XRAY - Model racing cars

Hi all... i'm lookin for a setup suggestion for my diffs..

I'm currently running 7-7-1 in the diffs; engine is a p5 with the 0.9 springs and xray shoes.

problem is that the rear end tends to want to come around really easily when i punch it after corners. barely 2/3 throttle and it looks ready to spin (partially due to the ridiculous p5 bottom i guess).

Question is what diff oils setup should i be changing to in order to lessen this? 5-7-1? 7-5-1?

appreciate any suggestions thnks!

try 5,7,3

thats prob. not gonna help neither? i have a P5 and i tried everything to calm it down a bit. the best way is to use a higher end pipe 083 or JP2 .
Then you can put 1 tooth higher on the clutch bell. and if your running aluminum clutch shoes then put the fiber ones back on. i played w/ the bells and ended up using a 14T. it worked great.(the ofna ones are cheap and work fine) the 15 took to much away from the beast. when i was trying to change the diffs i was using 3,5,1 so it wouldnt spin out. it was a tight track indoors. i really wouldnt try thr diff set up until you try the other stuff. 1st -bell
2nd-clutch
3rd- pipe
4th- diffs to suit your driving style.

Well their all opinions right? I vote for the 5/7/3, 7/7/1 is an extremely aggessive diff setup for exiting corners, remember that is the stock setup and designed for european tracks that are grass and concrete, they want a tad less steering in and a ton coming out.

Also make sure your servo saver is tight, this has been the #1 cause I have seen with loose rear ends. If the saver is loose and easy to move when you lock the servo, then it is too loose. It needs to be somewhat difficult to move it with your hands. If it is loose your car will always feel like it is wanting to continue turning on exits and erradic on entering corners.

Also increase your rear toe-in to 3 degrees, you can also change the front in-board toe by going to 1's pointed towards the center of the car.

I haven't seen your latest setup. I think I'm running pretty close to the setup you posted for the indoor race you were at recently. Was thinking about giving the 053 pipe a try this weekend.

I think I saw a set up sheet somewhere today that showed you were running the longer wheel base, does that help the rear traction on power coming out of turn?

nolec5 - congrats on your win. and yes i agree there's lots of good info here.

it rained two days str8 over here so my weekend was a complete washout...

ended up cutting up a new shell (touring car) and giving the xb8 a once-over (diffs are now 5-7-3 with GS oils and the wheelbase is maxed out). the car is almost the same as Joor's 'base' setup now! Can't wait to get it on the track again.... as soon as the weather clears up.

will be mixin and matchin' these pipes and manifolds as suggested to see what works... LHS has a good deal on a JP2 but really don't wanna splash out on a new exhaust unless absolutely necessary...

Nolec5- when u were running that 5-5-5 diff setup and won what kind of track were you running on?

xb8boy - track was fairly tight, lots of sharp 180 degree turns and a big, fast off camber section. Decent lap times were around 27 seconds, fast lap times were high 25's to low 26's. The track surface was sort of hard packed with a little loam on top.

By about half way through the 20 minute main, there were a couple of spots on the track that got really bombed out. But the XB8 handled these spots flawlessly. I think I turned one of, if not my fastest lap of the day at lap 39 of the main (42 total laps). When I saw that, I was very pleased!

I can't say how happy I am with this setup and this car. I ran a K2 for about 4 months and a MBX5 for about 8 months. I chased the setup the entire time I ran the Mugen and the parts were so expensive for the K2. I always felt like the K2 was a tank and felt that the best buggy, for me at least, would be the offspring of a K2 and an MBX5. So far, I think the XB8 is the perfect blend!!

The setup I was running yesterday was a Nov. P5, ofna 053 pipe, Mugen clutch with 1.0's, aluminum shoes and a Kyosho 13t clutchbell.

I ran 5/5/5 today as well, TQ'd but ended up getting 2nd in the main due to a flame out 20 minutes into the race (was about to lap second). I never got to try the 5/5/3 like I wanted. Instead I tried dark blue springs up front, but did not like the responsiveness it gave initially and push it gave exiting. I still think there is a diff setup out there that we haven't found quite yet. I will also begin working with swaybars to get the car to be more active rolling wise on the track.