XRAY - Model racing cars

Thats why its best to use the under the wishbone method on the rear.

Nah, would take the fun out of confusing everybody...

Actually it is standardized as for the rear the setup sheets clearly indicate the measurement should be taken under the rear arm. Sooo I promise all my FK'05 setups will measure the rear downstop under the outer rear edge of the rear arm. The front downstop I will measure under the lower screw holding the steering block as indicated on the setup sheet.

Ok back 'on topic again'
My thread is allready hijacked a few times before.

I made some further changes:
- lowered rc in the front (shortened camber link and raised the link on the inside)
- did top of shock in front 1 hole to the inside
- ride height 5 - 6
- downstop 0 - 1
- tires Sorex 24 / hpi orange inserts
- Changed toe out front to +1
and last but not least
- used the 4,5 degr. caster in front.

Result of this all was a very stable behaviour with good grip and very good exit speed.
By using the 4,5 caster i lost a little steering at corner entry. Tomorrow I'll be going to solve that. But how I don't know yet

But overall a good day with a best time (by air temp of aound 11 deees c) of 18,2 seconds. better time is possible, if only I stopped making at least 1 mistake per round

And now a question:

We copied (exactly) my setup to a brand new FK05 and the FK05 was very very oversteered at of throttle corner entry (only other difference was that I use the Vortex Brushless motor and the FK05 a nicely tuned brushed 12T motor).
My idea was that the FK05 should handle at least near the behaviour of the FK04. But it did NOT.
Where is our bug ?

What I noticed with the 05 is the car has A LOT MORE steering compared to the 04. I'll bet if you raise the front RC on the 05 car by putting the arms back in the middle holes in the bulkhead it will feel more like the setup you currently have on the 04 car.

Just a quick update:
Practiced again the afternoon and evening untill dark with my fk04. Changed the set-up again further and improved my time again: 18,02

Tomorrow i'll post a full setup with detailed descriptiom on handling to get some feedback on.

Richard, the fk05-guy at EVMC, is going to post coming day, I presume, some question about improving his set-up.

As promised:

Setup Joep Willemsen in VELP.

All positions (pos.) refer to the xray FK04 setup sheet.

Date: 21-4-2005
Track: Asphalt, Fast track, Medium grip
Air temp: 12
Track temp: 14
Car: XRAY FK04
Front diff: 1 way
Rear diff: medium
Internal ratio: 1,77
Pinion/Spur: 21/93
Rollout: 25,65
Shocks: alu
Spring front/rear: blue/light blue
Oil front/rear: 30w/30w
Holes front/rear: 3/3
Anti-roll bar: none
Tires: Sorex 24
Inserts: HPI soft (orange)
Motor/esc: Team Orion Vortex Brushless
Cells: GP3300
Body: Stratus 3
Caster: 4,5 degrees
Anti-dive/squat front/rear: pos. 2-3/4-1
Wheelbase: medium
Ride height front/rear: 4,5/5,5 mm
Shocks top front/rear: pos. 4/2
Shock bottum rear: pos. 2
Camber link inside front/rear: pos. 5/1
Camber link upright rear: pos. 1
Downstops front/rear: 2/1 mm
Toe front/rear: -1/-2 degrees
Ackermann (wheel/saver): pos. 1/1
Camber front/rear: -1/-2 degrees
Car weight: 1505 gr with AMB transponder.
Weight distribution: 25% per wheel
All hubs and arms: medium

Ok, that was a lot of typing. But that will decrease when XRay introduces the setup database

Ok, for referral purpose. A Tamiya Team Driver with a 9 turn motor did 17,4 seconds in sunny weather approx. 18 degrees air temp.

I made the car harder and lower compared to Frans's and Tony's advise to get more steering respons. and that worked! I only have to avoid the two well known 'bumps'

I must say that it was spectacular yesterday evening in almost dark when I didn't avoid the bumps (because I didn't see them) to see a lot of sparks coming from under the rear of the car

Now, my wishes of improvement of this setup.
1) I would like a little more 'almost' oversteer entering off power a corner. So more tricky.
2) And in contradiction with that I would like to have a little more on power corner exit steering.

Any advice is welcome. Thanks in advance.

Greetings,

Joep

Hmmmm, absolutely NOT happy.
Tested today the setup again but then with Sorex 28. Did not work. Oversteer entering en understeer out of the corner. Made the front camber links longer, used anti-roll, softened the whole car 1 step raised the car 1 mm all around and decreased droop at the back
... and ... ended up with .....
oversteer entering and und understeer exiting
But with a little throttle entering I was able to do an 18 flat.

Pffff. Going to do big maintenance, long thinking and coming weekend a lot of testing again.

Gr.