miataturbo.net-like debauchery thread (about the ND or something)
#2603
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But any shaft speed on rebound is set by the spring right? I can see how deeper in the stroke the wheel will want to return faster. I totally get that how sharp or tall a bump is will cause compression speeds to change, but it can only return as fast as the spring pushes it back down. You only get a certain amount pushing down once you crest the bump.
Dont mean to derail too much here. This is obviously a very focused thread. Just more research on my end needed I suppose. Growing up riding dirt bikes I'm quite used to 3 ways. Now you got me thinking about 4 ways
Dont mean to derail too much here. This is obviously a very focused thread. Just more research on my end needed I suppose. Growing up riding dirt bikes I'm quite used to 3 ways. Now you got me thinking about 4 ways
#2604
I'm a software guy, not an ME, but here's my understanding. Think about what happens over the bump. The wheel moves up, some of that motion translates into compressing the spring, some into moving the body upwards. Since the body weighs a lot more than the wheel, most goes into the spring.
Now the wheel crests the bump, and the wheel is no longer moving up. The energy in the spring pushes the body and wheel away from each other, with the wheel moving a lot faster because it's lighter.
So yes, the wheel will only go down at fast as the spring and gravity will pull it, but that's plenty fast enough to make a difference in driver vs road induced rebound because it is light compared to the body.
--Ian
Now the wheel crests the bump, and the wheel is no longer moving up. The energy in the spring pushes the body and wheel away from each other, with the wheel moving a lot faster because it's lighter.
So yes, the wheel will only go down at fast as the spring and gravity will pull it, but that's plenty fast enough to make a difference in driver vs road induced rebound because it is light compared to the body.
--Ian
#2608
high speed rebound adjustments are pretty much useless in my opinion. Maybe an F1 team can find gains using them, but for the average consumer it just adds confusion, cost and another hole for the damper fluid to leak out of.
I played with some of these (4 way adjustable mountain bike shocks) for days and couldn't really tell wtf the high-speed rebound was doing. Smart to leave it off the shock IMO.
I played with some of these (4 way adjustable mountain bike shocks) for days and couldn't really tell wtf the high-speed rebound was doing. Smart to leave it off the shock IMO.
#2609
high speed rebound adjustments are pretty much useless in my opinion. Maybe an F1 team can find gains using them, but for the average consumer it just adds confusion, cost and another hole for the damper fluid to leak out of.
I played with some of these (4 way adjustable mountain bike shocks) for days and couldn't really tell wtf the high-speed rebound was doing. Smart to leave it off the shock IMO.
I played with some of these (4 way adjustable mountain bike shocks) for days and couldn't really tell wtf the high-speed rebound was doing. Smart to leave it off the shock IMO.
to deal with them without requiring further adjustments. Driver input and road surface are out of the picture. In off road suspensions, high speed rebound can be tuned to change how the vehicle performs near full droop. I see that high speed rebound adjustment employed in rally cars and off road trucks/buggies.
NA/NB and also ND Xidas for example, have digressive pistons that bleed off most of the high speed rebound. This allows an adjustable low speed segment where driver input, roll moment (grip) and vehicle weight are highly variable and
often require tuning. The high speed portion is tuned by yours truly with a range of wheel assemblies. On a vehicle with much heavier wheels/tires, less or no digression is needed. On the NA/NB at least (low unspuing mass), the only way to get the suspension to work without digression is to have too little low speed rebound so that the entire rebound side is weak. This has the added benefit of being able to pressure balance more easily and also reduces hysteresis. Problem is handling ultimately suffers with race tires when there is inadequate low speed rebound so we don't do it. Typically, we'll focus on a typical track setup but also test a super light and also heavier wheel setup just to make sure we don't uncover any anomalous behavior. The Tecna's for example, have been carefully dialed to work with OEM weight wheels/tires but still cope with the now standard 225/45/15 EHP on 15x9 6UL. At the relatively low price point they're targeted for, that has proven a challenge. Many prototype valving sets rejected.
So yeah, decisions made for function reasons, not cost or bling factor.
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#2610
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The Tecna's for example, have been carefully dialed to work with OEM weight wheels/tires but still cope with the now standard 225/45/15 EHP on 15x9 6UL. At the relatively low price point they're targeted for, that has proven a challenge. Many prototype valving sets rejected.
#2613
That has always been the case, never stated otherwise. We just don't publish ETA, price, spec or anything else. We'll announce them when they are in stock and ready to ship. I only mentioned here to illustrate how that particular area of the damping curve receives specific attention in relation to it's intended usage.
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#2619
Anyone have reliable lap times that ND's are running? Actually being driven to the limit on 200tw tires? I'm curious how they stack up, and haven't seen any at our tracks around here yet. If so, mods list would be helpful.
Has the ECU intrusion/limitations during constant track use been permanently dealt with? I've been following this thread pretty close for the last year and don't recall updates on these items.
Has the ECU intrusion/limitations during constant track use been permanently dealt with? I've been following this thread pretty close for the last year and don't recall updates on these items.
#2620
Anyone have reliable lap times that ND's are running? Actually being driven to the limit on 200tw tires? I'm curious how they stack up, and haven't seen any at our tracks around here yet. If so, mods list would be helpful.
Has the ECU intrusion/limitations during constant track use been permanently dealt with? I've been following this thread pretty close for the last year and don't recall updates on these items.
Has the ECU intrusion/limitations during constant track use been permanently dealt with? I've been following this thread pretty close for the last year and don't recall updates on these items.
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