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Old 02-26-2014, 09:03 AM   #13876
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Actually even though the oil is heavier in the front, the rear has more static damping than the front on my cars. Even when I drop it from 1-2 feet it lands evenly, same distance 3mm before bottoming, same speed on compression, not the front or back sinking down first.

There are many ways to achieve the same static feel. Heavy oil, big holes and lots of holes, thinner oils with smaller holes. Also you can achieve the same pack with a variety of combinations. Many ways to skin a cat
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Old 02-26-2014, 09:16 AM   #13877
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I also wonder if the volume of the shock makes a difference in the amount of pack for a given oil and piston combo.
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Old 02-26-2014, 09:19 AM   #13878
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http://www.tribology-abc.com/calculators/damper.htm

This seems to point to volume being a key component in static dampening and squeeze velocity. It also seems to make sense from my days in engineering school.
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Old 02-26-2014, 10:33 AM   #13879
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Piston speed through the oil in conjunction with hole size and quantity determines pack. Obviously viscosity plays a small role as well. A shock with a longer stroke will have greater pack than a shock with a shorter stroke with the same piston. Static dampening is irrelevant to this. Yes you can get the same static dampening with a different piston/oil combination but the pack will not be equivalent.
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Old 02-26-2014, 11:38 AM   #13880
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awesome Vince. Glad to have you. I'll let you know about my testing after this weekend.

I realized later you probably still had your alumů..I ran that quite a bit on the small track and it was pretty wicked. I run mid motor as most of my favorite tracks here in SoCal are clay and high bite. We run slicks sometimes. Or Barcodes, and Ions. So you get the idea of what kinda of surface it is. OCRC from the Reedy race is one of my tracks. I've even run the original chassis at OCRC and with a good balanced setup (see fredswain! ) it's pretty dialed. I'm also running a shorty pack.

Are you also mid motor?
I am not mid motor. Currently RM3 with a shorty pack. RM is all I've ever known -- always wanted to try mid motor but could use a pretty reliable setup as a base. I guess you could say that grip at our track is pretty good so MM may work for me.

In a nutshell could you give me a quick sell on MM, how does it drive? Could you point me in the right direction? If my current setup doesn't work this weekend I'll most def try MM. THX.
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Old 02-26-2014, 11:41 AM   #13881
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I think we might be saying the same things essentially. More stroke has to equal more volume. Can't go deeper unless it's bigger. More volume equals more pack then right? if everything else was constant. I think that's the same as saying a longer stroke will have greater pack. I could have this messed up….I work with DSP and audio mostly these days!
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Old 02-26-2014, 11:50 AM   #13882
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I think we might be saying the same things essentially. More stroke has to equal more volume. Can't go deeper unless it's bigger. More volume equals more pack then right? if everything else was constant. I think that's the same as saying a longer stroke will have greater pack. I could have this messed upů.I work with DSP and audio mostly these days!
Volume in itself isn't going to change pack. Lets say you use a front shock that has the normal piston and shock shaft but has a larger rear shock body. Same total stroke but different shock volume. Obviously it would need a new tower but that's irrelevant. This shock has the exact same pack as the standard short shock even though the volume is different. I believe you are referring to the actual amount of oil that the piston itself travels through so in that regards yes a longer stroke would move through a larger volume of oil. I mention this as travel or stroke length so as not to confuse things.
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Old 02-26-2014, 12:09 PM   #13883
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I am not mid motor. Currently RM3 with a shorty pack. RM is all I've ever known -- always wanted to try mid motor but could use a pretty reliable setup as a base. I guess you could say that grip at our track is pretty good so MM may work for me.

In a nutshell could you give me a quick sell on MM, how does it drive? Could you point me in the right direction? If my current setup doesn't work this weekend I'll most def try MM. THX.
MM works well on a HIGH grip track clay, astro or carpet track. Normally it offers better handling on a fast flowing track. It tends to push slightly more on hairpin turns so getting a good fast line with a higher corner speed is essential. Remember MM carry more corner speed better. Depends on the layout of your track.

RM cars can run on anything from low to high grip. If your track doesn't have the grip level, then I wouldn't even bother with it. I ain't saying you can't get a MM to work on med grip, but its just harder to get the power down vs the RM setups.
RM work better in a point and shoot technical track, as the rear weight helps the car turn around and plant the car better out of turns. Remember Phend won a national race with a RM car vs a field of MM cars.

People normally say RM4 is for only low grip, but we still use RM4 on med to high, as I can have the throttle pinned on exit instead of rolling on the throttle with a RM3. Plus as the track starts to dry, the car is less effected by the conditions and level of grip.

Guys with MM tend add weight in the rear or near the rear axles. Guys with RM add weight in the front. LOL.
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Old 02-26-2014, 12:14 PM   #13884
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@Vince: Happy to share my MM setup, let me know if I have missed something. It's a little complex….forgive the length here!

MM4 with Shorty Pack all the way back. Speed control in front. This was done because I wanted to run a fan on my speedo and it didn't fit very well with the speed control behind the shorty pack. (I actually have it the other way now…always testing!) However this setup was pretty dialed. The car really seems to come alive with shorty packs. So much lighter and you can move the weight around much more. Then I put my spectrum micro receiver and capacitor on opposite sides. They are very similar in weight so I have very equal left right weight distribution. I have pics if you want.

Front:
25 wt 1.3x6
Avid Red Springs
-1 Degree of Camber (sometimes 2 when I traction roll too often)
Middle Hole on Shock Tower
Outer Hole on Suspension Arm
Camber link outer hole on hub/inner hole on tower

Rear:
25wt - 1.3x6 pistons
Avid White Springs
-1 Degree of Camber
Camber Link inner hole on bulkhead/outermost hole on hub
Exotek LRC Quick Change Rear Front Suspension block 3deg toe in/0 anti squat
Exotek LRC Rear Hanger
Rear hubs 0 degrees of toe in.

I arrived at this setup after working through the swain method of balancing. I want to get more springs and try again so I can have a few different sets of balanced springs front to rear.

This is the best setup I've created so far for MM4, however I wouldn't say it's perfect by any means. I don't usually recommend MM3 typically for dirt/clay type US tracks. You don't get the throttle induced weight transfer that really helps when jumping and accelerating because the motor's torque will NOT cause the car to shift as much. The car won't shift to the rear when you accelerate and you don't get the brake induced nose down action on big air jumps or in corners either. Essentially the car drives flatter with MM3. This might work in very very high traction situations in which you don't need the weight transfer for traction.

I hope that helps. I'm sure FredSwain and Dino can jump in here too
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Last edited by 13Maschine; 02-26-2014 at 12:59 PM. Reason: adding camber settings
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Old 02-26-2014, 12:22 PM   #13885
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Quote:
Originally Posted by fredswain View Post
Volume in itself isn't going to change pack. Lets say you use a front shock that has the normal piston and shock shaft but has a larger rear shock body. Same total stroke but different shock volume. Obviously it would need a new tower but that's irrelevant. This shock has the exact same pack as the standard short shock even though the volume is different. I believe you are referring to the actual amount of oil that the piston itself travels through so in that regards yes a longer stroke would move through a larger volume of oil. I mention this as travel or stroke length so as not to confuse things.
totally right Fred!! Would anyone ever want to run a short shaft in a big shock?

I was thinking this way as it seems most equations for calculating these types of forces and velocities seem to be based on volume AND stroke. I need to dig up some more of these and study them though. I've only just started to dig back into the heavy differential equation and fluid dynamics portion of this. Seems pretty deep.
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Last edited by 13Maschine; 02-26-2014 at 12:24 PM. Reason: clarity
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Old 02-26-2014, 12:31 PM   #13886
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Originally Posted by 13Maschine View Post
This is the best setup I've created so far for MM4, however I wouldn't say it's perfect by any means. I don't usually recommend MM3 typically for dirt/clay type US tracks. You don't get the throttle induced weight transfer that really helps when jumping and accelerating because the motor's torque will NOT cause the car to shift as much. The car won't shift to the rear when you accelerate and you don't get the brake induced nose down action on big air jumps or in corners either. Essentially the car drives flatter with MM3. This might work in very very high traction situations in which you don't need the weight transfer for traction.

I hope that helps. I'm sure FredSwain and Dino can jump in here too
Your setup looks good. We don't get the grip levels here. I live in the great white north. Much colder, so we need more GRIP. Plus most of our dirt/clay tracks are either low to mid. Even carpet tracks are med-high at best.

Did you know a lot of the touring car drivers are having either the same oil weight front and rear or using slightly heavier in the rear now? They say it makes the car more stable and easier to drive. The lighter front end gives more low speed steering while not making high speed overly sensitive.
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Old 02-26-2014, 12:57 PM   #13887
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Thanks Dino

Interesting….I may pickup a touring car again next year as we also have a pretty decent outdoor track and a few indoor tracks here in california.

My setup feels pretty good, I'm able to use a little brake on the hairpins when needed and it has a lot of forward bite so I can usually mash on the throttle pretty hard. Many times I'm wheeling so I have to be careful and sometimes when this happens too much I will add some ant squat. Usually when I start to wheely I need more steering anyway so this helps there too.

Right now I have the +11 chassis from RDRP and my ESC in back with the shorty in front. It seems too long the bench, I'm guessing there is a magic ratio of wheelbase to width. We'll see after testing.
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Old 02-26-2014, 01:12 PM   #13888
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Thanks everyone for helping me out here.
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Old 02-26-2014, 01:19 PM   #13889
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No worries, let us know how you make out!
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Old 02-26-2014, 05:07 PM   #13890
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Interesting….I may pickup a touring car again next year as we also have a pretty decent outdoor track and a few indoor tracks here in california.

My setup feels pretty good, I'm able to use a little brake on the hairpins when needed and it has a lot of forward bite so I can usually mash on the throttle pretty hard. Many times I'm wheeling so I have to be careful and sometimes when this happens too much I will add some ant squat. Usually when I start to wheely I need more steering anyway so this helps there too.

Right now I have the +11 chassis from RDRP and my ESC in back with the shorty in front. It seems too long the bench, I'm guessing there is a magic ratio of wheelbase to width. We'll see after testing.
Well originally I am a touring car guy. And you know how we are with setups. I really wished most of the tracks here didn't convert to off-road.
Let me tell you when I first did off-road a few years ago - what an eye opener. LOL. I was quick thru the flat sections till the jumps. Then it was cart wheels and landing on my roof. Took me a while to get the knack of it. Off-road is so 3D.. LOL. Touring is 2D

Actually I can't wait to try the new DETC coming soon.

Oh the Avid springs are great. They are more linear than the original durango springs and better suited to indoor tracks. Cause with progressives, they get harder on compression, so mid way thru a corner, the spring gets harder and my car starts to push on a low speed turn.

On big fast flowing tracks, I use progressives. But its track dependent and also how you like the car to react. You just need to find a setting that matches your driving style.

Also on the 210, the nose is pretty light, so I normally put like 30-42g of weight to keep the nose down and give me more steering on power.

+8 is pretty good a most places (indoor and outdoors). +11 is nice on a wide open outdoor track. Its also good if you want to reduce your steering and gain more stability on bumpy tracks.
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