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Old 11-22-2011, 03:01 PM
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jmackani
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Originally Posted by MantisWorx
you guys are forgetting one MAJOR issue and that is spring force. on a 3500lb truck with springs that relate to over 1000lbs of force of course you will need more damping on the rebound to compensate for that, our tenth scale springs are nowhere near that type of force therefore, it simply is not the same our springs do not "Spring back" near as quick or with as much force as a 1:1 car. and most of the 1:1 cars use progressive springs and valving that also controls the fluid rates on the inside, we dont have that luxury.divide everything by 10 and see what happens. and once again guys try them first and THEN come back and comment, right now you are all just quoting paragraphs with no real experience. i have actually tried it during testing and it simply doesnt work as well as quicker rebound and this holds true even to this day. i am currently tuning my dex210, there is a washboard section on the back corner and with my 4 hole 1.1/1.2 20wt combo in the rear it keeps bucking the rear up and is not stable at all where as on my SC i can literally punch through it and gain positions over anyone who is not running the pistons. so i opened up the lower holes to 1.3 went down to 17.5 fluid and it now floats through like its supposed to! so in effect what did i do, i quicken up both but i quicken up the rebound more. i will say that yes if your rebound is too fast it can definately be counter productive there is no argument there. if you look at the video on my homepage there is a shot of the buggy going down the straight from the rear, it actually has too much rebound.
http://www.youtube.com/user/Mantiswo.../4/vGop6ZpNMQ8
there is another shot of the car coming straight towards you and on that shot i slowed the rebound down via smaller rebound holes and you will notice on that shot the the car floats. so right there we have some proof of what the effects are.
another video on my channel shows a 1.0/1.1 combo
http://www.youtube.com/user/Mantiswo.../3/E3P-0GBUaRs
this was during some prototype testing and these pistons were designed for a smoother track. as you can tell the truck bounces around ALOT it was controllable but with the slower rebound all you see is air under the tires and that means less traction!

on this video the truck weighs more and has 1.1/1.2 holes with looser piston clearances and 25/20 oil as you can tell the truck is much smoother and has much more traction in all aspects. the truck on this video is over a second quicker per lap(1.7 on fast lap) than the other video my avg time was better than the quick time on the other vid.
http://www.youtube.com/user/Mantiswo.../0/MjlWBzWNjkE

so you guys that want to test slower rebound please take some vid its much easier to see whats going on than to just talk about it!
I have a set of your pistons on order, but just an observation to note. The third video difference in time may be more than just the shocks working though. The track appears to have more moisture in it.
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