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AustinMini
2006.03.09, 04:25 AM
Hi there,
I probebly got a noob question, I tried te search option.
what I can figure out is that the difference between RM and MM is the lengt of the wheel base so it can fit different body's.
Is this correct or am I missing something ??
RM is a longer wheelbase setup than MM.
Is there any other difference in performance ??? Let's say I'm running on a short technical track the MM setup would be better than RM wich works better on a track wit longer parts.

Tnx for the help
Grtz a total Noob

Blackranger3d
2006.03.09, 08:53 AM
Hi there,
I probebly got a noob question, I tried te search option.
what I can figure out is that the difference between RM and MM is the lengt of the wheel base so it can fit different body's.
Is this correct or am I missing something ??
RM is a longer wheelbase setup than MM.
Is there any other difference in performance ??? Let's say I'm running on a short technical track the MM setup would be better than RM wich works better on a track wit longer parts.

Tnx for the help
Grtz a total Noob


RM = rear mount
MM = Mid mount
This difines where the motor is in relation to the rear axil. So RM is mounted behind the axil and MM is mounted infront of the axil.


I think you missed the main difference, handling. From what I have read
MM is easier to control less tail swing harder to drift. It is less prone to oversteering (sliding)
RM is a bit harder to control and it drifts better

I only own an MM and I am fairly noobish myself so correct the above it is wrong.

AustinMini
2006.03.09, 09:02 AM
RM = rear mount
MM = Mid mount
This difines where the motor is in relation to the read axil. So RM is mounted behind the axil and MM is mounted infront of the axil.


I think you missed the main difference, handling. From what I have read
MM is easier to control less tail swing harder to drift. It is less prone to oversteering (sliding)
RM is a bit harder to control and it drifts better

I only own an MM and I am fairly noobish myself so correct the above it is wrong.

Tnx for the explination I got a firelap 2.0 And I can make both, at this moment it's MM.
Grtz

Spoon
2006.03.09, 09:08 AM
I have only driven MM so I can't comment on the handling but there are also length differences.

The RM bodies are 90mm and 94mm. I think you can also do 86mm, but there's not that many short bodies around.

The MM bodies are almost all 98mm. This includes the Enzo, Murcielago, McLaren, etc. There are some longer van bodies that will fit on a MR015 and MR02 but they don't handle very well at all.

There are also some exceptions, like the 94mm Mid Mount motor pods. It's an aftermarket motorpod that allows you to have Mid Mount handling with Rear Mount bodies (NSX, Supra, 350Z, Modena, Corvette, etc)

Just FYI, the AWD is 90mm or 94mm.

AustinMini
2006.03.09, 12:45 PM
Tnx this info from u all clearse alot up.

Grtz

EMU
2006.03.09, 12:54 PM
Spoon just about covered it.

RM bodies will tend to have more push under power (understeer) and more swing entering turns without power or braking.

MM bodies have tend to understeer less under power, and have a bit more turn in in neutral conditions.

Track conditions may give one setup more of an edge than another, but adjusting the setup to suit the track, both can be very competetive. An RM setup you can go into the turns a little faster let the rear swing around a little and hammer out of the apex. Most of my cars are setup MM. The current body that I race is a 575GTC RM body with an Atomic 94mm MM pod. I get alot of steering, which many drivers find too responsive. I like it because I can turn inside of almost any other car at the track.

There is only 1 86mm RM body, Lancia Stratos.

There are a few MM bodies that are longer than 98mm, the minivans. They can handle well when setup properly. The longer wheelbase makes them a little more stable despite the increase in center of gravity due to the body. I have a few custom bodies that are longer than the standard 98mm. I have a 106mm Jaguar XJ220 which must be driven similarly to an F1. It looks slow on the track due to its increased wheelbase, but puts up some good laptimes.

bolter9
2006.03.09, 12:56 PM
Handling depends on the type of track your running. On a low grip surface like concrete, RM generally tracks better because there is more weight behind the rear wheel, while MM spins out more. On a high traction surface like RCP, MM is easier to drive because the weight is more balanced- the weight transfers from side to side more immediately when going into and out of turns. RM tends to over steer a bit more and can require a bit more counter steer input from the driver.

Of course the hopups you're running will also effect handling, but this is the basic difference between weight distribution for RM and MM.

...from my experience anyway...

Spoon
2006.03.09, 02:14 PM
I have a 106mm Jaguar XJ220 which must be driven similarly to an F1. It looks slow on the track due to its increased wheelbase, but puts up some good laptimes.

That's a really good point about the F1's. Sometimes they look slow, but on my Mini-96, I get my fastest times from my F1. Probably a 5-10 second advantage over 50 laps.

Of course, that's when I can get my F1 to behave. Every once in a while, it just becomes undrivable.

jason barnes
2006.03.09, 02:40 PM
bolter 9 i totally agree with you .been racing since 2003 went to first nationals. we only had rm's then . the car this way is easyer to drive on any surface.........jb

MagicMan
2006.03.09, 06:30 PM
Hi there,
I probebly got a noob question, I tried te search option.
what I can figure out is that the difference between RM and MM is the lengt of the wheel base so it can fit different body's.
Is this correct or am I missing something ??
RM is a longer wheelbase setup than MM.
Is there any other difference in performance ??? Let's say I'm running on a short technical track the MM setup would be better than RM wich works better on a track wit longer parts.

Tnx for the help
Grtz a total Noob

I noticed you asked about fitting into different bodies.. there is a motor mount that they call the ML (multi-length) that allows for you to set it forth, or back. (adjusting for 94-98mm) And as a matter of fact, depending on the T/H plate that you use, you can adjust from 90-94mm as well. Getting this motor mount, will allow you to run your same chassis setup, in any body, weather it be 90, 94, 98. and as for some of you guys saying MM is generaly better... I find that incorrect, someone stated in this thread that it depends on the track surface... I believe it has more to do with track layout.. here is a video of an RM 90MM wheelbase on a RCP surface doing insane speed and handling, the board is not modified, just suspension/motor/tires, all the goodies. I'm driving in this video:

http://www.youtube.com/watch?v=7UphqeZ4Y58

now heres a 98MM 'Modified' car that has been fetted, even with the fets, and the extra stability from a MM, note that the lap times are if not 'even', possibly more than the RM.

http://www.youtube.com/watch?v=lHkxkwF5Zwc

so it totaly depends.

Well I hope I covered everything. HAPPY RCin'

The MagicMan

bolter9
2006.03.09, 06:55 PM
someone stated in this thread that it depends on the track surface... I believe it has more to do with track layout..

Ok I have to argue semantics here...

Layout doesn't have any affect on the way a car handles- rather the car's setup affects the way it handles on a given layout.

Now take that same layout and swap out the surfaces...slippery or traction- the same setup on the car will handle differently on both surfaces, same layout.

RM tracking better on a slipery layout (like concrete) is down to basic physics..more weight behind the drive axel- now obviously a specific car setup and driver's style can negate or accentuate a lot of that, but I'm making the point that you will notice a difference between RM and MM on different driving surfaces- and if that surface is on the slick side (concrete), the difference will be even more note worthy.

Naturally it's a matter of preference.

jason barnes
2006.03.09, 08:30 PM
hey magic man , looked at both video's . Isee what you mean . honda is nice gets the weight a little more forward. i run a Z8 body but our track is a little more slick . have i met you before . did you go to vegas . I would love to come and race with you . you drive good . ......jb

Mojar7070
2006.03.10, 10:31 AM
Magic: sometimes at a small track like that speed has a big disadvantage. You really have to perfect throttle control. There's so much power on the VDS car that you have to take the corners a little easier or you'll spin out, unlike the S2000, just the right amount of speed and power to get around the track smoothly. Which proves again speed is not everything. :)

Also, basement racing....awesome. Perfect layout for that space. Props to EMU for the great video taping. :D

jason barnes
2006.03.10, 11:05 AM
you are so right about corner speed .it is every thing in all racing.....jb

HammerZ
2006.03.10, 01:22 PM
Looking at the suspension between the RM cars and MM cars, the rear suspension that is. The RM with the motor hanging off the back is like a counterweight, this makes it feel stiffer even with a little longer T plate that should have more give in it. The MM cars even with the shorter plates and a stiffer upper shock spring (about 2-3mm longer than the RM spring is, for more preload), feels like a wet noodle. This brings us to the DPS (Disk Plate) or DDS (Disk Dampner) setups, seems more MM drivers swear by them as the RM guys is isn't that big a deal. This is just an observation at the suspensions alone, and not the weight bias of the two types.

bolter9
2006.03.10, 01:47 PM
Looking at the suspension between the RM cars and MM cars, the rear suspension that is. The RM with the motor hanging off the back is like a counterweight, this makes it feel stiffer even with a little longer T plate that should have more give in it. The MM cars even with the shorter plates and a stiffer upper shock spring (about 2-3mm longer than the RM spring is, for more preload), feels like a wet noodle. This brings us to the DPS (Disk Plate) or DDS (Disk Dampner) setups, seems more MM drivers swear by them as the RM guys is isn't that big a deal. This is just an observation at the suspensions alone, and not the weight bias of the two types.

interesting- I haven't tried the DPS yet (infact I"m running my MMs with out any top suspension at the moment).

I'd think that the extra weight in the rear of the MM would make the suspension feel looser, since it's making it flex more- with the motor pod being further away from the h-plate. Something about the weight of mass calculated over length (blah blah blah, I've been out of college for what, 10 rs?? :p )

HammerZ
2006.03.10, 01:56 PM
Yes, the rear axle is farther away from the plate on the MM cars. At least the MM cars dont have the motor hanging back there. This usually translates into the difference in traction. The MM drivers seem to be fighting a losing battle on that, as the RM drivers seem to have quite enough here. This is looking more at the up down movement, and not so much the side to side (roll). When it comes to the side to side, both are about the same.

bolter9
2006.03.10, 03:35 PM
Yes, the rear axle is farther away from the plate on the MM cars. At least the MM cars dont have the motor hanging back there. This usually translates into the difference in traction. The MM drivers seem to be fighting a losing battle on that, as the RM drivers seem to have quite enough here. This is looking more at the up down movement, and not so much the side to side (roll). When it comes to the side to side, both are about the same.


Good god, I meant RM in my last post. How am I supposed to propose my theories, if I can't get my abbreviations correct??? :p

On RM the motor is further away from the h-plate, which would make it a greater load for the suspension then MM- causing the suspension to travel more and feel "looser". However, the extra weight in the back of the RM gives it more traction. Which is why, IMO the RM tracks better (and tends to "chatter" more on high traction surfaces), but the side to side weight transfer is slower then MM, making the car feel heavier through the turns.

All in all, I prefer MM for RCP- because it's quicker through the weight transition, and you don't give up any traction (since the surface is not slippery).

HammerZ
2006.03.10, 05:02 PM
I have used Atomic grooved tires on the back of most of my cars. The only ones the 10 deg tires are best for is the MM cars, as it helps keep the back end in line. I have not had that same luck with the RM cars with 10 deg, it usually squirms under the extra load and the tires dont last long. Would not be as bad if the tires wore out even, Instead it looses chunks of rubber making it worse. The 20 or 30 deg tires work way better here. On some cars I used the Kyosho MT tires because of the larger tread blocks, to support the loading. After ripping up a few sets of tires, one learns what works and what don't.

I just like to think of the RM type as the 911 with it's rear weight bias. It's a good handling car as long as you keep that in mind, you forget that and it will hit the wall tail first. There is weight transfer, but in this case it loads all four wheels. Instead of coming off the rear to the front like the MM would. Also look at fighter jets, some of those are designed with the CG so far back on the wings that they shouldn't be able to fly. Only with the computer systems that they have to smooth out the flight pattern. They are designed like that to make them more agile in flight.

The MM, just pick your favorite mid engine supercar to relate to. They are known for smoother handling all around.

MagicMan
2006.03.10, 11:10 PM
Magic: sometimes at a small track like that speed has a big disadvantage. You really have to perfect throttle control. There's so much power on the VDS car that you have to take the corners a little easier or you'll spin out, unlike the S2000, just the right amount of speed and power to get around the track smoothly. Which proves again speed is not everything. :)

Also, basement racing....awesome. Perfect layout for that space. Props to EMU for the great video taping. :D


Very very true. it has a lot to do with throttle control, throttle has a great deal to do with how much you are allowing your car to steer, but this is all old news. See in small tracks like this, you may go lock to lock more than you'd like, but depending on how much throttle you give, it will control the size of the arc that you swing your car.

Someone made the comment that you will only notice differences of MM and RM on different surfaces, that is incorrect. You will notice differences of MM and RM on the SAME surface, that way you can directly relate how each car is handling on that surface. I never said the layout changes the way the car handles, I said a cars handling may be better on certain layouts, and I prefer tighter layouts, because hey, if your car can whip around my basement track flawlessly, well I can only imagine what it can do on any larger scale RCP.

hey magic man , looked at both video's . Isee what you mean . honda is nice gets the weight a little more forward. i run a Z8 body but our track is a little more slick . have i met you before . did you go to vegas . I would love to come and race with you . you drive good . ......jb

Jason, you are welcome anytime, you'll find my AIM/ICQ/YAHOO/MSN on here, contact me when you wish. I only race with people, I dont like going there alone. I'll pop in when EMU comes by with some of our other friends. It fits a comfortable 4 people, crouded 5 or 6. And for racing, 3-4 at a time. Let me know!

Your neighborhood magician!
The MagicMan

MagicMan
2006.03.10, 11:12 PM
Correction on my first post on this thread, the ML doesnt do 90mm. I'm sure many of you guys knew that, just wanted to make sure I corrected this before someone actually went out to try it.

1ofdfew323
2006.03.16, 10:39 AM
I have 01F chassis and 02MM chassis. I race the both on a very slippery surface ( kinda like the garage floor when its wet) not at the real track (foam). The 01F chassis (it's has an 02 RM set up) off the box it works great w/ no mods except for the front tires. I had to replace it w/ something that has less grip (30's) so I wont oversteer.

W/ my 02 MM I had to mount an extra AAA battery under the FORD GT body behind the taillights to put some weight in the back to eliminate the rear from spinning out. I am using low gears (7 pinion) so that I can have brakes and make that turn. Our track is about 20'x15'.

Foam racing my MM works great while my 01 starts hopping taking that corner (too much traction).

HammerZ
2006.03.16, 10:38 PM
Running on my laminate flooring at the house, it is very slick so I can spot chassis setups easy. My F40 MR01 did have the original mount and an old Powerline ball diff on it (the diff was junk) on it set for the low setting, even with that setting the rear did slip some in the turns. I had to use alot of countersteer to control it in every turn. I changed it to the MR01F style rear pod with an MR02 ball diff. After the change it is like a night and day difference in the way it drove. The rear is now glued to the floor in turns, and the car holds the line way better. Dropping the motor seems to make a big difference, The different ball diffs may have some effect as well as the Kyosho diff is smoother than the old Powerline I was running. The MR02MM is a radicaly different car handling wise, In this case a 10 deg tire in the rear is a big help. You keep the rear light it will not shread the tires.

imxlr8ed
2006.03.17, 11:31 AM
Finally got my Enzo hooked last night... MMs are so finicky, but when they work, they work well ! They seem very sensitive to compounds, as opposed to my RMs, which have the ability to run the tires down to nothing (I have some fronts that sit at the inner bead level of the wheel) and still perform predictably.

I am diggin' my Enzo right now though... hope the setup lasts longer than a week this time ! :D