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PowerFlex Street Inserts Review (both)

green_henry

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#21
I installed both sides (yellow/street) before I had an AP and didn't mind the additional NVH, which was very mild. However, since adding an AP and a stage 2 tune a few weeks ago, I definitely notice more noise and vibrations. I've also had a Mountune RMM installed from almost day 1.

The noise and vibrations are more noticeable now than when I originally installed them, so I assume the mounts need to be re-torqued (no big deal for the passenger side, but a PITA for the driver side) :(
 


OP
HBEcoBeaST

HBEcoBeaST

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Thread Starter #22
Honestly I think the biggest help for torque steer was to install new OEM mounts along with these inserts. My old PSMM I could move around freely with my hand although the bolt was perfectly in tact. It never leaked fluid to my knowledge, but I'd consider it as 'failed' with the amount of play it had.

I didn't find removing the battery box or ecm as taxing for the trans side, but it was a bit more work than simply removing the headlight and popping out the overflow tank for the PSMM. I'm working with a crappy slow pump jack which was my biggest hold up. Definitely need to invest in a quick pump.

I will honestly admit I failed at installing the new PSMM upgraded bolt. I could not, for the life of me, remove the bolt on the new (or old) factory PSMM. I didn't want to use PB blaster or strip anything so I'll just keep the OEM bolt in until it breaks.
 


Spork1569

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Fillmore, CA
#23
Honestly I think the biggest help for torque steer was to install new OEM mounts along with these inserts. My old PSMM I could move around freely with my hand although the bolt was perfectly in tact. It never leaked fluid to my knowledge, but I'd consider it as 'failed' with the amount of play it had.

I didn't find removing the battery box or ecm as taxing for the trans side, but it was a bit more work than simply removing the headlight and popping out the overflow tank for the PSMM. I'm working with a crappy slow pump jack which was my biggest hold up. Definitely need to invest in a quick pump.

I will honestly admit I failed at installing the new PSMM upgraded bolt. I could not, for the life of me, remove the bolt on the new (or old) factory PSMM. I didn't want to use PB blaster or strip anything so I'll just keep the OEM bolt in until it breaks.
Same experience. I planned on installing an ARP upgraded bolt but couldn't for the life of me remove it. Now it's a spare if and when it breaks
 


Dpro

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Los Feliz (In the City of Angels) aka Los Angeles
#24
I have all of those bits. Maybe because the side mounts were the last of these modifications I didn’t notice the difference. I hear you on the movement contribution to TS, but I’d think it’s secondary to the inherent issue with the FWD cars. I’d expect the side mounts to be more of a factor in weight transference in the turns, reducing inertia and power loss in track outs.
You can doubt it all you want I do not have a front brace and my car is custom tuned and I immediately noticed the difference. It did minimize TQ steer to the point that its barely noticeable.
Oh and I do have a RMM installed and my stock side mounts only hve 6K on them.,
 


TyphoonFiST

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Rich-fizzield
#25
Still waiting on the Viton o-ring to come out so I don't have to deal with the one supplied coming apart.
 


TyphoonFiST

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#29
Well the cat is out of the bag....contact powerflex people! The updated o-ring is ready!



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Last edited:

Clint Beastwood

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#30
I have a set of these sitting around, haven't had a chance to install. I need to figure out how to tell if my stock mounts have gone to poop yet, I'd hate to get these installed and find out that the stock mounts are shot. Flooring it on uneven pavement *does* make me jump to the side, and it does tramline kinda bad on ribbed pavement.
 


OP
HBEcoBeaST

HBEcoBeaST

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Thread Starter #32
I have a set of these sitting around, haven't had a chance to install. I need to figure out how to tell if my stock mounts have gone to poop yet, I'd hate to get these installed and find out that the stock mounts are shot. Flooring it on uneven pavement *does* make me jump to the side, and it does tramline kinda bad on ribbed pavement.
My psmm was making a creaking noise on cold mornings. Kept checking the bolt but it was fine. After removing it I could easily move the top plate with my hands. I was experiencing worsening torque steer. Didn't realize how bad it actually was until I fixed it.🙄

The trans mount I could wiggle a little easier than the new OEM mount, but nothing close to the psmm level of movement.

I got a set of oem mounts for less than $90 shipped. Much easier and cleaner to install the inserts on new mounts. Plus once you remove the old mounts, you just pop the new ones in.

They help torque steer immensely but tramlining is usually more of a tire thing. Tiny wide tires follow grooves in the road, plus our quick, sensitive steering doesn't help either. I'd say the inserts improved tramlining, but nowhere near the amount they fixed tq steer.
 


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Denver
#33
I've thought of that also....But I'm anal like that....hell ll even contact them also just to follow up! Just wrote them currently to see if I can get an answer!
Yellow zip-tie looks and works great. I have driven the PSMM insert with both zip-tie and o-ring for one year. The o-ring looks like it's about to go, and the zip-tie looks new. With the zip-tie being yellow you will barely notice it.
 


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Denver
#34
I have a set of these sitting around, haven't had a chance to install. I need to figure out how to tell if my stock mounts have gone to poop yet, I'd hate to get these installed and find out that the stock mounts are shot. Flooring it on uneven pavement *does* make me jump to the side, and it does tramline kinda bad on ribbed pavement.
How many miles do you have on your car. If you below 10k I would think your current mounts are good.
 


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Location
Wichita
#37
I installed mine on friday with the APR bolt. I agree with everyone about how connected the car feels but so far I have to say that the noise is terrible! I have a little bit of added vibrations but that's not my issue, now I can feel the engine through the whole car. Best way I can describe it would be to say it is like a humming sound through all gears and speeds that does not diminish. I though it was cool for about 10 minutes then not so much. I know low frequencies travel and since the engine is more firmly mounted to the frame, those frequencies will reverberate through the whole car.....I just hope it gets a little better because a long trip might make me go insane.
I'm in the same boat with you. I'm curious on the disparity of comments. Can there be that big of a difference between street and race? I have a lot of general drone in addition to vibrations. There has to be a genuine difference somewhere, because this cannot be as simple as preferences.

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HBEcoBeaST

HBEcoBeaST

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Thread Starter #38
I'm in the same boat with you. I'm curious on the disparity of comments. Can there be that big of a difference between street and race? I have a lot of general drone in addition to vibrations. There has to be a genuine difference somewhere, because this cannot be as simple as preferences.

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I actually hear the mounts more than I feel them. The difference between street and race is most likely pretty significant. Race bushings are usually a step lower than solid metal IME. Which means vibrations.
 


Clint Beastwood

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#39
How many miles do you have on your car. If you below 10k I would think your current mounts are good.
19,998 right now. The engine squeaks and I can jiggle it a bit by hand. Took to the dealership and requested they check the mounts but they said they’re fine. I’m noticing a hum on decel in first gear. Might just buy new mounts and install them if the dealer won’t.
 




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