snuvet75

iTrader: (16)

So given all this info, I was thinking why Project 4X out of box performance is bad.
1. Chassis too stiff for stock racing. I think it might do better in mod racing.
2. Suspension is too soft in default.
3. Car bottoms out in default set up. Prob from no. 2.
4. Default RC is too low.
5. There's no actual anti roll bar like set up. I think this is one of the biggest problems in this car. Roll dampers resist rolls but it doesn't sit down the ipsilateral side like ARB does. So we have to control rolls with roll/heave dampers and roll centers only. Droop is the only closest thing to ARB effect on ipsilateral side that Project 4X has.
I'm still not wanting to buy all those option parts (They are in the shopping cart of mine though lol) until I know for sure the car won't work w/o them. Well I only ran the car one day.
What are your thoughts?

dan_vector

iTrader: (27)

Get the new parts on the car. I ran the kit configuration lots and whilst I got the car good on high grip carpet I struggled once the outdoor season started. The new parts with the harder roll configuration fixed all my issues. The car is really very good once you've got the options on the car.

I have a feeling we will see a 4X EVO kit released soon with the upgrade parts included like they've done with some of their offroad cars recently. I think you'll struggle to make much progress without the parts.

WagwanBumba

iTrader: (1)

I managed to get the car to work without any of the funky option parts. I haven't tried the option parts yet - was hoping to today but got rained out. Doesn't need the option parts but from what folks say, makes it a lot easier to drive. Suggests to me that the option parts just widen up the setup window.

snuvet75

iTrader: (16)

Yeah I thought about it last night and am leaning toward it. A few questions.
It seems the linear suspension kit is a must as they report digressive action with kit link. What is the length of setscrew since desoto doesn't have the kit in stock. I would have to buy the set screw separately. It seems either 8mm or 12mm.
Short RRS link may not be necessary. The traction can be sought after with other tuning. No? It's pretty cheap anyway though.
The idea to use short stiffener with VTD instead of single kit stiffener still doesn't convince me. So convince me Dan. Thank you.

snuvet75

iTrader: (16)

I agree that RC makes the scrubbing. Mine has same location on sides and rear. I meant soft damping like you said.
I know it's a different car but ARB is such an important tuning tool that Project 4X is lack of. But you're right. We have roll spring and damper both in replace of ARB. I'll report how the car is on next meeting. Thanks.

dan_vector

iTrader: (27)

It's 8mm setscrew. You need the brackets and you can make the actual link yourself. The short RRS links helped stop that over rotation feeling in hairpin turns. The VTD won't work with the kit chassis stiffener installed. You can just cut the kit stiffener or use the new front only part. You can see for yourself - leave the kit stiffener fitted and install the VTD you'll notice the car is then totally rigid as concrete. Remove the kit stiffener and the chassis flex feels much more conventional and uniform.

I am about 0.2-0.3 seconds a lap faster with the upgrade parts installed and most importantly I can do the same lap time lap after lap for the entire 5 minutes run. The car is super easy to drive now and is fast. Before the update it was more difficult to drive fast and I struggled with consistency.

By the way I'm running stock roll centres except just 1mm less shims under the rear upper arm mounts. The lower mounts and front upper mount is all at stock. I don't believe that there is anything majorly wrong with the kit RC's at all. The roll dampening was way off in the kit but we've fixed that.

The 4x doesn't need an ARB, you can tune much more with the roll dampers and springs than you could ever tune with a traditional ARB (forget the term ARB!). You've just gotta get your head around this new philosophy. I rarely change heave anymore it's sorted. I now focus mainly on the roll dampers and springs to get the feeling I like from track to track.

snuvet75

iTrader: (16)

Thanks man. I know I can't use kit stiffener and VTD at the same time of course. It will be a rock as you said! lol

dan_vector

iTrader: (27)

I hope you can get the car working to your liking. I mean we all drive differently and want different things from any car we run.

The one thing I've found with the 4x is that it is VERY responsive to even the slightest setup change which you can really feel on the track (in a positive way!).

I never had that feeling with the ERYX 4.0 which did respond to changes but the changes had to be quite big for me to feel them. I mean I could hardly feel the difference going from 1.2mm ARB to 1.4mm ARB whereas on the 4x I can really feel the difference going between only one grade of roll spring or dampening.

RC MARKET

iTrader: (12)

New Hard Wheel Hub

WagwanBumba

iTrader: (1)

Past couple of posts, I've said I need to try the car with the new upgrades ... I did so this weekend.

WOW! Car is SUPER easy to drive. I'll have to fill out a setup sheet once I unpack things at home but upgrades used:
VTD 401738
Linear Suspension 401742
RRS Short 401747
I cut my center brace because I have a spare one

dan_vector

iTrader: (27)

Told ya

The car is pretty good with the updates eh! I reckon the EVO car will be with us soon and that's even better

snuvet75

iTrader: (16)

So I ran yesterday. The loose rear was the issue all day. Outdoor asphalt, medium track and medium grip. It was more so compared with my past cars. The car was turning very well but in return, loose rear. It seemed total amount of grip in rear was generally pretty low. I managed to get the car around track w/o big issues but had to focus on limiting steering input all the times. (Was still 2nd fastest on the track with 6 year old Reedy motor that's been abused)
I started with 0 hole roll piston F/R, medium high lower hinge pins F/R, 3mm shim on inner pivot F, 2mm R, 4mm shim on outer RRS link, and everything else pretty much similar to default w/ no option parts. Tried less droop rear, lowering height R and less shims on RRS but didn't make any improvement.
Sometimes, the car felt as if it lacked roll in rear or rolls too late to grip the track but I could be wrong. Inside rear tire's temp was about 5-10 degree F off. Is this what you guys experienced with stock kit set up?
BTW, I broke the turnbuckle twice already on the suspension linkage (connecting rod between upper and lower front arms) after lightly tapping the board a couple of times. Maybe I should free up the ball cups on it a tiny bit more so it pops out in crashes instead of breaking the rod. But honestly, I think the part is too weak for its purpose. Won't matter now cuz I'm buying the linear suspension kit.
Despite all these issues, I'm happy how well it turns and stays low in ground w/o scraping chassis too much. Looking forward to having the upgrade parts and trying them.

G-rem

iTrader: (2)

Hi there,

at rear, can you please tell me what would be the influence of using another hole for the upright linkage position instead of the default setup in the manual (see step 60, p. 32)?
I assume the rear toe rod will not be straight anymore compared to the stock position, but what will it influence?

Thanks in advance for helping!

G-rem

Airwave

iTrader: (1)

Changing the length of the rod will change the way the toe will vary in the curves. Longer rod means smoother transition of toe-in, from what I understood.

Airwave

iTrader: (1)

With the help of a friend we have worked on the arms position. I really want to try the lowest position in the front. With that insert, the arm touch the lower deck and you can't have any droop... That's a design flaw! We had to modify the lower deck so we can have 2mm of droop.

I had no time to test the car in this configuration... Obviously we also had to change rods length.

The other thing I had tested is brass bushing instead of ball bearings in rockers. The slop has totally disappeared. That's a win!