Steering Suspension Mod for Supastox

[Bosscat]

Have seen a couple of references to a mod to the front on SupaStox also referred to as Mi5 mod.
Can anyone one tell what it is and is worth it???

[SlowOne]

It refers to the replacement of the grommets in the front beam with swivel joints from the Mi5 Touring car. This gives the car much greater steering precision all round as well as making the whole assembly simpler and lighter.

You need a couple of these (http://www.racing-cars.com/pp/New_Ca...Mi5/U4244.html) from Schumacher. Take the grommets out. The ball and socket assembly is a direct fit in the hole. Fit with the flange side down when the beam is put back on the car. When fitted, run a very small amount of superglue around the plastic socket where it meets the carbon beam. This is just a mans of stopping them falling out if you have the assembly apart - they can't fall out on their own. That's it.

My set-up is to have both carbon spacers under the beam, and then the bolts go through that and thread into the balls. Do the bolts up then nip them to clamp them in place. Don't over tighten. If you are worried, put a nut on top of the ball for safety - I don't bother.

Now set the ride height by putting spacers under the spring as in the kit instructions. You are aiming for 6 deg castor when the car is off the ground. Depending on your tyre sizes, adjust the height of the front of the beam and the rear using spacers so you have at least 4mm ground clearance and 6 deg castor.

Now set the car up ready to race with everything fitted. Adjust the front springs so it has about 0.5 to 1mm of 'droop' in the suspension and then about 4 to 5 deg castor. Make sure the spring pressure is equal on both sides. Set the ground clearance to 3.5 to 4mm.

Now set the rear ride height to 4mm minimum and again set the 'droop' to about 0.5mm to 1mm. The chassis should be level - same ride height front and rear.

Don't set the ride height to what you want on the track. The bodies weigh 80 to 100 grammes, so when fitted the car will drop about 0.5mm. Fit the body and confirm you have 3.5mm minimum ride height both ends - chassis level. Use 4mm if your track is bumpy.

I think it is well worth it. My car went from being a bit random on occasions entering bends to being as tight as a 12th car. £4 plus 0.005p-worth of glue and an hour or so to fit it all and I have a lighter and more accurate car. What's not to like! HTH

[BD5]

I run a o-ring on top of the front beam/mi5 pivots as per the standard kit but keep finding the nut comes loose somehow and the has ruined 2 meets for me now!
Don't you adjust ride height with the nuts on top of the springs? Surely does the same job as the spacers?

[SlowOne]

BD5 - if you run Orings on top of the pivots then you need long bolts and use the nylok M3 nuts that you took off when you replaced the grommets with the Mi5 pivots. Ordinary nuts will come undone, a good nylok nut will not. If the nylon insert in the nut has worn, fit a new nylok nut.

Yes you can adjust the ride height with the nuts on the springs, but that will change the static castor. If you have too much castor the car tends to hook on corner exit, and too little makes it twitchy on corner entry. Also, if you only use the nuts on the springs, then the droop in the front suspension changes, which changes the weight transfer, which changes the handling. Too much droop and the car will understeer under power.

As described above, balance the ride height with the static castor angle by fitting spacers under the front beam and under the springs until you have a 6 deg static castor with the chassis unloaded. With the car loaded for racing, you should have 3.5mm ride height and 0.5mm to 1mm droop. The final ride height adjustment can now be done on the front springs. 0.5mm change in droop has little effect on the handling, and accommodates a 1mm difference in tyre diameter to maintain your chosen ride height. HTH

[mark christopher]

If you join the Facebook group 12gt circuit uk there is a helpful Supastox guide in this files one of our members has done. I'll post a link in a min

[mark christopher]

page
https://www.facebook.com/groups/336445139755237/

set up sheet

https://www.facebook.com/download/21...%26%20Mods.pdf

[BD5]

Thanks for the info slowone, what method/tool do you use to measure the static caster on a supastox?

[SlowOne]

I use an RPM camber gauge like this one...

http://www.rpmrcproducts.com/product...ges.htm#Camber

Schumacher also do a rather fancy one that might be easier to get...

http://www.racing-cars.com/pp/Produc...ist/H1032.html

I don't know where you buy RPM stuff in the UK. I have had my RPM gauge for a long, long time and it is still as good and as useful as ever! HTH

[mark christopher]

Cml do rpm

[SlowOne]

Thanks, Mark. Here it is...

http://www.cmldistribution.co.uk/cml...tId=0000007717

...so get your LHS to order it and for less than a tenner you have a tool for life. What's not to like??!!

[BD5]

thanks, i figured a manual camber gauge which i had in my box, 4mm ride height, 6 degree static camber,1mm droop f&r and i didn't have to put spacers under the springs which was a result. If i wanted to reduce the droop to 0.5mm how would i achieve this?

[RC Kev]

I just updated the setup guide with some excellent info from above

https://www.facebook.com/download/pr...58651264251501

Kev

[SlowOne]

If you want to reduce droop by just 0.5mm, do it on the springs. Just wind the nuts up or down a couple of flats until you get what you want. The car doesn't seem that sensitive to such small changes to static camber angle for my driving ability - 0.5mm is not a lot in the grand scheme of things! Watch the ride height when you do that.

The alternative is to slip an 0.5mm washer under the front or rear 'beams' to increase the height of the down stop 0.5mm. If you can get plastic washers, you make a single cut from inside to outside and then clip them over the screw - saves you having all the hassle of taking it all apart just to get a spacer in.

The spacer option is best as it means that your ride-height is unaffected. If you need to change ride height you can clip the washer off, or clip another one on. I have a range of old 12th spacers (actually 0.030" as they are originally imperial thicknesses) that slip over the screws, but don't fall off as there is no side load on them.

Please don't forget that ride height and droop must be checked with the body on because GT12 bodies weigh so much. once you know how much effect the body has on your setting with the rolling chassis, you can allow for that. In my case, I use 3.8mm on the front and 4mm on the rear. When the body is on, both ends are 3.5mm ground clearance. Front droop is therefore 0.8mm to 1mm, and rear about 1mm to 1.5mm with the body off. The difference is because the rear springs on mine (yellow) are much softer than the front springs (red or blue for me). With the body on both ends are between 0.5 and 1mm droop and again, I can't tell any difference on the track.

Play with the droop as it affects weight transfer and you may prefer the car's handling with more weight transfer (more droop) at one or both ends.

I don't do FacelessBook, so if anyone has any questions from there please post them here and I'll answer them. HTH

[Bosscat]

Ok so many thanks for all the replies to my original question much appreciated.
At the risk of asking a silly question how do you use a camber gauge to check static caster?

[mark christopher]

Originally Posted by Bosscat

Ok so many thanks for all the replies to my original question much appreciated.
At the risk of asking a silly question how do you use a camber gauge to check static caster?

remove wheels
chassis on flat surface side ways on to you
line edge of king pin with edge of camber gauge take reading of camber gauge

[Bosscat]

Thanks!!!