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Old 03-01-2014, 08:44 AM   #13936
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Originally Posted by Dino_D View Post
Actually I don;t move my weight around, i just added enough so the front doesn't really lift on acceleration with the RM4. approx 42g, and re-tuned my shocks accordingly.
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You need to move the battery full forward and add anywhere from 30-45g of weight up front to keep the nose down, and you probably want to run 3 anti squat to give you as much off power steering as possible. We also use 10-15 drag brake to assist with steering. Remember our tracks are technical more point and shoot tracks.
moving the battery full forward and adding 45g of weight will take maybe 1-2% of your weight off the rear and put it on the front. I know that doesn't sound like a big amount, but it is huge in the way it feels on the track. trust me, i've spent the last year chasing weight distributions on my mid motor car to get it to where it is. i can guarantee you changed your car much more than you think by doing that.

i agree with what you say about wanting a neutral car, but i just don't agree with how you go about it. 4 gear in any motor configuration will shift the weight around way too much to feel neutral. the car naturally wants to understeer on power and oversteer off power with a 4 gear transmission, and anything you do on top of that to mask that natural tendency will just ruin another aspect of your cars handling. it's like building a house on a swamp. you might be able to do it, but you'll make so many compromises that what you end up with is something barely passable as a house.

you are much better off to start out with something that is by nature more neutral feeling. 3 gear counteracts that weight shift to produce a much more neutral driving feel, and you don't need to do goofy things with your car to mask the excessive weight transfer.

with that said, if you're not getting enough rear grip with an rm3 configuration, you're probably not doing something right. rm3 with a battery shoved the whole way back should give you so much traction that you don't know what to do with it.
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Last edited by RC10Nick; 03-01-2014 at 09:09 AM.
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Old 03-01-2014, 10:57 AM   #13937
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His setup was running on slicks. If you've got more grip, you'll flip. Hey, that rhymes!

I honestly don't know how his car drives but just by looking at his setup sheet I can tell I'd hate it. First, and this is a HUGE red flag to me, if the front shocks have more total piston hole area and the front oil weight is higher than the rear, it's crap. This is a very VERY common mistake. Even most pros make it. It is the result of a misunderstanding of how pack relates to piston speed and shock length.

He is clearly trying to run a very low roll center in the front with a higher roll center in the rear. He is running a shorty battery all the way back. With more weight rearwards, he is going to need more roll stiffness but there is a neat phenomenon with the greater front nose kick of 2wd cars that once you get too soft in the suspension, the front will unload on power out of corners no matter what. For carpet, grip isn't lacking. You are proving that with traction rolling.

I'd shift the battery all the way forwards and change to MM3. Run 0 rear kick. Move the front outer hole camber link location to #2. Leave the back alone. Reverse his pistons front to rear. You want the larger holes in back. Adjust the oil accordingly. You will need to balance the spring rates and shock oils. See the tuning with camber links thread for info. Reduce the front caster to 20 degrees. I have no idea why anyone would ever run 30 degrees except on loose dirt with inline steering. That's the only time.
That should get you closer but you'll still need to fine tune things.
Thanks for the feedback the 20 caster really helped, i didnt get to try anything else because of a broken rear tower, the 0 antisquat would work better with the mm3 wouldnt it rather than mm4 also what oil should i run in the diff i have 2k in it but it feels lighter than the balldiff should i be around 5k?

Last edited by thefan; 03-01-2014 at 01:36 PM.
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Old 03-02-2014, 01:02 AM   #13938
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Hey guys instead of buying another buggy whats involved in making my V1 a V2
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Old 03-02-2014, 02:27 AM   #13939
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Originally Posted by KarlB View Post
Hey guys instead of buying another buggy whats involved in making my V1 a V2
The +8mm chassis, new side pods, front/rear arms, shock towers, front shock bodies/shafts and LRC RR suspension mount would be the main performance changing things that I can think of.
There are also a few type B parts that offer more tuning, easier maintenance or durability increases too.
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Old 03-02-2014, 09:01 AM   #13940
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Anyone know the part numbers for the new +8 aluminum chassis and side pods? I cant find them any where

Thanks
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Old 03-02-2014, 10:02 AM   #13941
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Originally Posted by RC10Nick View Post
moving the battery full forward and adding 45g of weight will take maybe 1-2% of your weight off the rear and put it on the front. I know that doesn't sound like a big amount, but it is huge in the way it feels on the track. trust me, i've spent the last year chasing weight distributions on my mid motor car to get it to where it is. i can guarantee you changed your car much more than you think by doing that.
You have more grip at your track. Hence you can run mid motor. I am sure if we had a track with more grip, I would have used another setup by now. Most US style tracks have been treated so you have more grip than normal. I am speaking about dirt tracks or untreated clay tracks. We have no where the same amount of grip.

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i agree with what you say about wanting a neutral car, but i just don't agree with how you go about it. 4 gear in any motor configuration will shift the weight around way too much to feel neutral. the car naturally wants to understeer on power and oversteer off power with a 4 gear transmission, and anything you do on top of that to mask that natural tendency will just ruin another aspect of your cars handling. it's like building a house on a swamp. you might be able to do it, but you'll make so many compromises that what you end up with is something barely passable as a house.
The entire field of other competitors all use RM3 (22 2.0, B5) and we can can out accelerate them everywhere. On low grip, what you stated, "understeer a bit on power", is good, as I am able to get on power harder and not feather the throttle or roll on the throttle, off-power I have steering without needing to tap brake to make the car turn while the rest of the field needs to transfer weight forward to turn.

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you are much better off to start out with something that is by nature more neutral feeling. 3 gear counteracts that weight shift to produce a much more neutral driving feel, and you don't need to do goofy things with your car to mask the excessive weight transfer.
We had sponsored durango driver drive his RM3 setup vs my RM4 setup at our track and he was consistently 0.4s faster per lap than his setup. And "Yes" he was like saying that RM4 and the plastic chassis won't work till he drove my car. Its cause he didn't take the time to develop it, and worked around RM3 instead.

We can discuss setup theories all day, but in the end, its the performance on track that counts. I do understand what you are saying, but different tracks call for different setups.
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Old 03-02-2014, 10:48 AM   #13942
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Originally Posted by ekt View Post
The +8mm chassis, new side pods, front/rear arms, shock towers, front shock bodies/shafts and LRC RR suspension mount would be the main performance changing things that I can think of.
There are also a few type B parts that offer more tuning, easier maintenance or durability increases too.
I must have missed it, what did they change in the shocks? Longer? Shorter?
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Old 03-02-2014, 11:03 AM   #13943
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I must have missed it, what did they change in the shocks? Longer? Shorter?
They are shorter, they will have 21,5mm stroke, instead of 23mm on the V1!
When you download the V2 manual and go to page 40, you can see the typo on the shockbody,
Allso it looks like there are some low profil spring retainers on the V2 aswell!?
I think it is because of the strait front arms and for the lower rear shock tower?
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Old 03-02-2014, 11:09 AM   #13944
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Anyone know the part numbers for the new +8 aluminum chassis and side pods? I cant find them any where

Thanks
Manual sayes..
+8 chassis - 320240
Side posts - 320215

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Old 03-02-2014, 12:52 PM   #13945
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Originally Posted by Dino_D View Post
You have more grip at your track. Hence you can run mid motor. I am sure if we had a track with more grip, I would have used another setup by now. Most US style tracks have been treated so you have more grip than normal. I am speaking about dirt tracks or untreated clay tracks. We have no where the same amount of grip.
you don't need more grip to run mid motor. i've said that a bunch of times already. it's a complete fallacy. you need the right weight distribution. that's all you need. if you've got the right amount of weight where it needs to be, your car will work. my mid motor car has the weight distribution of a rear motor car. it works on med grip clay. it works on blown out 1/8th scale tracks. it works in the gravel behind my house. it works everywhere people have told me a mid motor car would not work. please do not say one more time I run mid motor because i have more grip. that is simply not the case.
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Old 03-03-2014, 09:35 AM   #13946
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While I agree with you that you can successfully run MM on pretty much any track, there could be times that I personally wouldn't. If I ever found a place where I had to run MM4 to make MM work, I wouldn't. I'd go back to RM3. I don't like the way any 4 gear setup drives. 3 gear drives so much more neutral than 4 gear does.

His setup is certainly unique. I'm not going to call it wrong. It's different. What I see isn't a person who is trying to increase rear grip but rather keeping it while increasing front grip off power. I'm not going to call it wrong since it works for him and he obviously likes it. It's not how I personally would do things but there isn't only one way to do things.
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Old 03-03-2014, 10:21 AM   #13947
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FWIW, Travis Amezcua TQ'd and won the ChiTown Shootout with a DEX210V2 this past weekend. Lutz came in 2nd. Travis ran RM, Lutz ran MM. Both were insanely quick, but Lutz got the hero lap award by over half a second. Two super cool factory drivers as well, very friendly and helpful to anyone who asked or wanted to talk.
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Old 03-03-2014, 10:27 AM   #13948
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Doesn't MM4 have the same torque vectors as RM3? (Can I say torque vectors?) what I mean to say here is that with MM4 when you mass the throttle the weight transfers to the rear because of the torque of the car. Same as RM3 right?

In my experience if you run MM3 you won't have much control over the car in the air and it may also be more difficult to roll over whoops and rhythm sections. It does drive pretty neutral though. Very flat.

I ran MM3 for a while and never liked how flat the car was, this is was where the RM3 cars seemed to have an advantage. Once I switch to MM4 I was able to rocket out of the corners just like most RM3 cars. I usually run a little bit of anti squat to keep from popping the front up with a wheelie.
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Old 03-03-2014, 10:53 AM   #13949
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Doesn't MM4 have the same torque vectors as RM3? (Can I say torque vectors?) what I mean to say here is that with MM4 when you mass the throttle the weight transfers to the rear because of the torque of the car. Same as RM3 right?

In my experience if you run MM3 you won't have much control over the car in the air and it may also be more difficult to roll over whoops and rhythm sections. It does drive pretty neutral though. Very flat.

I ran MM3 for a while and never liked how flat the car was, this is was where the RM3 cars seemed to have an advantage. Once I switch to MM4 I was able to rocket out of the corners just like most RM3 cars. I usually run a little bit of anti squat to keep from popping the front up with a wheelie.
4 gear drives like a 4 gear and 3 like a 3. Motor placement doesn't change that. The reason why you probably liked MM4 better than MM3 out of corners has everything to do with weight transfer. You didn't have enough weight on the rear wheels in MM to get good traction. MM4 artificially transfers that weight rearward and you got grip. The main problem could have been corrected with weight and antisquat settings. MM4 is the solution if you don't understand static weight balance or antisquat. Once you do understand these, MM4 suddenly seems like a compromise rather than an answer.
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Old 03-03-2014, 03:21 PM   #13950
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What would you guys use for gearing on a outdoor track with about a 90ft straight. Its my dads car and it will have a traxxas velenion motor in it, so no boost or anything. It has the stock spur as well, Thanks.
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