I had an MR-015 once for about a week. At the time I had too many cars to keep them all running so I promptly sold it. One of the guys from the local racing crew came up with the idea of running a classic car enduro which basically limited us to the following list of cars.
Ferrari 250 GTO
Ferrari 246GT Dino
Porsche 934 RSR Turbo
Porsche 935 Turbo
Shelby Cobra 427SC
Shelby Cobra Daytona Coupe
Skyline GT-R KPGC10
Lamborghini Jota SVR
Lamborghini Countach LP400
Lotus Europa Special
Toyota Trueno AE86
See a trend here? All very narrow, rear motor mount, short bodies. My current chassis are setup for a mid motor mount and a longer wheelbase. I really wanted to have a car for this enduro and figured this was the chance to start tuning a whole new car. Typically the way I would do this is to drive the car stock for a little while, install some basic upgrades and then see where I needed to go. I sort of skipped the first step and installed the motor that we were going to be using for the enduro race. I also installed bearings in the car. This essentially gave me a "fast" stock car.
First I tried the Trueno which rolled like a barrel coming out of corners, I thought the lower Countach (LP 400) would be better but I could roll that one pretty easily as well out of the faster corners. The Countach was much better but it still needed some work to become race ready.
The biggest issue I faced was the body roll. I guess the higher center of gravity (because of the stacked batteries) was causing the car to lean a lot more than I was used to. First I used a couple of shims to lower the front of the car and I also installed a ball differential. I actually don't think the ball diff is necessary but I thought it might help dissipate just a little bit of power through the corners and help keep the car planted. You can certainly get by without a ball diff, I just happened to have one on another car I could try out. The shims were a significant improvement.
The next thing I decided to go with was stiff springs up front. I also installed the proper offset wheels for the LP400. I had 0mm offset narrow on the front and 0mm offset wide on the rear but the LP400 comes with +1 narrow for the front. I had some dish wheels sitting around that fit the +1 offset and those made a world of difference. The next time I took the car onto the track I had to try really really hard to flip it over. Right now it tracks really well, is very nimble through corners and should make a very competitive racer.
I still have a couple of adjustments to make to my car before I feel it is race ready. First an alloy motor mount, for several reasons:
I also need to pick up a carbon H-plate since I don't think a stock plate would last the entire race.
- Rear mount cars tend to have an issue with cracked motor clips,
- The motor is running very hot right now and I think an open mount would help that and
- It's easier to get a decent gear mesh with all pinion combinations with an alloy motor mount.
Overall I find the MR-015 to be very agile when set up with a short (90mm) body. I think it will perform well with the track layout we have for the enduro, I just have to remember to carve the corners a little bit and I should be able to keep all four wheels on the ground. As a stock racer I think an MR-015 could be a great car. You just have to consider that the center of gravity is slightly higher than the flagship MR-02. With some attention to driving style and some simple hopups the MR-015 makes for a very nimble racer.