Clunk fix prototype testing: MSP/MP3 Rear Suspension
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so, how much stiffer is the ride? I find the car borderline too stiff now over my roads.
OH, and my fingers are still crossed, but the 156E's have been on since Nov. and nothing yet.
...on another note, it's really nice to see the community coming through with yet another great MSP product. Great job!
OH, and my fingers are still crossed, but the 156E's have been on since Nov. and nothing yet.
...on another note, it's really nice to see the community coming through with yet another great MSP product. Great job!
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70
Nice keep up the work and testing...
I've been interested in the progress of this for a while now.
I'm wondering if this will solve the AWR bar clunk issue some others have had...
I've been interested in the progress of this for a while now.
I'm wondering if this will solve the AWR bar clunk issue some others have had...
edstein: Silicone spray MAY work to reduce the front swaybar "squawronk" noise, but will have no effect on The Clunk in the rear (has been described as anywhere from "a clunking noise" to "a bowling ball rolling around in the trunk". Mine was somewhere in between. Some have had some luck by removing the bushings and wrapping the bar in teflon tape, works for ~ 150 miles (check the various clunk threads) but The Clunk comes back. What helps is to understand why...
The Physics of The Clunk: Mazda's swaybar bushings are placed too close to the center of the car. This allows the bar to both act in torsion (rotation), which is good, but also allows the bar to bend, which is bad. For a mental picture, take a pen and bend the pocket clip out at a 90 degree angle. Hold the pen right at the base of the clip, and rotate the pen by pushing on the end of the clip. See how the pen only rotates? Now hold the pen near the center of the pen. See how, no matter how tightly you hold the pen, it wants to both rotate AND "bend"? This bending motion does 2 things: 1) It wears out the bushings faster and 2) it places wierd stresses on the pan of the car and between the bushings. Nobody has proven quite where The Clunk comes from, but it disappears with tighter/firmer bushings (for how long nobody knows) and with bushing relocation. Racing Beat apparently had a kit on their race cars but hasn't offered it for sale (there are pics in other clunk threads), Delsing will come to market shortly with their kit, which I'm testing. While we won't have 4000+ miles of testing on the Delsing kit, it logically corrects the underlying issue, which should result in longer-term improvement.
Newf my man! Glad to see you again. The initial kit was very stiff, but initial installation was done with 19mm ribbed bushings which over-clamped the 20mm bar and added resistance to the suspension. Felt good, but a tad too stiff. The zerked (greasable) bushings I have on now give a much more supple ride (darned near stock) on anything from "regular" to moderate roads. On "perhaps I shouldn't take a new car here" bumpy roads (way bumpy) the roll stiffness is more noticable, but not objectionable. In harder cornering, especially sustained "off-ramp" type corners with mid-corner dips or bumps, the rear stays better planted. I was getting a little "hitch" in the "set" that the car takes when cornering in those scenarios; that's gone now and I'm noticing this on 205/55/16 Semperit Sport Grip tires (snow-optimized). I'm planning on putting the 17's on this weekend (if the snow forecast cooperates, we're getting 4-8" right now!) and giving another impression. I'll also reinstall the stock setup afterwards to "back to back" them. Pray for good weather!
The Physics of The Clunk: Mazda's swaybar bushings are placed too close to the center of the car. This allows the bar to both act in torsion (rotation), which is good, but also allows the bar to bend, which is bad. For a mental picture, take a pen and bend the pocket clip out at a 90 degree angle. Hold the pen right at the base of the clip, and rotate the pen by pushing on the end of the clip. See how the pen only rotates? Now hold the pen near the center of the pen. See how, no matter how tightly you hold the pen, it wants to both rotate AND "bend"? This bending motion does 2 things: 1) It wears out the bushings faster and 2) it places wierd stresses on the pan of the car and between the bushings. Nobody has proven quite where The Clunk comes from, but it disappears with tighter/firmer bushings (for how long nobody knows) and with bushing relocation. Racing Beat apparently had a kit on their race cars but hasn't offered it for sale (there are pics in other clunk threads), Delsing will come to market shortly with their kit, which I'm testing. While we won't have 4000+ miles of testing on the Delsing kit, it logically corrects the underlying issue, which should result in longer-term improvement.
Newf my man! Glad to see you again. The initial kit was very stiff, but initial installation was done with 19mm ribbed bushings which over-clamped the 20mm bar and added resistance to the suspension. Felt good, but a tad too stiff. The zerked (greasable) bushings I have on now give a much more supple ride (darned near stock) on anything from "regular" to moderate roads. On "perhaps I shouldn't take a new car here" bumpy roads (way bumpy) the roll stiffness is more noticable, but not objectionable. In harder cornering, especially sustained "off-ramp" type corners with mid-corner dips or bumps, the rear stays better planted. I was getting a little "hitch" in the "set" that the car takes when cornering in those scenarios; that's gone now and I'm noticing this on 205/55/16 Semperit Sport Grip tires (snow-optimized). I'm planning on putting the 17's on this weekend (if the snow forecast cooperates, we're getting 4-8" right now!) and giving another impression. I'll also reinstall the stock setup afterwards to "back to back" them. Pray for good weather!
Admittedly still low mileage on the kit, but a unique opportunity last night to drive on soundless roads... you know how quiet it is to drive on very fresh snow? It gives an opportunity to hear every OTHER noise the car makes when tire/road noise is filtered out... I could hear the trans, gearing, and engine but even on a wavy road where the rear clunk was clearly heard in the past there was NO NOISE at all from the rear suspension (good news). And we're due for 6+ inches more snow tonight in my area of NJ. Well, Delsing wanted foul weather testing...! 
...and if I see ONE more thread with entries from our Southern brethren saying "Snow? What snow? My MSP is FINE in the winter..."... AARGH! I want my 17's back on! I have this nice set of '03.5's... with 170 miles on 'em... none of them mine...:mad:
...and if I see ONE more thread with entries from our Southern brethren saying "Snow? What snow? My MSP is FINE in the winter..."... AARGH! I want my 17's back on! I have this nice set of '03.5's... with 170 miles on 'em... none of them mine...:mad:
Delsing's working up some brackets to use the E bushings and I'm testing them next. Different prackets are required to mount the bushings on this kit vs. what Mazda used because Mazda chose to mount the bar on a non-flat section of bodypan. It's no big deal (check pics), but Mazdas bushings are also a different width than aftermarket.
Given Mazda's bushing history, though (let's see, they started with "A"...), I'd almost rather go with good name-brand aftermarket! We'll test 'em see how they work out.
I threw the 17's on yesterday and unfortunately have a "tire pull" (must've put a front on the rear, doh!) so I'm correcting that tonight before driving the 17's too hard. What I could tell on the morning commute was same as before only slightly more so and more immediate. (better rear firmness and predictability but not harsh, no clunk). Also these RE040's really pick up the road grit! My SNOW tires are quieter.
Given Mazda's bushing history, though (let's see, they started with "A"...), I'd almost rather go with good name-brand aftermarket! We'll test 'em see how they work out.
I threw the 17's on yesterday and unfortunately have a "tire pull" (must've put a front on the rear, doh!) so I'm correcting that tonight before driving the 17's too hard. What I could tell on the morning commute was same as before only slightly more so and more immediate. (better rear firmness and predictability but not harsh, no clunk). Also these RE040's really pick up the road grit! My SNOW tires are quieter.
'03.5 wheels on, update!
UPDATE: I corrected the tire pull (front to rear rotation on one side and I'm straight again) and this thing is FUN!.
With the 17's on the difference in stiffness is noticable, but mild. I can especially see it when pulling into my driveway at a diagonal as the back tire lifts slightly MORE off the ground than before. The ride is not obnoxious - no additional "head toss" on rough roads, but that rear end stays where it's supposed to be under heavy cornering, and trailing throttle can bring that rear end out just enough.
3 weeks of rough roads and salt, sand, sun, rain, and the kit is still clunk free and no squeaks. It's DIRTY under there, but that's to be expected. I cribbed a shot of the type of bushings currently being tested, and took a dirty shot of the suspension as it sits now. I included a gratuitous beefcake shot of the MSP with the 03.5 wheels on it... because I could.
Here are a few shots to help picture this whole thing...
UPDATE: I corrected the tire pull (front to rear rotation on one side and I'm straight again) and this thing is FUN!.
With the 17's on the difference in stiffness is noticable, but mild. I can especially see it when pulling into my driveway at a diagonal as the back tire lifts slightly MORE off the ground than before. The ride is not obnoxious - no additional "head toss" on rough roads, but that rear end stays where it's supposed to be under heavy cornering, and trailing throttle can bring that rear end out just enough.
3 weeks of rough roads and salt, sand, sun, rain, and the kit is still clunk free and no squeaks. It's DIRTY under there, but that's to be expected. I cribbed a shot of the type of bushings currently being tested, and took a dirty shot of the suspension as it sits now. I included a gratuitous beefcake shot of the MSP with the 03.5 wheels on it... because I could.
Here are a few shots to help picture this whole thing...
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- '03.5 Blazin' MSP (sold) ................. '14 Soul 6 GT
Ping, I'm glad the whole tire deal (swop) worked out for us. I put your tires on this past wknd and WOWWW! It was so great driving with the performance tires again. Now I need the suspension you are testing! I now have the fogs, in-line sunroof, and a 20% tinted strip at the top of my windshield. AWESOME BABY(first)
367 (mp3yellow
367 (mp3yellow
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Laser03pro
Member
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- 1995 Miata
Hurry up n release it my friend needs one bad in his MP3 lol im sick of it just riding with him sometimes.
Heh, my MSP just started clunking, and all I've got to say is...do you need a southeastern tester? 
It's a good thing MSPs come with a halfway decent stereo, 'cause I think I'd go crazy if I had to listen to that everytime I drove my car. Eagerly awaiting updates .
It's a good thing MSPs come with a halfway decent stereo, 'cause I think I'd go crazy if I had to listen to that everytime I drove my car. Eagerly awaiting updates .Will be following this closely. I really like the way the bushing with the zerk fitting is working out.
FWIW, at 12,500 miles, I've still not heard the clunk, and the front "squonk" is gone now with warmer weather. It was about 85 deg. and sunny all weekend here in the lovely South...
FWIW, at 12,500 miles, I've still not heard the clunk, and the front "squonk" is gone now with warmer weather. It was about 85 deg. and sunny all weekend here in the lovely South...
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DooMer_MP3
Member
My 156Es have failed, and I really would like to get this new kit. How much longer til it comes out?
Chris
Chris
I'll email Dave again and he'll also probably post when ready. Original goal was soon and very soon... but he wants to make sure these are exactly right before releasing them. I'm also putting zerked reds on next weekend to see what the difference will be. The zerked blacks (Summit Racing 13/16, Energy Suspension urethane) were great, unobtrusive, no squeaks or problems. One very interesting part of this kit is that it allows some semblance of corner weighting - the bar is adjustable (within a narrow range) up and down on each side if you use the right (larger) bushings. This is good if it's adjusted right, but can make the car do weird things if the corner weighting isn't right. On mine I messed around some and found that if the bar isn't installed "loose" and then tightened while the car's on a level surface the sway bar becomes an auxiliary spring in the rear - to use smaller words: "makes the car pull a little". The effect is more noticable on the 17's or larger wheels as the slip angle is smaller and the effect is magnified. Once leveled out, though, everything straightens, the clunk stays away, and the rear end feels more, well, controllable and predictable. It's a subtle thing, not like slapping on a 1/4" larger sway bar but more like tightening up the shocks just a touch.
More as we get it, stand by...I don't think it'll be long but I can't wait either!
-L
More as we get it, stand by...I don't think it'll be long but I can't wait either!
-L
DooMer_MP3
Member
So are you saying when the time comes, the parts should be installed on jackstands, but torqued to spec while on the ground (suspension loaded)? Just a bit confused. Thanks for the response!
Chris
Chris
