XRAY - Model racing cars

My son and I have just bought and built a T1FK05. The build quality is excellent and easy to work on. My question however is this....

We race stock 27T at 2 venues where the track is carpet and very small and tight. We use rubber tyres (Schumacher Carpet Dragons or T27 tyres). At these venues we gear our cars for punch and top speed is rarely an issue. Our ratio is typically between 10 and 11.

We are finding our current setup very loose and generally we don't seem to have the grip we had with our previous Schumacher cars that we have replaced.

Does anyone race at a similar venue and if so can they send me a proven setup. At the moment we are running close to that suggested by the manual. In particular we need camber angles for front and back, front toe-in angle and rear toe-in angle. Any other suggestions would also be useful.

Our problem is that we get very limited time to test at these venues and a good initial setup would kick-start our progress. Thanks in anticipation.

Yes, I drive at Warfield club which sounds similar.

A few suggestions for you:

Shortern the wheel base so that you only have 1mm in front of the rear wishbone. This has a major impact to tieing down the rear end.

Place a 3mm spacer behind the rear wishbone to provide 3 degree of toe-in.

Place a 2mm spacer above the the pick-up point on the front up-right and that should have you fixed.

The FK05 has immense mechnical grip - much more than previous XRAY models - so run Blue Springs all round - otherwise you'll find the edges of chassis drag on the carpet at every corner.

Then to provide some stability, close 3 holes on the front shocks and leave them all open on the rear.

In terms of the downstops, I'm currently running 1 FR and 5 Rear.

Best of luck, Mark.

Mark,

Thanks for your suggestions.

I have a few questions about your comments.

OK on wheelbase reduction.

Ok on rear toe-in. This was the same with the Schumacher Missions. We ran 3 degrees on these to prevent them from being tail happy so I've already seen the benefits of this change.

I want to make sure I understand you about the 2mm space on the front upright. Do you mean under the ball joint on top of the front C-hub (lifting the upper linkage)? I assume this is to lower the front roll centre?

OK on the shock holes. I assume you are running 30weight oil?

One further clarification point about the downstops. I assume you mean 1mm and 5mm below the level of the chassis (with shocks disconnected)?

What camber angles do you run front and rear. We ran 1degree on our previous cars. Can I also assume that the front wheels should be parallel?

Sorry to ask so many questions but this is good information and will save me an awful lot of testing. Next race is tuesday night (Leighton Buzzard).

Your help is really appreciated.

Adrian

Dave,

I've been meaning to talk to you about the T1FK05. I didn't realise that you posted setups on the MKRCTC site. Just in case you haven't realised that its Adrian And Mathew. The rain this weekend has prevented me from speaking to you so I posted the questions above.

I'll talk to you on Wednesday at the Warriors series at the outdoor track.

Thanks for your reply.

Adrian (Hall)

Dave,

I looked on the MKRCTC website but its a big place! Where exactly is the setup you recommend?

Adrian

Tonyv,

I'm beginning to understand what Mark was meaning. Raising the front roll centre would give less grip at the front, and so would balance the car better.

Tonight I will implement all of the above modifications in preparation for tomorrows racing and I will post the results on Wednesday.

If anyone can give a quick reply about the camber settings and toe in (front), I can set these accordingly but if not I'll try 1deg all round and parallel at the front. I'll use the above mentioned 3deg at the rear.

Thanks for your help.


Best Regards

Adrian

Hi - herewith the answers to your questions.
I actually run 1.5 degree camber on the front and rear. Sometimes go to 2 on the rear.

On the downstop - I use a Hudy downstop measurement tool which comes in their setup systems. I measure beneath the front upright (castor block) screw and then using the base of the wishbone at its end point on the rear furthest from the car - ie. the very corner of the car. This is the same measurement points they use on this sites setup sheets.

If we are on the same page, then your shock absorber springs should have just a very small bit of play with them fully extended - and the drive shaft will be approx flat.

I have no front toe-in.

Works for me. Best of luck.

Mark.

Mark,

Just finished setting up the car for tomorrows racing. I've used your setup exactly except for the springs (only have the kit springs at the moment, front white and rear yellow). I'll let you know soon how it went. Your help is appreciated and the other people who have contributed.

Thanks

Adrian (ademission)

Been a while since posting on the forum but glad to see this post about small tracks. I can agree with all of the settings and did have a similar setup to provide some tweaks.

The car has required some very different driving from what I was used to, xray t1 with c-hubs.

My current Setup is also available online under my name but the setup i suggest below is probably more suited.

A more balanced car was the following,
Blue fr 2 clicks 30w
White rr 1 click 30w
1.5 camber all round
downstop 2 fr 5 rr
0 deg toe fr 2 deg rr
(with no weight 3 deg can take you the other way and destablise it)
2mm shim fr 1mm rr
1mm infront for wheelbase

The reason for me posting this is that its not far off the setup mentioned and gives more things to try ! All else was kit setup

roll bar front 1mm can help if you have too much steering into corners, I have also balanced the rear with weight due to it being very front biased !

By all means check out the current setup, but it may make a difficult drive I was just very quick with it like this.

Last time out it was 6-7 sec laps, is this the kinda tight technical ? (this was actually a more flowing track)

Thanks Col,

All very interesting information.

Best Regards

Adrian

Well done. From here you just want to make little changes (1-2) each week, otherwise it all goes wrong in my experience.

To check whether you need to step-up on the springs, look at the edges of the chassis. Do they have dark areas of black gunge from where it will have been dragging on the carpet? If so, you need to go up on the spring rate a little. I aim to have either nothing or very little.

Best of luck, Mark.