CAT SX Build Tips
 

Thought I would just start this thread for information and tips when building the CAT SX.

Firstly I would recommend looking at the set up sheets in the back of the manual before building the car. Unfortunately the manual was designed well before a lot of the development work was done so does not necessarily reflect how the guys have run it.

Secondly and quite importantly there are some features/settings on the car that can run you into trouble with the diff outputs both front and rear.

It is possible if the car is run with a combination of some of the following it is possible to snap the diff outputs if they drop into the output slot under full bump; (as shown in the picture below)

-Very narrow (Small amount of washers against transmission)
-Very laydown shock
-Short upper camber link
-Very short shocks

To check, hold the suspension at full bump with shock attached and make sure the driveshaft rotates smoothly and clears the slot.


http://www.racing-cars.com/images/sx_outputs.jpg

I for one will be running an O ring above the spring retainer for a bit of extra impact absorption.

What a great idea.

Would be nice to see plenty of tips on here.:thumbsup:

Great tips!!
 

Thanks for the tips... Keep them coming...

I can recommend checking the plastic belt pully guides for sharp edges as mine have some nasty ones which could catch the belt.

well soon as i drag myself away from Ibiza i will start to build mine :thumbsup:

Well I have built the shocks and put all of the rest of the car together today and have the following notes and advice:-

There does seem to be alot of slop in the steering and the plastic ball cups do seem to be very slack on the balls. Whether this is a problem will only be found when the car is run.

When screwing the threaded pivot pin screws through the hub carrier into the yoke make sure the you get it as square as possible otherwise the yoke wil be stiff when rotating. Mine wen slightly out on one side and I made sure I was much more careful on the otherside.

Clean the inside of the shock bodies top and bottom and make sure that the o-rings and plastics that go in the end of the shocks are clean of any of the white power.

Put some shock oil on the threads really helps the parts go together avoiding getting anything cross threaded

I feel that the 25wt oil in the front shocks feels very light. I like the feel of the 35wt in the back. I suppose I will find out how it goes when I run the car.

Make sure that you do not follow the dimple holes in the undertray and actually measure this up and make the holes based on where the tray ends up sitting.

The setup provided by following the manual gives too much camber change front and rear. I recommend refering to a setup sheet in the back, or on here, to decide on a position - but don't start on that manual setup guys. Same goes for shock oils/pistons/position.

Also, I am sure Matt White will confirm or correct me, but where the manual setup states 0mm for the front outer ballstud height, this is when the caster block has been cut so the top is level.

Also, as mentioned, put an external spacer on the shocks. I have put 3mm in all mine tonight to begin with which is verging on excessively big (until I get some more Nortech O rings at weekend), and combined with a sensible camber link setup, the driveshafts miss the slots by miles now. O rings here are better than solid spacers, each O ring as an average compresses to 0.03', so I will be putting 2 on per shock. if your driveshaft goes into (or very close to) the slot of the outdrive at full compression - reduce driveshaft plunge further (either with camber change or car width) or limit shocks more.

Chris has a point - certainly my setups (including the one in the manual) will always be with the front caster block "flattened".

So without any longer turn buckles etc, how should the camber be set on each corner to avoid the driveshafts catching the outdrives?
Say if you only have the basic stuff and no fancy bits.
Because I've noticed that Simon runs longer links compared to Matt, do you need longer turnbckles for this or do the kit ones stretch?

What length should the camber links be? etc.

On the front, the turnbuckles are long enough. But on the rear they are only really long enough to meet the middle hole on the hub - any longer and you need a longer turnbuckle.

There is another way of helping the driveshaft miss the slot, go to a high diff. On the rear I want to keep some camber change, so I have gone to 4mm stud, middle hole, high diff.

On the front, I have gone to 1mm ballstud, 0mm on castor block (thats cut level).

Going by the setup sheets its around about what the guys have been running. No doubt I will try and change it as its still early days, but I won't self-destruct outdrives like this. :thumbsup:

Myself, Sharpy and Ben have been runnng cars with long rear turnbuckles and narrow upper camber mount, also the front narrow inner camber mount.

The car runs better softer - i started off trying to turn mine into a B44 but it just does not work, Keep The Oils Soft !

Everyone will have to find a setup that suit them but im glad to discuss mine with anyone at Worksop :)

Any of you guys actually 'seal' the edges of all the carbon bits n chassis, using super glue?

Lol, nah, I was too excited and had to build it! :lol:
Maybe will do my spare parts, and I need to kill some time, nowt on TV etc.

Cheers dudes,
Does it run better with the longer links then?

Good point Tel....

It would be nice to see a good base indoor starting set, using kit parts.
As from my point of view, my set-up will consist of Mossy's starting set-up as far as kit only parts are concerned, until i get hold of some of the option parts.

Over time, this will come. :thumbsup: Its a new car at the moment but now many people are learning and eventually the ideas will pool, carmaggedon!

This is one of the reasons i'm looking forward to running this car so much :thumbsup:

Regarding rear camber links, I changed this with advice from Chris Long and Si Moss as my SX seemed to be very short of traction at the rear. I used a shorter carbon mount and the longest setting on hubs but what i did find is that the purple schumacher turnbuckles that i got on the day(Mr Schumacher himself said they were correct) were not quite up to the original quality and seemed very loose when installed. I could change camber by using my finger and thumb. The bal cups were on enough but just didnt seem like they had a deep enough thread on. I noticed most running this option had the old Lunsford turnbuckles that seemed thicker.
This option gave me so much more rear traction and made the car so much easier to drive. So much more to learn. Excellent car!

Just for you guys, I only made a few minor changes to the setup i previously posted for Worksop over the day. Here they are -

Changed Front Diff to One Way (make the car pivot through the hair pins and carry more speed through the sweeper)
Added 1mm under the front ball stud, now running 3mm (more mid corner steering)
Dropped one spring rate all round Front = Grey > Red, Rear Red > Yellow

Car felt pretty dialled all day so this is the setup i will be starting with next time. Any questions let me know.

Si

Well looking at that, it looks as though I went the right way with my setup.:thumbsup:

Just need to buy some new eyes!!:lol:

hi sorry to be a little dumb but what do you mean by cutting the castor blocks flat?

do you mean cut off around 3mm?:eh?:

and is this done to reduce camber angle movement/travel?

or am i paddling up the wrong stream:eh?:

thanks Phil:thumbsup:

Where the camber link connects to the hub, it steps up under the ball joint. This is being chopped off so that that area is flat across the top of the hub.
Apparently I was told at the weekend that it tames the front end a bit.:thumbsup:

wat difference does itgive the car if you run the diff in low or high possition? do they have to match ?

Question for matt or mossy, when adjusting the rear toe in do the spacers have to add up to the same amount at the front and the rear. I think in the kit it has 2.5mm on the rear and .5mm at the front but also a 2mm washer the other side of the screw. If i wanted to add another .5mm to the rear to make it 3mm/ .5mm, do i need to add the same at the front but on the other side of the screw so both front and rear are equal? Hope this makes sense!!!!!:confused::confused::confused:

No you don't, just make sure they're equal left to right:)

just make sure the screw doesnt go too far through the inside of the alloy housing and catch on the diff.

Nice one! cheers:thumbsup:

I have a question regarding the layshaft above the slipper.. Did anyone notice, that if you tighten the nyloc nut up too tight it causes the transmission to become very tight?

Thanks

P

We already had this the last couple of days, check if you have the rear belt pulley the right way in.

Cruise.

Have a look on this topic

wheel base?
 

might sound dumb but how do you alter the whel base legnth?:confused:

Its dead easy, im hoping you have figured it out by now. But the rear inboard hinge pin has two clips per side, you can move them around to change from short, medium or long.

Those are very small adjustments, are they really noticeable?

Yep, can feel the difference. I use long wheelbase

What do use to do this.. Hacksaw Blade ?

How have you guys ensured that theya re exactly the same on both blocks ?

Kit should be here this afternoon so ready to get started..

Thanks for all the tips. :thumbsup:

A couple of things i did to the car, that i haven't seen on this thread was to put a extra nut (not nyloc, they foul the cover) on the slipper assembly, to help prevent it loosening, and i also changed the button head screws (2mm hex)for cap head (2.5mm hex)on the motor mount, i found the originals could easily round off, but with cap heads you can get much better leverage,and less chance of the mount moving in a big impact, and theres less chance off knackering the screw, the cap head will sit slightly proud of the chassis, but once the undertray is on, you'd never know.
hope this is useful to anyone new to the car.

Jay

do you still use this setup? I was thinking about getting the Oneway. how do you like it?:thumbsup:

Brass weights
 

Sorry, posted in the wrong thread:blush:
http://sphotos.ak.fbcdn.net/hphotos-..._5465339_n.jpg

big bore shocks
 

Hi, trying to re-build my rear big bore shocks last night for the first time and must be doing something wrong, however i put them together the shaft pushes itself all the way out, spent almost 3 hours last night trying to get them right, ive tried putting the cap on with the shaft fully in, fully out or in the middle but as soon as i push the shaft all the way in it pushes itself fully out!! Ive rebuilt loads of losi & associated shocks in the past with no problems but these have got me beat & very angry!!
What am i doing wrong??

CAtSX Battery Mod?
 

Hi everyboby,

my current batteries are 1.5mm to tall for the Cat SX. Instead of buying new lipos I was wondering if I could 2mm shims under all the bulkheads, hereby lowering the bottom chassis by 2mm.

Has anyone tried it?
What do you Schumacher guys think about it? Will the undertray still fit?
Have no experience with the Cat SX, but though t it was a good idea...

nic