xb4 2014 very bumpy and wet astro set up

alex97 · #1 20-01-2014

hello
After my first run with my xb4 I was a bit disappointed with how it was. I was using green mini pins that ive always used and they work very well on my b44.1 avid. The first round was terrible I only got 7 laps and I usually get around 10-11 in the first heat when the track is wet. I did take all the flex chassis screws and that did help a lot but the car was still not as good b44.1. is there any thing that I can change to make it drive any better.

thanks

luniemiester · #2 20-01-2014

It would help if you could post your current setup so we have an idea what you using at the moment. You don't mention why its not doing what you want compared to your previous car?

Shock oils, pistons, springs, diff oils, roll centres to start

andys · #3 20-01-2014

Nothing is as easy and forgiving to drive as a B44!

Did you set the slipper right, as I assume you will be running kit setup.
Too tight a slipper and it will be an animal in the wet.

I find that no roll bars / 10K oil all round / shock middle on tower / inner on wishbones (max droop) Kit pistons (40 oil front) (25 oil rear) and it works a treat. Never run greens though these days, Yellow's always or Balistic's if it's wet outdoors.

Think it may take you a while to get happy with it, something must be very wrong to go from 10/11 laps to 7. Maybe flog it to me and cut your losses

alex97 · #4 20-01-2014

Thanks Andy. I never built the kit I bought it built but not run off of this forum so I DONT know the current set up but it has stock everything. There is another xb4 where I race and his car felt much nicer than mine so I may see how he set his up.

alex97 · #5 20-01-2014

What tires do you use in the wet ?

andys · #6 20-01-2014

Quote:

Originally Posted by alex97

What tires do you use in the wet ?

Ballistic Buggy Greens if it's really wet.
Damp - New Yellows.
Also D-Boots are quite good as a backup.
If it's pouring down / muddy, on grass - TR32's are ace but rare.

If you did not build the car - I would strip it down and start again to be sure it's right

alex97 · #7 20-01-2014

thanks I may as ive got two weeks before I next race

tomtom · #8 20-01-2014

You shouldn't have issues, the car can run anywhere, but you need to work your setup, maybe lighter shocks, especially rear, longer links and shocks on inside on wishbones and outer on tower.
Smoother delivery on esc might help a lot too, or going up on pinions, lighter diff oils, full gurney wing to lock the rear down.

Tyres are essential, I found greens to be too hard to work at all on wet, would prefer fresh Silvers or fresh Yellows, you could even try blue but a Ballistic works even better, especially on corner exit/power out of corner were all the bad s... happened.

Take a look at low grip dirt/clay setups to have an idea. It work but the car need a whole new setup.

alex97 · #9 20-01-2014

I've added 10k to the rear diff so now they are both 10k and made the front steering link 31mm even though stock it 32mm they seemed to be pointing in a bit much. I was thing about moving the shocks back but seeing that I wanted to lower the traction I think I will leave them for now. When I cheeked the slipper it was about 30% tighten so I turned it down to 10%. Before I put my ESC I did an update and now I have turbo so I may turn that off.

Thanks for the help

alex97 · #10 21-01-2014

Rebuild finished, I also turned the turbo down it was on 30° but know its 15°. I DONT have a clue about the turbo setting so please say if its wrong.

dale · #11 22-01-2014

Quote:

Originally Posted by alex97

Rebuild finished, I also turned the turbo down it was on 30° but know its 15°. I DONT have a clue about the turbo setting so please say if its wrong.

If you're using turbo make sure you have a long delay (I use 0.7s) and a fairly slow ramp so it doesn't kick in too violently (I use 3deg/0.1s).

Or just turn it off if its wet.

andoiwebb · #12 22-01-2014

why are you using 10k in the rear diff?

shaun m · #13 22-01-2014

Quote:

Originally Posted by andoiwebb

why are you using 10k in the rear diff?

+1 , thats what i wondered , as its loose on the rear end anyway !!

andys · #14 22-01-2014

I tried 10k front and 10k rear based on a setup sheet from Martin Bayer.

Thought i'd give it a try as I have previously ran lighter in the rear. Car was great at Worksop indoors - did everything I asked of it. Might try lighter in rear next time and see if it's even better.

I do run the Ralls Rear Tower though - which helps with rear traction due to the additional camber mounting points.
In fact the traction was so good - I ended up removing the weight I used to run in the rear.

alex97 · #15 22-01-2014

I'll give it a try and if I don't like it I try 5k again or maybe 7k. The diff's in my b44.1 car quite tight and it find its just nicer to drivre, maybe different on an xray.

neallewis · #16 22-01-2014

Quote:

Originally Posted by alex97

I'll give it a try and if I don't like it I try 5k again or maybe 7k. The diff's in my b44.1 car quite tight and it find its just nicer to drivre, maybe different on an xray.

I've tried all weights 1000 to 15000.

7k/3k was the best all rounder for me. 5k/2k was also decent on low grip, but not so good on variable grip tracks like carpet/slippy floor we run indoors span/diffed out on the high grip.

7/7 was good on RHR clay, I preferred this over 7k/5k.

I thought 10/10 was loose on the low traction, so probably best for full carpet/dry astro tracks.

Shock setup, go with the ralls racing setup.