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AtomicCP
2017.01.09, 09:34 AM
Hey guys! I have an MR03 with the ATOMIC 94mm MM mount, PN Racing 94-98mm friction mount with a Hard spring on top Mid spring on bottom, Stock center shock, ATOMIC Mid Fiberglass T Plate, Wide front end, 0* knuckles, and ATOMIC Soft Green springs. I currently run Kyosho 20* radial tires in back and PIT 15* slicks up front. Im pretty new to Mini Z cars and seem to have alot of on power push. My off power turning is good but would like more on power for the sweepers on our track. I was thinking of going to a harder T plate. What are your thoughts?

byebye
2017.01.09, 09:44 AM
Sounds like you need more front grip. When I push I add a little camber and change tires. I also true my front tires flat all the across. I run hard springs up front and a carbon 3 T plate.

Kris

AtomicCP
2017.01.09, 10:05 AM
Sounds like you need more front grip. When I push I add a little camber and change tires. I also true my front tires flat all the across. I run hard springs up front and a carbon 3 T plate.

Kris

When you say you change tires Im assuming you went to a softer tire? I should note it pushes more after about 4 laps into a race. Im thinking my front tires are too soft. Also is the carbon 3 T plate on the softer or harder side? My set runs from 4 to 6 in .5mm increments.

EMU
2017.01.09, 01:14 PM
What body are you using? Camber/Carter setting? What differential, and how tight is it set, does it slip When applying throttle?

There are many variables that come into play when trying to dial in a car. I have no experience with the front tires that you are using, so cannot comment much on them.

Do you have the tires taped or glued to the wheels?

One thing that stands out is that you have relatively soft front springs. They will help the car into the corner, but will reduce steering from the mid corner on once they load fully. I would advise using a stiffer frp t-plate, and move up on stiffness with the front springs a little as well. You may be lifting the inside front tire as throttle transfers weight rearward, this reducing steering on exit.

By increasing stiffness on all four corners, the cat should have more similar behavior on corner entry as corner exit.

Your disc damper spring setup, with a harder top spring relative to bottom spring will also induce on throttle push. So that may be the first line of attack to reverse the springs and see if it exhibits the same or opposite characteristic. With a harder bottom spring, you will keep more mass on the front wheels as throttle is applied, as the car will squat less.

Please update when you try some adjustments. Do one at a time, and run some laps (3-5 minutes) to see the results.

AtomicCP
2017.01.09, 02:13 PM
What body are you using? Camber/Carter setting? What differential, and how tight is it set, does it slip When applying throttle?

There are many variables that come into play when trying to dial in a car. I have no experience with the front tires that you are using, so cannot comment much on them.

Do you have the tires taped or glued to the wheels?

One thing that stands out is that you have relatively soft front springs. They will help the car into the corner, but will reduce steering from the mid corner on once they load fully. I would advise using a stiffer frp t-plate, and move up on stiffness with the front springs a little as well. You may be lifting the inside front tire as throttle transfers weight rearward, this reducing steering on exit.

By increasing stiffness on all four corners, the cat should have more similar behavior on corner entry as corner exit.

Your disc damper spring setup, with a harder top spring relative to bottom spring will also induce on throttle push. So that may be the first line of attack to reverse the springs and see if it exhibits the same or opposite characteristic. With a harder bottom spring, you will keep more mass on the front wheels as throttle is applied, as the car will squat less.

Please update when you try some adjustments. Do one at a time, and run some laps (3-5 minutes) to see the results.

I currently run the Nissan JGTC R34 GTR body, ATOMIC Carbon ball diff and 0* caster and camber. The tires are not glued or taped. Everyone in my club seems to think it is a waste of time and advised against it. I will try the disk dampener spring flip first. I can go up a spring and t plate as well. I will try those after the springs. Thank you for your input EMU!

EMU
2017.01.09, 04:38 PM
I currently run the Nissan JGTC R34 GTR body, ATOMIC Carbon ball diff and 0* caster and camber. The tires are not glued or taped. Everyone in my club seems to think it is a waste of time and advised against it. I will try the disk dampener spring flip first. I can go up a spring and t plate as well. I will try those after the springs. Thank you for your input EMU!
Taping/glueing tires is essential. Even if people don't feel that it is necessary. The sidewalls will occasionally peel up, giving inconsistent handling... And if you unload the diff at any point, the tire can balloon and shift.

I would definitely recommend that you start taping... or glueing the tires. On lower speed circuits, it is less vital. But if they aren't taped, it makes it much more difficult to work out irregularities in handling that could be tire related.

If you true the tires, it becomes even more important to glue/tape the tire. As the tire gets thinner, it needs more support to stay on the wheel.

AtomicCP
2017.01.09, 04:45 PM
Taping/glueing tires is essential. Even if people don't feel that it is necessary. The sidewalls will occasionally peel up, giving inconsistent handling... And if you unload the diff at any point, the tire can balloon and shift.

I would definitely recommend that you start taping... or glueing the tires. On lower speed circuits, it is less vital. But if they aren't taped, it makes it much more difficult to work out irregularities in handling that could be tire related.

If you true the tires, it becomes even more important to glue/tape the tire. As the tire gets thinner, it needs more support to stay on the wheel.Im using the R246 Volk CE28 wheels. Could you recommend a manufacturer of tape?

EMU
2017.01.09, 05:00 PM
I have had the best results with the r246 tape.

http://shop.tinyrc.com/product.php?productid=20137&cat=0&page=1

http://shop.tinyrc.com/product.php?productid=20136&cat=0&page=1

When taping, you want to be as close to the outside edge of the tire as you can.

These are two widths, for front or rear. Although you can use just the rear width, and cut off the excess with a sharp exacto once the tire is mounted.

AtomicCP
2017.01.09, 05:11 PM
I have had the best results with the r246 tape.

http://shop.tinyrc.com/product.php?productid=20137&cat=0&page=1

http://shop.tinyrc.com/product.php?productid=20136&cat=0&page=1

When taping, you want to be as close to the outside edge of the tire as you can.

These are two widths, for front or rear. Although you can use just the rear width, and cut off the excess with a sharp exacto once the tire is mounted.Been reading alot about taping the tires. Most guys are taping along the outside edge on the fronts and the inside edge on the rear.

EMU
2017.01.09, 05:16 PM
It depends on how you want The traction. I like a little more rotation on the rear tire, since I typically use a slightly harder front tire than many that I race with. I don't like my rear sidewalls lifting as I rotate through the mid corner before getting on throttle.

if I had a more aggressive front end, I would try to get a little more side bite on the rear by moving the tape inwards. Again, there are many tiny changes with these cars that all add up to how it is dialed in. Attention to these minute details can allow you to recreate the setup, and adapt it for different conditions.

Mike Keely
2017.01.09, 05:25 PM
I agree with everything that EMU posted. Taping the tires is more important then anything else he posted. Building a very smooth diff is also a big help. If you let the diff slip just a hair coming on the throttle it will help to not transfer as much weight to the rear wheels as you get on the throttle. I also like to use the PN spur gears. They cover the opening to the gap where the diff balls are so the diff stays cleaner for a much more consistent diff.

AtomicCP
2017.01.09, 05:37 PM
I agree with everything that EMU posted. Taping the tires is more important then anything else he posted. Building a very smooth diff is also a big help. If you let the diff slip just a hair coming on the throttle it will help to not transfer as much weight to the rear wheels as you get on the throttle. I also like to use the PN spur gears. They cover the opening to the gap where the diff balls are so the diff stays cleaner for a much more consistent diff.So tape tires down, let the diff slip alittle, change springs around, then try different tires up front if Im still having on power issues. Guess Ive got some work to do lol!

EMU
2017.01.09, 05:49 PM
Do it all a little at a time... So you can see the difference each one makes on its own.

AtomicCP
2017.01.09, 05:54 PM
Do it all a little at a time... So you can see the difference each one makes on its own.Ill start with the tape and spring flip first.:) Thank you again for the advice! Ill keep you guys posted as this progresses.

EMU
2017.01.09, 06:14 PM
The gtr also is a little rear heavy. Which tends to increase steering off throttle, but push on throttle. It's sort of the nature of the body. So, just be aware that the chassis setup will be a little different from body to body depending on its center of mass.

byebye
2017.01.09, 07:23 PM
All good tips from those that posted.

Kris

AtomicCP
2017.02.17, 11:36 AM
Sorry it took so long to respond. I have been taking my time with the setup changes and so far I seem to have a lot less push. I did each change one at a time and with each run it felt better and better. Thank you everyone for the help! I will keep updating this with any other issues that come up.

EMU
2017.02.17, 01:18 PM
If you don't have a top shock, you may want to consider adding one. A standard one will do, you are really just looking to add spring to the rear end to keep more mass on the front end when you get on throttle. Since you are already damping the rear end with a disc damper, an oil shock isn't as necessary as if you were not using a disc damper (tri damper). Take on mind that the more mass you transfer to the front on throttle, the less will be in the rear, which will translate to less traction in the rear.

Check out the 1/12 setup guide here: http://www.petitrc.com/index.php?/setupguide.html/
Although this is written for 1/12 scale cars, it translates well in theory for mini-z 2wd since there are many similarities between the setup of 2wd mini-z and 1/12 pan car.

In the section where it talks about side spring and center spring... You can think of that as t-plate options, since the t-plate covers both lateral and longitudinal support for the rear end of the chassis.

Side spring would relate to how stiff the t-plate is at twisting. Typically, a wider t-plate would equate to a stiffer side spring.

The thickness of the material would equate to center spring. In general, we don't have many options In this department. Generally there are only thick carbon like 3racing or reflex racing t-plate, thin carbon like Kyosho/PN/Atomic, or thin frp. I prefer the thin frp, and use a top shock to be able to fine tune the longitudinal spring rate with a spring that can be adjusted with spring rate (different spring), preload, and throw/down travel. This allows me to place my rear end exactly where I want it to be to transfer weight predictably.

Things that aren't touched on much there are the differences in body choice that mini-z has, and how much that changes handling and setup choices. Center of mass has a huge effect on how the cars handle, as does the overhang of the body past the wheel axles.

The body that you are using has a very large rear overhang, which means that you need more spring in the rear to compensate the additional mass. Spring ratio f/r is relative to mass ratio.

As always, if you have questions, ask away...

AtomicCP
2017.02.17, 05:36 PM
Seems like my body is kind of holding the car back. Do you have any 94mm or 98mm bodies that you prefer?

Mike Keely
2017.02.17, 06:01 PM
I really like the 599XX Ferrari. That with a PN Lexan rear wing. That is a 98mm body but you can run +3 rims all the way around it so it is really wide and stable. It is also very good in the way that it does not pull you into the side rails much if you hit them. If you notice that you get pulled into the side rails you can also switch to a +2.5 front rim and that will help also.

lfisminiz
2017.02.17, 06:48 PM
Seems like my body is kind of holding the car back. Do you have any 94mm or 98mm bodies that you prefer?

If you want to stay with 94MM, try the F430. My favorite 94 body.

EMU
2017.02.17, 07:02 PM
When choosing a body, there are a bunch of things to consider. Overhang past the axles as I mentioned above are a concern, but there are many variables to consider when choosing a body.

The Ferrari 599xx that Mike posted above is a good body for many reasons. However, I don't like how it drives. One thing that is important to me is the position of the cab (windshield).

I tend to prefer a cab forward design, with the windshield closer to the front wheels. To me, this puts more of th mass and down force on the front wheels and makes it a little more aggressive. The slight increase in front traction allows me to use slightly harder front tires for a similar amount of corner grip, therefore giving the feeling of more consistency.

With that said, other variables are wheel clearance, and ability to use wide offsets, mass of the body, aero grip, center of gravity.... But one of the most important factors for a race body is how it handles collisions and if it snags on the track divider. There are some bodies that are fast, but will snag the walls of get very unsettled with a side to side collision.

Some bodies run better with slower motors, others with faster motors. So, the class that you are racing should have an effect on body choice.

Many of the common go to race bodies, some/many may no longer be available:

94mm
Ferrari 360gtc
Ferrari f50
Ferrari f430gt
F430
F360
Lexus sc430
Corvette c5r
Nissan 350z (2005/2007 racing versions)

98mm
McLaren short tail (stock class)
McLaren 12c
Ferrari 458
Ferrari la Ferrari
Mosler (one of the most versatile bodies, and my pick for new racers)
Long McLaren good for mod on sweeping layout
Murcielago / lp670 good for low traction, generates a lot of grip

There are others, but this is just a ballpark

AtomicCP
2017.02.22, 11:15 AM
Ive been looking at the 458 GT2 body. Dont know if I want to go 98mm or try 96mm. Any thoughts?

AtomicCP
2017.02.22, 11:18 AM
If you want to stay with 94MM, try the F430. My favorite 94 body.

Does it get hung up on the track barriers?

TeeSquared
2017.02.22, 11:35 AM
Does it get hung up on the track barriers?

In my experience, the F430 is one of the many bodies that tend to get wedged under the rails on RCP. The front splitter is a mixed blessing. Definitely makes the body more rigid/durable, but the aforementioned "wedge" issue can be frustrating during a race. Some people grind it off but then I'd want to reinforce the front inside of the body shell.

lfisminiz
2017.02.22, 11:58 AM
Does it get hung up on the track barriers?

I have no lip on mine and it's one of the best on the rails.

lfisminiz
2017.02.22, 12:00 PM
In my experience, the F430 is one of the many bodies that tend to get wedged under the rails on RCP. The front splitter is a mixed blessing. Definitely makes the body more rigid/durable, but the aforementioned "wedge" issue can be frustrating during a race. Some people grind it off but then I'd want to reinforce the front inside of the body shell.

Are you sure you don't mean the 360gt body? I would have to look but I don't remember a front lip on f430 gt body.

TeeSquared
2017.02.22, 01:24 PM
Are you sure you don't mean the 360gt body? I would have to look but I don't remember a front lip on f430 gt body.

Hah, you are absolutely right! I've long since sold the body but I went and looked at a picture of it and compared it to a body guide and I absolutely had the F360, while all this while I thought it was the 430.

Shows what I know! Looks like the F430 would be the better choice.

AtomicCP
2017.02.22, 02:26 PM
Heres another question for you guys. I was reading some of EMU's posts and it sounds like 96mm setups are more stable than the 94mm setup im running. My JGTC GTR is tail heavy (thanks EMU!) so Im after a new body. I want a 94mm body and really like the F430 GT body. What body do you guys have for your 96mm setups? Would the F430 GT body be a good pick?

EMU
2017.02.22, 04:04 PM
96mm is good on 94mm bodies with longer rear ends, and 98mm bodies worth shorter rear ends. The 430gt has a relatively short rear end at 94mm, which I preferred to use in 94mm compared to 96mm. The rear felt a little light at 96mm.

94 bodies at 96, I like the f50, 360gtc, 2005/07 350z race... in general bodies that had a pushy feeling on throttle at 94mm. You could try the r34 gt and see how you like it at 96mm.

I feel that 96mm for me is better suited for sweeping layouts where 94mm better suited to point and shoot layouts where you want maximum traction exiting the corners. When you extend the wheelbase on 2wd mini-z, you ate essentially moving the weight ratio more towards the front wheels. Which gives more steering at the expense of rear traction with all other variables held constant.

tommy_greeneyes
2017.04.05, 02:47 PM
EMU knows the best. I 2nd to all his ideas

AtomicCP
2017.04.26, 03:54 PM
So after the last few races ive been changing things up little by little like EMU said. I tried running 96mm with the GTR and found it to be more stable but the guys hosting the race didnt like the fact that the wheels werent in the wheel arches. I started looking at the other faster guys and noticed most of them are running 98mm and a few had 102mm bodies. So after the mains I asked to demo one of their cars. I actually ran a faster lap than the owner with his 98mm 599xx! Needless to say Im going to retire the 94mm setup for abit and go with the 458 GT2 and run 98mm. Thank you everyone for the advise!!!

EMU
2017.04.27, 02:41 AM
Glad that you had some time to feel things out.

My solution to their complaint would be to make the wheel arches a little larger :p

98 with many current bodies offers good balance. Some tracks I like 94, when its more slower stop and go corners, and sweeping layouts 98.

AtomicCP
2017.04.28, 04:59 PM
I got the 458 gt2 body coming so now they cant say anything when I TQ! lol