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The Adjustable Top Mount Fitment Thread

DavebGsi

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So First of all i'll explain this thread, basically after the whole fiasco of it taking ages to get the mounts etc, we want to make sure they are correct as far as we are concerned. when the mounts arrived, me Todd and Nige got mounts off kev to be the 'guinea pigs' as such, and to check everything is ok for everyone :)

So now we have had a chance to have a play with the mounts and fit them and came across a few things that need adjustment for a better fit, and general things to improve them!

obviously we would like to point out, once u receive your mounts, u can actually just chuck them on, they do fit and are usable, we just want to point out our thoughts, and of course.
We as a club are not responsible for the fitment, mods, or life of the mounts. this is just us covering our ass basically, After all, you all knew what u were ordering before you paid :lol: its all up to you what you do, to receive your mounts, simply contact kev and he will post them to you!

Right so lets begin!

Chamfer

so as a few of realised straight from the offset, the mounts being flat makes them different to the standard mount, standard mount is curved to allow for the shape of the body, where as these are flat.
The negative side of this is with the mount being flat is that only the outside edge of the mount will make contact with the body, this means more pressure on the edges due to uneven weight spread, and more likely to have flex in the mount, reducing the life.
As a result, we recommend gettin the mounts machined down or using a file to make a shape which matches the body of the vehicle.
The mount is made from 10mm aluminum, and this should be come 7mm at the outer edge, to give a chamfer identical to that of the body of the car.










Mount Improvements

So, a few things we felt could be improve on the mount! we first of all noticed if the mount is fitted as it came to us, the complete weight of the car, which is held in the middle of the mount of course is actually held with 4 small m5 bolts, which are only 10mm long, and are only held by thread, no securing nut or anything. Which decided this, although it obviously does work, is a bit more of a risk than needed! As you can see in this picture, the head of the bolts barely make contact with the mount aswell



There are two fixes for this me and nige worked out.

Fix 1

Cue the big washers and long bolts :thumb:



so the longer bolts allow big penny washers on the bottom, big contact area underneath, spreading the load right across the ally mount, and the nuts on the top clamp the bolts in basically, as a back up for the fact the bolt holes are threaded anyway. A worthwhile upgrade imo thou.



washer were sitting on the wonk a tad so needed a flat edge, the nuts on the top are not tall nuts to allow clearance, this allows them to fit perfectly in the flare of the body of the car!





these could do with being Dome Allen Key Bolts as they run effin close to the top cup, i can get a rag between the cup and bolts head so they do clear, but i have since bought new allen bolts to replace them with



bolts need to be m5/0.8 and 16mm in length with nuts, penny washers and normal washers
 
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Fix 2

The other way to fix the issue of the small bolts holding the weight of the mount if to flip the body of the mount the other way up and the middle part also. This has the advantage of not requiring new bolts, but does move the bearing down slightly, which will give u around a 5mm ride height increase, on top of any increase though fitting these mounts anyway.
We can't be 100% if the mounts themselves give an increase, or if this mod will either, or if it will even be noticeable, we haven't got that far yet and both me and nige run coilovers so can't tell. But this will allow another good improvement and this is how nige has fitted his mount.

its starts by instead of the mount being built like this.....




the mount is taken apart and the outside plate is flipped over.




Obviously ignore the chamfer being on the wrong side, its because my car is fix one obviously! u can see from the last picture how the ride height could be effected (if it is at all) and u can see how the plate is now nicely supported under the mount.

this means the centre disc of the mount is now underneath the outer body of the mount, and therefore weight of the vehicle is now support by the material of the mount, making the mount more secure, and the small m5 bolts now nolonger hold any weight, and only secure the caster adjustment instead.

Adjustment

For either of these fixes, the leg will have to be dropped slightly, if maybe compeletly to allow adjustment of the camber and caster. This is because of the nature of the bolts, being allen key bolts, you need to be sure you are on the bolt completely to avoid rounding off. this makes it a bit of a nightmare, but technically, should only need to be messed around with untill correct, then never touched again!

This section will be update once some measurement become available from people, please email me with details of yours setup and geometry measurements if you get these fitted with great success
The main advantage of these mounts are not only not having to replace them every few years like pattern part rubber mount, but also the adjustment avaliable.
This includes

Camber

Negative Camber is the angle of the wheel in relation to the road, the more negative camber you run, the further the top of the wheel leans in toward the body of the car. extreme camber will give you a 'sick' euro look (apparently it looks sick anyway), but will cause excessive tyre wear on the inner edges of your rubber. Cars Naturally gain negative camber with lowering, thanks to length between the top mount and ball joint becoming shorted through the shortening of the shock. This can be good, but can go too far. as a result these mounts can allow the setup you desire

Specs

Oem = 1degree 5minutes
fast Road = 2-2.5 degrees
Racecar = 4degrees

Caster

This is the angle of incline of the shock absorber, the correct caster is with the shock leaning backwards. Caster is used to create straight line stability in a vehicle by improving the strength of the 'steering wheel centring' This is pretty basic to explain. Basically a mk3 astra doesn't run hardly any caster, which is made worse by lowering the vehicle again.
To give you an example, oem spec of the astra is around 1.5 degrees of caster. A modern Car runs around 6/7 degrees!!!
so basically, the most cast that can be gained the better!

Factory spec = 2degress 15 minutes
lowered Car Before mount = 1degree 40minutes (ish)
Lowered Car After Mounts =

As a result, both me and Nige decided the best way to fit the mounts 'pre geo setup' if for maximum caster, with the mount lined up between the two mounting holes as per an oem mount. this will give a good ball park setup.





Of course, 4 wheel allignment is strongely suggested as soon as possibly to avoid tyre wear and handling issues
 
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Top Nut

Finally, due to the added 'fatness' of the top mount compared to oem, it uses up another 10mm of the thread at the top of the shock which the top nut requires.
as a result, not much thread is left to secure the shock assy. As u can see i can only just get this very flat nut on the top. and when fitted with the top mount spacers, the nut barely goes on




Top mount bearing washers

Pretty simple really, these are wrong :lol:. they are m14 where as the oem astra shock, and aftermarket shocks, are m12!

Double Fix

as a result a double fix, Both bottom spacer and top nut, can be bought either from compbrake.....



however the top nuts needs cutting down as it is too tall....



or, Nige is actually in talks with a company who should be able to produce these for us, thread will be updated soon. an answer should be around next week (13th-19th April 15)

we will let you know!

Fitting

Fitting of the mounts is very simple....

Spring
Top Spring Cup
Oem Bearing (needed if running coilovers or not)
Bottom Spacer
Top Mount
Top Nut/Spacer
 
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Just wanted to ask, when you have them set for max castor, how much clearance is there between the steering arm and the hole the arm comes through ?
 
I've had Escort Cosworth top mounts on mine, I got them re drilled and they fitted fine. I think you can only do so much with the handling on these cars, but hey ho.
 
Have anyone had any issues with steering arm and steering rack interference with increased caster angle?
When i looked my car, clearance between arm and rack on left side (LHD car) was very small when wheels are straight.

Is there any new info about the availability of these mounts?

Cheers from Finland!

-Ville
 
Have anyone had any issues with steering arm and steering rack interference with increased caster angle?
When i looked my car, clearance between arm and rack on left side (LHD car) was very small when wheels are straight.

Is there any new info about the availability of these mounts?

Cheers from Finland!

-Ville
A chap in Italy has had no issues with his car at all, he was the first to have a set of these
 
Hi

I'm locking for it

Do you know, where I can buy it?

thanks
 
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Hi

I'm locking for it

Do you know, where I can buy it?

thanks

You cant.

These got made as a one off but I am looking to get more made if you want to be added to the list?
 
You cant.

These got made as a one off but I am looking to get more made if you want to be added to the list?

I may be interested in a set, keep us posted :)
 
Better design, well same but issues sorted
 
I've been thinking of getting a set made but with a polyurethane bush in it so it's not just solid, trying to work it with using a standard powerflex bush or something like that
 
I'm a bit curious how 4 small bolts can stop the force being placed on the suspension.`A few rough knocks and i feel like those bolts would start to shift.
 
I'm a bit curious how 4 small bolts can stop the force being placed on the suspension.`A few rough knocks and i feel like those bolts would start to shift.

which 4?

ive now done a full day track day and serveral thousand miles on the road and check them for cracks when i wash my car and still all good :), i think their stronger than we think
 
I have camber plates with uniball bearing. Do I need need orginal bearing under it also?
 
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New version available from compbrake which is straight fit and better design.
 

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