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MPP compression rod and control arm bearings.

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Why there is not more conversation in regards to what really improves the handling of the car astounds me.

The compression rod bearing and lower control arm bushing take it to a whole new level. Now that i have most of the MPP components available (and UPP swaybars) you can really connect with the tires and grip. Turn in control was severely lacking, and my assumption is under hard braking and aggressive turning, I would wildly lose alignment as the tires fought the g forces of heavy braking...talk about reduction of understeer and putting it on rails.

Performance cars should not have bushings with NVH considerations as the main goal.
Solidifying the main components seeing the anger of your braking and launching will drastically improve your times on an autocross track...i put my money on it.

I need to see a time attack with a factory M3P and then with only MPP control arms(better bushings) compression rod bearings and control arm bearings....no coilovers or braking upgrades.
 
@SFLM3P19 I'm with you on giving up a little NVH as needed to really sharpen up the handling and responsiveness! Since I got this car I've been saying I'd happily make that tradeoff, and so far I've replaced 6 rubber bushings/mounts with spherical bearings to follow through on it. :)

Yeah not a ton of handling upgrades talk happening here right now. There's lots in the archives though, try Google search using site:teslamotorsclub.com as well as the in-forum search.

Since ye asked for more suspension mods talk, ye shall receive! :D This morning I did a first quick twisty road run since installing Redwood Öhlins DFV Performance Sport coilovers + Redwood pillowball top hats + MPP FLCA bearings + MPP compression rod inserts + getting the car aligned. I had already replaced the Uberturbines+PZ4 with 245/45R18 300TW Bridgestone Potenza Sport on 18x8.5" Titan7 T-S5 forged wheels. Ride height at all 4 corners is matched to this car's stock height at the rear. (Going low is not for me or my wife or the places we drive.) Dampers set about 2/3rds stiff, I haven't tried other damper settings yet. (The DFV have one adjustment knob for compression + rebound.)

As background, around here most low-traffic twisty roads have lots of very tight turns and nasty ill-maintained pavement. They can be a challenge for suspension control beyond just cornering forces. Racecar stiff and low is not right for them. Nor is too soft though. The stock suspension was a mess if you got going real fast (still within limits of stock M3P grip), the car would get real floaty and bouncy and the weight would keep shifting all over the place out of sync with the actual road and driver inputs.

(There are smooth, well-paved twisty roads too of course, but most of them are either much higher traffic, or a bit of a detour from my regular driving, or they have homes / businesses / etc and are completely inappropriate for fast driving. I'll test the new suspension through some smoother, higher speed twisties when I have a chance though.)

The best way I can sum up the new setup is...drama-free. It's firm and sporty yet not harsh at all, smooths out rough stuff much better than stock suspension. It feels always stable and in control, like nothing can upset the car now (short of impacts where you stop and look for damage after). The wheels follow the road, the weight stays on the wheels, the reactions stay prompt, and everything just flows. The car moves with the road as needed but never more than needed. You feel the road but it's not beating you up about it. Even when I went fast over a big dip where the M3P ran out of rear suspension travel, it somehow oozed almost gently into the bump stops, and then rebounded promptly + accurately without any further effects. Felt in control and much smoother than stock. With the stock suspension if you go fast over a dip like that the car would slam really hard into the bump stops, and then struggle to regain composure afterwards.

Ride quality with the pillowballs and dampers at about 2/3rds stiff is comparable to stock on better roads, and better than stock on bad roads. The worse the pavement and the faster you drive over it, the bigger the ride quality improvement. The ride is a little different though, for sure you can tell the it's firmer, especially at low speeds over mildly messy neighborhood roads, but it's more controlled without the stock bounciness, so overall the ride feels at least as good to me, and often better. About the only time the stock suspension rode better was when going slow over rough bumps or roads. At a certain range of slow speeds this suspension just moves the whole car up and down to follow, whereas the stock suspension would smooth things out a bit more with its bounciness/springiness.

My opinion of the ride does reflect my preference for firm control over any hint of bounce or float. If you want your car to glide over the road and really filter it out like a good air suspension then the "Performance Sport" coilover kit and spherical bearing top hats aren't what you want. ;) Based on this setup I would guess Redwood's GT kit + stock top hats can ride real smooth, and still be a big handling upgrade thanks to vastly better damping than stock. (*sugar* probably a bottle of quality olive oil would dampen better than stock.) I've read the GT spring rates are significantly softer than Performance Sport, and the dampers are tuned to match of course. The Performance Sport setup is what I want for my M3P but I'm pretty curious now how the GT kit feels.

Note everything above is just trying to compare the suspension mods vs stock suspension. If you include the upgraded wheel+tire setup my car for sure rides better than 100% stock, but that's not a fair comparison. However I did make a conscious decision to pair taller sidewalls (245/45R18) with the firm "performance sport" coilover kit. I think the result is much more to my liking than rubberband tires + softer suspension. Also picking tires with very sturdy sidewalls helps. The Potenza Sport (300TW) feel more sturdy than anything I've used with more than 250TW. (I'm not tracking this car, so I've no reason to go below 300TW or so.)

I'll try turning down the damper stiffness soon and see how that affects ride + handling. If there's any notable street handling limitation still remaining, I'd say it's the Model 3's lack of suspension travel, especially in the rear as best I can tell. A stock M3P seems challenged for travel and clearance, and I haven't made any changes that improve those aspects. Though Redwood says this kit is good for a small lift if you want...

Hopefully in the next week or two I'll end up on some longer twisty road runs. This was just a few miles for some quick fun and to make sure everything feels okay before my wife needs the car for a longer outing (involving a lot more twisty road miles).
 
A few other notes:

Turn-in and steering responses are of course way way better. I'm sure both the coilovers and the FLCA bearings helped this in their own ways. I've still got lots of rubber bushings left so you're not going to confuse it for a literal race car, but it's much sharper now and I'm happy with it.

If I understand the Redwood coilovers instructions correctly, I could safely add 15mm more rear suspension travel than how they're currently setup, because I'm running stock ride height, but I had trouble adjusting the free length. I'm totally new to coilovers, still figuring some things out. :) I'll revisit this at some point. That one big dip where I hit the rear bumps stops I would hit them on the stock suspension too, and I didn't feel bump stops anywhere else, so I'm not worried about lost suspension travel. But if there's more travel to be safely gained, without risking the battery too much, then of course I want it.

I've zero plans to ever track this car, but I do have a bit of HPDE experience from years past so I'll try to extrapolate what this setup might feel like. Basically, I think if you do primarily street driving with occasional track days (that was me with my last ICE car), this Performance Sport kit would be just right. However if your car is more of a weekend warrior seeing a lot of track time, and especially if you're running track-focused wheels+tires+alignment, then a stiffer setup would certainly be worthwhile. Redwood has a Race/HPDE version of this kit for off-the-shelf simplicity + affordability, that's probably what I would get if I was still keeping the car streetable but with more track focus. (Beyond that I'll just drool over custom suspension setups based around actual racecar level dampers... 🤤)
 
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I love the solid compression arm bushings and LCA bushing on the track and autocross. I seem to be in the minority, but my street love is TBD. I had the ball joints on the compression arm start clunking on rebound (cracks in the concrete) shortly after install, so I replaced them too. I blamed it on the torn rubber OEM bushings that I drove around on last winter, but I'm starting to notice the clunk coming back again after 4-5 months. The product description says there will be NVH and they say long term durability has not been evaluated so they're completely up front about it.
 
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stock compression rod to MPP inserts must be an improvement....

but the compression rod bearing upgrade is insane. That was a single item install along with an alignment and brake lines.

the immediate increase in feel and handling shot me into the moon, i kid you not, this factory compression rod bushing is the issue with tracking a model 3.
because there is no tracking of the tires when in factory form... this play is causing huge discrepancies in driver input and applicable traction.
 
The best way I can sum up the new setup is...drama-free. It's firm and sporty yet not harsh at all, smooths out rough stuff much better than stock suspension. It feels always stable and in control, like nothing can upset the car now (short of impacts where you stop and look for damage after). The wheels follow the road, the weight stays on the wheels, the reactions stay prompt, and everything just flows. The car moves with the road as needed but never more than needed. You feel the road but it's not beating you up about it. Even when I went fast over a big dip where the M3P ran out of rear suspension travel, it somehow oozed almost gently into the bump stops, and then rebounded promptly + accurately without any further effects. Felt in control and much smoother than stock. With the stock suspension if you go fast over a dip like that the car would slam really hard into the bump stops, and then struggle to regain composure afterwards.

This is good to know about the Ohlins dampers. I'm after the same experience, thanks for the feedback.

However I did make a conscious decision to pair taller sidewalls (245/45R18) with the firm "performance sport" coilover kit. I think the result is much more to my liking than rubberband tires + softer suspension. Also picking tires with very sturdy sidewalls helps. The Potenza Sport (300TW) feel more sturdy than anything I've used with more than 250TW. (I'm not tracking this car, so I've no reason to go below 300TW or so.)

Interesting you also went with Bridgestone Potenza Sport tyres. I need new tyres soon and was looking at the same ones to replace the Pilot Sport 4 that came with the car. Glad to know you like them. Tossing up between the Goodyear Eagle F1 Asymmetric 5, Pilot Sport 5, Pirelli P Zero PZ4 and the Bridgestone Potenza Sport.
 
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@decryption The PZ4 that came on my M3P were pretty lackluster for a modern max performance category tire. Worse grip dry and wet than the Potenza Sport, and the PZ4 squealed a lot in hard driving.

The OE PZ4 were better than a non-performance tire, don't get me wrong, but I'd try any of the other tires you listed before getting PZ4 again. I didn't hate them but there's clearly better options.
 
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@decryption The PZ4 that came on my M3P were pretty lackluster for a modern max performance category tire. Worse grip dry and wet than the Potenza Sport, and the PZ4 squealed a lot in hard driving.

The OE PZ4 were better than a non-performance tire, don't get me wrong, but I'd try any of the other tires you listed before getting PZ4 again. I didn't hate them but there's clearly better options.
I'll mention I changed from the OE PZ4 to Potenza Sport at about 1k miles on the car, because I needed to downsize the wheels. So my comparison is actually based on fresh vs fresh tires, not worn-out old ones. Different sizes on different wheels, but 245mm vs 235mm is a pretty minimal difference, I think I'd be hard pressed to tell any grip difference just from that alone (if comparing the same tire).

It did take me a few days to get past the new tire grease on the Potenza Sports, so my grip comparisons are not literally back-to-back same day, but once the Potenza Sports wore in the extra grip wet and dry was obvious. So was the lack of squealing vs the PZ4.
 
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MPP compression rod bearing is like one of the best kept secret. If you drive the car on track or at the edge of traction, you'll appreciate what it does. It adds no NVH for me on street tires but when on track with 305 Supercar 3R tires, you can feel the night and day difference. The best way to describe it is that it magically adds more front end grip to the car.
 
what its really doing is removing the play in the OEM compression rod bushings....(and allowing further Caster adjustability which helps camber control with the wheel turned)

The handling of these cars and most Non-Track oriented cars is impeded by the main goal of isolating and removing NVH from entering the passenger compartment. If you put rubber in a joint or bushing, that toe/camber/FUCA/trailing/Compression arm is going to move during hard acceleration, braking and high gforce maneuvers.


What I noticed in the M3P, even after upgrading the lower control arm bushing, FUCA, and coilovers, was the still extreme amount of understeer...which I hypothesized was an issue with losing my alignment under hard braking(you can feel it in the steering wheel and in the brake pedal)
the location of the compression rod makes me think it sees extreme "compression" under braking, causing the tesla to shove through any demanding turns, toed way out, with the inability to regain traction until the gforces and body roll relax allowing the bushing to reabsorb the compression forces and realign itself.....
no control into, through, or out of the turn if your trying to get that power back down, without giving the chassis time to settle...




no more rubber isolation, direct road feel, mechanically stiffened alignment just means those motors are actually pushing you in the right direction, instead of multiple..
 
what its really doing is removing the play in the OEM compression rod bushings....(and allowing further Caster adjustability which helps camber control with the wheel turned)

The handling of these cars and most Non-Track oriented cars is impeded by the main goal of isolating and removing NVH from entering the passenger compartment. If you put rubber in a joint or bushing, that toe/camber/FUCA/trailing/Compression arm is going to move during hard acceleration, braking and high gforce maneuvers.


What I noticed in the M3P, even after upgrading the lower control arm bushing, FUCA, and coilovers, was the still extreme amount of understeer...which I hypothesized was an issue with losing my alignment under hard braking(you can feel it in the steering wheel and in the brake pedal)
the location of the compression rod makes me think it sees extreme "compression" under braking, causing the tesla to shove through any demanding turns, toed way out, with the inability to regain traction until the gforces and body roll relax allowing the bushing to reabsorb the compression forces and realign itself.....
no control into, through, or out of the turn if your trying to get that power back down, without giving the chassis time to settle...




no more rubber isolation, direct road feel, mechanically stiffened alignment just means those motors are actually pushing you in the right direction, instead of multiple..
Have you compared the bushing to the insert from MPP?
 
Have you compared the bushing to the insert from MPP?

The first thing we did when we finished designing and machining the inserts was test them in the press against the stock bushing without inserts. You can see a significant improvement of up to 75% deflection reduction at 1500lbs. The MPP.R bearings have essentially 0mm of deflection, so you can see that the jump from stock>inserts is more significant than inserts>bearings.

That being said, for a track car, the bearings make the most sense.

1654015343019.png

1654015348210.png


If anyone has questions, let us know!
 
The first thing we did when we finished designing and machining the inserts was test them in the press against the stock bushing without inserts. You can see a significant improvement of up to 75% deflection reduction at 1500lbs. The MPP.R bearings have essentially 0mm of deflection, so you can see that the jump from stock>inserts is more significant than inserts>bearings.

That being said, for a track car, the bearings make the most sense.

View attachment 810981
View attachment 810982

If anyone has questions, let us know!
Well worth not dealing with increased NVH and having the simplicity of the inserts installation compared to the complete bearing for my purposes.

Thanks!

Have you ever considered comparing this to the old redneck PU injection method?
 
An observation. If you buy replacement compression arms from eBay or Rock Auto, the slots in the bushing are solid. There’s a molded relief but not nearly like the OEM part, no daylight passes through. Perhaps just a poor job at Chinese reverse engineering. They might flex less? Of course the rubber could be a different compound and the opposite would be true. I don’t think the inserts would fit in these.
32A1DEE9-A193-403A-A7B1-7949DE7636CF.jpeg
 
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An observation. If you buy replacement compression arms from eBay or Rock Auto, the slots in the bushing are solid. There’s a molded relief but not nearly like the OEM part, no daylight passes through. Perhaps just a poor job at Chinese reverse engineering. They might flex less? Of course the rubber could be a different compound and the opposite would be true. I don’t think the inserts would fit in these.
View attachment 811033
The oem ones can have that too when new! It is usually just a very thin layer across the hole that you could poke a hole through easily. Who knows though, maybe they are more durable than the OEM bushings.