me know the length of yours as maybe im better off with the originals which i thought were designed for if the pushrod mount was on the bottom of the wishbone.

mr hendson - i remember reading another MNR owners comments that when he changed from the stock springs(175lb) down to 150lb he noticed a more compliant ride on fast bumpy road which i think is similar to mine as i am more confident going fast on these particular roads in my Leon.

Thanks
Adam


Johneturbo - 13/12/09 at 09:22 PM

I'm tepmted to drop down to a lower poundage from 175- to possibly 150 or lower.

i think with the inboard set up you have a ratio from the pushrod/rocker to spring.

sometimes i feel like i'm suffering from bump steer.


Smartripper - 13/12/09 at 09:37 PM

Hello

I've made te chance from 175 to 150 end i can tell its way better on bumpy roads..

So much nicer to drive then.

Greetings Daniel


bassett - 13/12/09 at 10:01 PM

Hi Daniel, i dont suppose youve had it on track before and after the change and if you dont mind me asking how much are the springs and are they just front or all 4?
One day soon mine will make it to brands and hopefully some others so i really wouldnt want to compromise the setting when i have a fast road car at home and this as the track toy if that makes sense.
Cheers
Adam


mr henderson - 13/12/09 at 10:04 PM

If it's mainly for track use you may want to keep it stiff to resist roll. Softer springs will usually be better on bumpy (normal!) roads, but on a smooth track at high cornering force then resisting roll will be the main priority.


Smartripper - 13/12/09 at 10:24 PM

hello,

Not on track sorry,

spring were only front i think 30 pounds.

but on fast roads car still feels stiff, or set damping stiffer...

Daniel


spdpug98 - 14/12/09 at 09:32 AM

Hi Adam

Not sure if this is any help, but my shocks have about 5/6 threads showing and my pushrods have about 2/3 threads showing top & bottom

I have not had my set up professionally, but did do it myself with a fellow racer (so could probably be improved!!).

I found that at higher speeds on bumpy roads, the car was very very skittish, that was with the shocks all set at the softest setting. I then started upping the rate until I was happy with the settings, I now have about +9 (clicks) on the rears and about +8 on the fronts and the car is a lot more stable than before

Not been on track yet but it is much improved on the bumpy back roads

Dave


bassett - 14/12/09 at 01:48 PM

Cheers guys, i think il keep the springs for the one eventual day it makes it to the track just so it as uncompromised as possible. Dave thats interesting as i think if i had my springs that low the push rods would have to go a lot further. Is 5/6 turns on the coil before the point where the slack is taken up? and are you running upturned wishbones(mount on top) with shorter rods?
Thanks again
Adam


spdpug98 - 14/12/09 at 03:30 PM

quote:
Originally posted by bassett
Cheers guys, i think il keep the springs for the one eventual day it makes it to the track just so it as uncompromised as possible. Dave thats interesting as i think if i had my springs that low the push rods would have to go a lot further. Is 5/6 turns on the coil before the point where the slack is taken up? and are you running upturned wishbones(mount on top) with shorter rods?
Thanks again
Adam


Adam

Not sure if these pics help, I run my wishbones with the mount underneath:






Gergely - 14/12/09 at 04:22 PM

As said again, just make sure that you have enough travel in the dampers, otherwise they will bottom out on the bumpstops and you will bend your wishbones like we have...
This is why Marc recommended the 2/3-1/3 rule for damper setup, then adjust the pushrods for correct ride height. From spudbug's pictures it seems to me the spring cpollars could be quite low and may bottom out - but can't really see from the photos... anyway, just watch your setup...
Just my 2p's worth...
Gergely


Frosty - 14/12/09 at 05:45 PM

Adam on a setup note, go slightly higher than parallel wishbones to give you ideal camber control. It's also very important to set the ride height with the target weight in the car (I.e. with you, or you + passenger on board with fuel).

If you start with parallel you may find that you have to run more camber than you need to. The reason being is that as soon as you corner, the loaded wishbone will go beyond parallel, and you will have lost camber, so you would have to run more camber than you need due to the fact you will lose a given % of it as you corner.

If however you set just above parallel, you can run less camber than you need, because you will gain it naturally as you corner (opposite effect).

How high or low you set the spring platforms will depend on how much bump travel the car is likely to see, which depends on a few things like spring rate and weight etc.

I would set the spring platforms about half way (same both sides), and then adjust the rods. This will give you suitable travel for bump and droop.

The general rule of thumb on the rose joints as to make sure you use at least 1.5 x the width of the thread. Any less and you could be in trouble.


bassett - 14/12/09 at 07:21 PM

Dave ours will definitely be slightly different then as ours mount to the top as i thought that was part of the safety notice regarding the circlip. i think i will try and set the spring heigh as Gergely recommends.

That is a very good point Frosty I had
been looking at the ride height completely from a static view and we generally drive 2 up and i imagine our first few track endeavours will be the same.

Wont be a problem with the rose joints though the threaded portions are about 6-8cms long either end.
Thanks for everyones input
Adam


spdpug98 - 15/12/09 at 09:00 AM

I know that MNR read these threads so it would be good if MNR could give us all some feedback, as it appears we all have different set-ups but all seem to have the same (similar) parts

I am now concerned about my set up as it does seem I have very little damping and am concerned about hitting the bump stops, but saying that it may be OK as I have a seen a couple with only a few threads on the shock showing


spdpug98 - 15/12/09 at 09:00 AM

I know that MNR read these threads so it would be good if MNR could give us all some feedback, as it appears we all have different set-ups but all seem to have the same (similar) parts

I am now concerned about my set up as it does seem I have very little damping and am concerned about hitting the bump stops, but saying that it may be OK as I have a seen a couple with only a few threads on the shock showing


procomp - 15/12/09 at 09:21 AM

Hi

Is it not also a case of the bottom damper mounts are totally different on some. Some of the ones i have seen have a 2"-3" spacing and some couldn't even be fitted without machining the bottom eye of the dampers.

Cheers Matt


marc n - 15/12/09 at 04:42 PM

hi all
not getting on here much due to ridiculas workloads, i just dont have time to surf the net these days, best bet any querie is to email us not rely on me looking on here, there is someone to help all technical questions available on email 9 am - 5pm monday to friday and 9 am till 1pm saturday, all emails should be answered within 2hrs where possible.

to the question :- would need an email with chassis number to answer, but a rough guide is narrow shock spacing early cars wide shock spacing later cars so if you specify chassis no. , suspension type then we can help

cheers

marc


spdpug98 - 15/12/09 at 05:13 PM

quote:
Originally posted by marc n
hi all
not getting on here much due to ridiculas workloads, i just dont have time to surf the net these days, best bet any querie is to email us not rely on me looking on here, there is someone to help all technical questions available on email 9 am - 5pm monday to friday and 9 am till 1pm saturday, all emails should be answered within 2hrs where possible.

to the question :- would need an email with chassis number to answer, but a rough guide is narrow shock spacing early cars wide shock spacing later cars so if you specify chassis no. , suspension type then we can help

cheers

marc


Thanks, sent you an email


Johneturbo - 18/12/09 at 04:04 PM

Spdpug98 what settings did you get? as i think we have the same chassis/set up


spdpug98 - 18/12/09 at 04:09 PM

quote:
Originally posted by Johneturbo
Spdpug98 what settings did you get? as i think we have the same chassis/set up


Marc has told me I need to raise the shocks/springs approx. 10mm, but I have no adjustment left on the pushrods to compensate for the change in shock length - so waiting for some more information / ideas from Marc

Will keep you updated

[Edited on 18/12/09 by spdpug98]


Johneturbo - 18/12/09 at 04:24 PM

IF you raise the spring platforms you would need to shorten the pushrods to compensate


mr henderson - 18/12/09 at 04:27 PM

Sounds like the springs are the wrong length.