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byebye
2014.03.03, 06:42 PM
I figured no matter how many times I hit "new posts" I won't see much if I don't post myself ;)

So I'm going to document my 90mm class build for racing with the Washington, D.C. GTG club.
Body- F40(in the mail)
Chassis: MR-02 w/4562 2x2 FET upgrade
Front body clip- PN Racing alloy with carbon F40 specific(in the mail)
Bearings: PN Dry, steel
Wheels- Ferrari 458 italia ASC plastic, +2 front narrow, +3 rear wide
Wheel locks- stock plastic
Tires- Kyosho 30 front, 20 rear
Knuckles- -2 camber, brand unknown
King pins- polished , brand unknown
Tower bar and bottom front brace- PN Racing narrow kit
Tie rod- Kyosho "0"
Motor pod- PN Racing 90mm mid-mount with disk damper(plates and associated parts in the mail)
Motor- Atomic T2 w/9t pinion
Differential- Stock
T-Plate- Kyosho stock

Side profile with previous Abarth body. Yes, this is an MR-02 chassis. I stacked a 4562 2x2 on it years ago and it was previously my mod car before the MR-03 came out. I recently sold a bunch of stuff and this was left over as everyone runs the MR-03. It was already serving Abarth duty and I used it during a 90mm class race with the Washington DC crew. The motor is an Atomic T2 with a 9t pinion. I had to turn the throttle way down for this to even be drivable. It's really a fun setup and this new motor mount reduces the roll a lot.
http://mini-zracer.com/mini-zgallery/data/1453/side_profile.jpg

Side profile low. I don't have the F40 body yet but I'm curious if this damper system will clear the rear end. Our Washington DC club 90mm class only restricts to the 90mm wheel based bodies. So after some research I decided to spring for the F40. The wide offsets should really improve the stability over the setup for the Abarth. If all else fails I'll go back to the Abarth and Arch2b will ask me why I didn't listen to him in the first place :)
http://mini-zracer.com/mini-zgallery/data/1453/Side_profile_low.jpg

The damper looks odd to me but only because the plate is on the motor instead of on the chassis. This is the case obviously because of the 90mm mid-mount. The PN Racing mount did not come with any disks, springs or posts unknowingly. I also noticed that it didn't sit quite parallel with the chassis so I used the rubber o-ring from a stock diff on the bottom screw of the damper plate arm causing it to pivot. I tightened both screws until it was somewhat level under the weight of the chassis.
http://mini-zracer.com/mini-zgallery/data/1453/Rear_suspension.jpg

I noticed that you don't have much wiggle room between the chassis and the motor can, the motor and the diff shaft and the pinion and diff gear. I had to reroute my motor wiring and resolder the positive under the tab in order to have some clearance from the diff shaft and some adjustment for the pinion mesh.
http://mini-zracer.com/mini-zgallery/data/1453/Motor_clearance_from_diff.jpg

I'm using the PN Racing MR-015 narrow top and bottom tower bar kit which converts my stock MR-02's wide front to narrow. I did this to specifically run the Abarth body with a -1 narrow wheel. This narrow kit is pretty solid and with the -1 wheels provides good clearance for those brushes with the RCP rails. One thing I noticed when running a -1 wheel is they would rub a little on the tower bar. It wasn't a show stopper and now I'm running wheel offsets for the F40. The stainless kingpins are a little tall and needed a single washer to fill the space between the c-clip. The suspension is fairly smooth and the steering has been pretty good. I know the A-arm kits only come in wide and I could get away with it now that I'm running a body with a wider front. Maybe in the future I'll upgrade.
http://mini-zracer.com/mini-zgallery/data/1453/Front_suspension.jpg

So far this has been a pretty fun build from a spare car. Running the Abarth was really fun but I wan't to try the F40 and see how much better it could be. I don't see myself upgrading to an MR-03 as the class is open. In order to mimic this setup I would have to change the FET's and I really don't feel like all that work. Beside running an MR-02 against MR-03's is an exciting challenge.

I will update this thread as I recieve my parts.

Kris

EMU
2014.03.03, 09:29 PM
I believe that the damper will clear the F40... but you may want to use a wide tower front end or A-arm... Since the F40 is wide ;)

arch2b
2014.03.03, 09:57 PM
for the record, the fiat on that chassis was driven to a win ;) it rolled for sure but given the motor you have in it, it's a given but it really did drive very well.

which F40 did you happen to get?

byebye
2014.03.03, 10:13 PM
I believe that the damper will clear the F40... but you may want to use a wide tower front end or A-arm... Since the F40 is wide ;)

Yeah I would but I gave up all my MR-02 stuff :o. I've yet to run the F40 to see if it's worth the time. I only spent money on the body.

for the record, the fiat on that chassis was driven to a win ;) it rolled for sure but given the motor you have in it, it's a given but it really did drive very well.

which F40 did you happen to get?

I bought the white body. I did get an offer for $30 for an ASC. I plan to paint this one.

arch2b
2014.03.03, 10:17 PM
i'll look thru my bits, i could have sworn i still had a wide tower bar for the mr-02.

byebye
2014.03.03, 10:26 PM
i'll look thru my bits, i could have sworn i still had a wide tower bar for the mr-02.

I'll swap it if you have it. I know K doesn't come to HFAY so it would be a while before I could ask him. The wider front would reduce stiction. This is a "for fun" project that fills the tinker itch. I did put together my AM Airboat but thats for another thread.

EMU
2014.03.03, 11:28 PM
If Arch doesn't have a wide tower, let me know, I am sure that I do... in some form or other. I think I have a JPL camber/caster upper bar, and a large bunch of wide lower bars from my MR015 towers... so you can have a unique color scheme to say the least...

byebye
2014.03.03, 11:31 PM
If Arch doesn't have a wide tower, let me know, I am sure that I do... in some form or other. I think I have a JPL camber/caster upper bar, and a large bunch of wide lower bars from my MR015 towers... so you can have a unique color scheme to say the least...

Coolio EMU, I'll keep you posted.

Pierro
2014.03.04, 02:07 PM
Good luck with your new set-up!

The F40 is for sure a really nice car to drive because of it's stability and agility.
I personnaly also loved to drive the toyota celica in 90mm. This one is a little more difficult to drive because I drove it with wide front end and 0 wheels so the wheels tended to catch up the walls. Something you won't have on the F40.

You may consider using 19mm wheels on the front for clearance as the hood is pretty low on the F40. I used the F40 for month in our stock challenge in 2012 and 2013 and I was able to put it where I wanted on the track.

I do prefer the atomic 90mm mount to the Pn as it has better clearance. I could use the mount with a F355 with minor triming compared to what I should have cutted out to clear the PN.

EMU
2014.03.04, 05:33 PM
i 2nd the suggestion for 19mm front wheels. if you plan to true the tires, you can get away with 20mm wheels.

arch2b
2014.03.04, 05:39 PM
R246 has 17mm wheels if i recall correctly. I believe this is what i have on my DS3. i always seem to have issues with tires rubbing on the body when turning. :rolleyes:

EMU
2014.03.04, 06:26 PM
R246 has 17mm wheels if i recall correctly. I believe this is what i have on my DS3. i always seem to have issues with tires rubbing on the body when turning. :rolleyes:

17mm may be a little too small, unless LM front tires are used. 19mm are good enough for the clearance on the f40. using the PN carbon clip also helps adjust the clearance a little. i would recommend removing the sideclips, and moving them down a little to raise the body in the rear slightly, to increase clearance for the damper, and rear wheels (since the vents directly above them tend to rub a little if the body is low, and thats an instant traction roll. i tend to shave off the entire vent for clearance, and tape/sticker over it...

You may also want to try to reduce some weight from the rear bumper... i removed the wing and installed a Reflex wing myself...

arch2b
2014.03.04, 07:06 PM
tape the tires, which one would normally do, and it's fine. i've been running them for 6 months or so with no problems.

KWT
2014.03.04, 09:31 PM
Kris,

Let me know what you need.

arch2b
2014.03.04, 09:35 PM
I couldn't find my bar, must have given it away already.

byebye
2014.03.05, 08:16 PM
Thank you all for your interest and help. I received the rest of the parts today and installed them.

First order of business was to lightly glue the side clips so I could dry fit and modify from there.
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2612.JPG

You can see that the 458 offset is too wide. I also tried fitting a set of +2 wheels fron PN Racing and those were slightly too wide as well. Third pic is ) wide wheels which were too narrow.
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2613.JPG
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2615.JPG
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2616.JPG

Next move as suggested was to raise the body by moving the side clips lower. You have to shave the two bumps off the mounting slots(2nd pic) in order to raise. I put them flush with the bottom of the mounting slots.
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2617.JPG
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2618.JPG
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2619.JPG
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2620.JPG

Fits good now!
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2625.JPG

byebye
2014.03.05, 08:18 PM
And here is the chassis with the disk damper all together as well as the carbon nose clip for the F40.
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2621.JPG
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2622.JPG
http://mini-zracer.com/mini-zgallery/data/1453/DSCF2623.JPG

I don't know what these wheels go to(the rear wheels, not the front) but I believe they are +1 all around.