one thing i really dont like about this chassis is setting pinion. the hole seams very small

Take the top plate off. Easy peasy then

I wouldn't run so little droop in the front, at 7 or 6 mm droop you're not getting enough weight transfer to the rear tires when you are on power. 4.5-5mm sounds more like it, especially when running 13.5 boosted, it's spinning out on power, so the more weight going to the back tires with more droop, ( more droop is smaller number) when you hit the throttle the more traction you'll have going to the back tires!
Just my 2$

Yeh that sounds reasonable! I did wonder if that might be causing the issue but many of the setup sheets I've studied seem to run 6 or more droop at the front

For sure.

it is as maxepower said, and I use allways 3 deg toe in in the back and 2k rear diff oil in low grip conditions -(put away the upper screw at top deck at the motormount to have more flex)

if i have enough rear grip and want to have a fast left-right-transfere than i increase the front droop. 6 or more
Also- specially for fast corners into a straight it helps to have more weight in front.- if you have in this section problems with on power understeer -then go harder diff oil! - I have 3 diffs -2k- 4k -6k
but also, as mentioned before, dont forget the front setup too-- reduce the initial steering.
it also depends on the tires, tire additive and the minutes of how long does the additive have influence on the tires.

Ran again tonight on a higher grip carpet but still changed front droop to 5. Much better.

The car has developed a lot of slop though which is a little dissapointing, my hobao h4 didn't get any slop in 2 years

First weekend with the x was a success. Just put a basic staton set-up on it and threw it down in our "Carolina Hot Rod" class, and didn't touch it all day. Car handled great. At this point I'm thinking of getting a second for VTA and using the same starting set-up.

Carolina Hot Rod is a fun class we started to not worry about much of anything. It has only one real rule... you must run USVTA tires and rims. That's it. Any motor, any body, any battery, and no weight minimum. I had a 17.5 in it, and it was great. Tires are the limiting factor in the class, they really can't handle much more than that in an 8 minutes race.

have a couple questions
im still Not having very good luck with exotek c-hubs. the screw comes loose(so i change knuckle) and for some reason they seem to bind
have any of you guys used c-hubs from another manufacture ? that are better then tamiya ones
i have smj progress springs what ones to i use for grey carpet 2.8f 3r? 40w oil

I have no problems with the hubs. I used thread lock on the screw per instructions. And never had an issue with them binding up. I used the stock top hat spacer on top on the hub as it was shorter than the exotek one. I also had to shim the hub in the arm with a .1mm shim to get the slop out. But no issues with binding on my TA07, EXO6, or 419x.

But if you are really having issues and not happy with them, you can try the TA05 hubs. This was the go to alternative to stock hubs before Exotek. They are softer than stock, but I never had any break.

.

I use the ta05 hubs and have yet to break one after several meets and a few decent knocks..

Same here..

I would suggest always using a plastic alternative to aluminium hubs. Aluminium will bend even slightly and you will have a car that is never quite right.

Hi guys.

Really get used to my 419 now and its starting to perform well.

One question I have is about roll centres.

I bought the car second hand and on the rear its running xa blocks and 1e. However for some reason there is a tinu shim under all the blocks front and rear.

Should I ditch these and tune my roll centres from the camber links?

Non of the setup sheets I've read have any spacers under the blocks..