XRAY - Model racing cars

I probably should have known better. I headed out to the ACT Titles on the weekend, being held at the ACTRCCC's track in Canberra with no practice and little preperation. I didn't expect to win, possibly make the A's, given numbers, but would not have minded being in the B's, if the car had been working properly.

OK, heres what happened - I took off from the starting grid in round 4 (I'd missed 1,2 and 3 due to work commitments), turned in to the sweeper and imideatly spun out

Over the next day and a half of racing, I tried just about everything, springs, shock angles, rear droop roll bars, slight roll center changes and of course tyres. While all these changes helped a bit the basic triat to spinning in tight corners, bit with power off and power on stayed.

The car seemed to pitch over, and lift the inside wheel off the ground, about this time, the car would spin out.

Heres the setup that I finished the day with. If I don't mention a particular setting, assume it's as per the default FK05 build.

Setting - Front/Rear
Tyres - Foam, UFRA 40F/Foam, UFRA 42R
Springs - 25lbs/25lbs (Blue, one shade up from violet)
Dampers - 3hole, 60wt/3hole, 30wt
Ride Hight - 8mm/8mm
Castor - 3deg blocks. 0deg in the arms
Droop - Not sure, set to shorten shocks enough to stop springs from moving up and down.
Shock Location, front upper - Outter most hole
Shock Location, Rear upper - Inner most hole
Shock Location, Rear lower - Inner most hole
Multi Diff - Solid One way.
Rear Diff - Medium

The Track was Trated with traction compound, to the point that when you walked accross it, your shoes would stick to the surface, so there was a hugh amount of grip.

Having had a few days to think about this I find myself looking at the roll centers, would moving the front and rear roll centers to there uppermost position (moving the roll center closer to the Center of gravaty) help?

Sorry for the long post but any advise, guidence of suggestions will be greatly appriciated.

Mark.

How about your roll center?

And is your diff still okay, are you sure your rear diff is running smooth?

Thanks Darren,

I'll check out your setups and give them a go.

BTW: Thanks for your advice on tyres and congratulations on the win.

THanks Guys,

Darren,

I've rebuilt my car and setit up accoring to your Kambah setup, should be intersting. I was chatting to Gary and he was saying that you would not mind if I gave you a call about setups. Thanks for this, I won't be back at Kambah until November, work has me rostered on everyweeknd this month . I'll be trying your setup at Indoors but I'm expecting to have to make some changes as it's a much tighter track with less grip.

Tonyv,

I'd not heard that. My Tyres were trued to 58mm with side wall protectors on them so would this give a similar effect?

Dnte5,

Wow, broken diff balls!! That's impressive, I've not had an Xray Diff fail yet, BTW rear diff has been checked and is fine.

Everyone,

Has anyone else had the layshaft bearing fail? The larger 6x10x3? The car's only done 16 runs and this particular bearing looks as though it's been jamming up on the layshaft, I've tried to clean it but while it's freer it's still quite rough and will be repaced.