Powerflex vs. FunctionFirst transmission insert

Hey all, Anyone have any experience with Powerflex vs. FunctionFirst transmission inserts for a manual? Quite a big price difference in the two - specifically looking at the yellow street inserts (already have 964RS semi solid engine mounts). FF sell theirs for $135 PowerFlex are $40... ​​​​​ Could possibly use black rather than yellow too. But for new looking for feedback on price difference and build quality. I think they are the only two brands available? Thanks ​​​​​​ ​​​​​

Hey Dan, I tried a FF black, but removed it right way as NVH was nasty. Sounded like mount was broken off. Race car, no problem.

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Thanks JTT that bad really?? I've got semi solid engine mounts so I don't mind MHV but if its going to sound broken maybe yellow are the way to go...

I installed the orange FF, and had to remove it due to the NVH. Believe me, even the orange version transmit every clunk on shifting and the transmission gear noise gets into the cabin.

Dan, there is an extensive thread on mounts and mods HERE But my experience was that there was no way I could live with it on the street. Really did feel like something was broken. Alarming to the point I immediately went home and went back under car thinking I forgot to tighten the bolts.

Yikes! Thanks all Have you gone with yellow or just standard? Thinking I'll go a pair of powerflex yellow at $70AUD including postage they are 1/3 of th​​​​​e FF cost.

I have the FF yellow installed and love them. I really gives another level of road feel back to the car. The 996s feel great, but these parts nudge the feeling toward the 964 level (in my opinion). This was a desirable NVH change for me. I got the parts used, so the price was in between.

Thanks - hard to justify the FF price tag also thanks for that link JTT very helpful

I've got the FF black trans mount inserts in mine... It is louder/more NVH, but it's not that bad - certainly doesn't sound "broken". I recently picked up a pair of the yellow Powerflex inserts and a new mount bushing. When I change the bushing out I'm going to change the inserts as well.

How recently was your transmission mount replaced? The reason I ask is that you might be better off with replacing the entire bushing with a firmer one. Rennline has a good one that I used on my 2000. With the right tool, you don�t even need to drop the transmission out to replace it.

I put in the Powerflex yellow about 6 months ago. I like it just fine. Nothing too bad about the NVH with the insert and semi-solid engine mounts.

I designed 3D printed polyurethane inserts with a view to selling them; due to being 3D printed they can be made semi-hollow and tuned more for the street rather than the cast solid ones available today. Unfortunately the print times are long to make them; so I wouldn't be able to price them a lot lower than what is on the market today so I didn't think it was worth it. I can post some pics later if people want to see. I also made 3D printed solid polyurethane anti roll bar bushings and tested them on my car. They work great!

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Please do!

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+1 I'd like to see the pictures.

Thanks everyone, @dporto why did you choose the powerflex ones over FF? If they were comparible in price I'd probably go FF but at half the cost the powerflex seem like they are the same but a better price?

I installed the FF black inserts first (and I didn't pay full price for them - I think I paid around $100). I decided to use them because my mount at the time was in bad shape, and I didn't have the tool to change it. I figured the hardest ones would be best due to the nature of the existing mount. I've since bought a new mount/bushing and I figured I'd change to the yellow (PowerFlex) inserts both because the bushing will be new and hopefully the yellow inserts will reduce the NVH a little bit while still stiffening the stock mount.

Thanks everyone, the powerflex look much the same as the FF so I think ill just go with those in the yellow spec. Like the idea of black but I know it wont be a good move haha

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Here you go, the roll bar bushings are solid polyurethane, the tranny mount insert is not. You can see how I designed it to have an initial easy flex to stop vibration during idle and cruise but when you put your foot down and a lot of torque is delivered they compress up to a point then get more solid. I never actually got around to fitting a set on my car and I wasn't sure anyone would want to buy them as a kit.

Weird the other pic didn't come thru

^^ Those ^^ look pretty cool Chris... Maybe best of both worlds. Maybe price them between the PF and FF points if it covers your cost with a reasonable profit...

Very interesting. I wonder how long that material (foam?) will hold up?

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The material (the white parts) is thermoplastic polyurethane, so essentially the same material as the cast (orange) parts. Its very strong, even trying to trim any stringy bits of leftover plastic with a razor is hard with it. I've had my 3D printed poly roll bar bushings on the car for around 5k miles now and no problems. For the tranny insert the material is under a compression load so the best case for longevity.

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Yeah I might look at this again soon, I need to give my printer a service etc and replace some worn parts and then run the numbers on the cost of raw materials Vs what I can sell them for plus labor time and figure out if its worth it. The last couple of months I spent some time on another project which is a bit off topic here (although I do carry one in my car for protection). I designed the worlds first 3D printed taser and sell all the files to make them at my website for $16, pics and movies on this page on my website: http://3dziio.com/IMG.html I thought about listing this in the for sale section on rennlist; but I'm unsure if it violates the rules here as its not porsche?

I was trying to figure out what your "roll" bar bushing was. It looks to be a "sway" bar bushing. If so there r several different diameters depending on the application. If u do sell them u will want to include that info.

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Let me know if you move forward on the trans insert.

If you are getting one, get the powerflex. No reason to overpay for a piece of plastic.

Seems pretty oversimplified, but maybe it is that simple? Functionally speaking, are the two products the same durometer/shore hardness? Are you comparing apples to apples? Supporting Function First supports one of our own, an enthusiast that has brought a bunch of great products to market that a lot of big guys wouldn�t waste their time on. In case that matters to you - it does to me. Stop supporting the enthusiast that innovates and we all suffer.

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Potato potatoe. Same thing, many different names.

Anti-sway bar then.

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Precisely!

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Will do!

So this got me thinking today, can I find some urethane tubes and fit them into the hole of the trans mount? I can stick smaller tube into larger tube until I get the stiffness I want?

There are many different ways to stiffen the trans mount. People have used "Window-weld", Silicone, etc... The problem being that you really don't know what you're going to get until you try it. Seeing as the mount itself costs around $80 ($100 after shipping) it could get expensive pretty quickly of you're unhappy with your experiment. Your idea of using tubing (or even solid rubber strips) and stuffing the cavities with them might be worth a shot. Good Luck

btw after looking up some more, I found that Powerflex redesigned theirs back in 2017 as this tread indicated: http://www.911uk.com/viewtopic.php?t...er=asc&start=0 TL;DR version: Basically they found the sidewall too thick and they thinned it out.

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Someone else posted that link as well - looks like powerflex stand behind their product and R&D. I'm going to source a powerflex set locally.

I installed the powerflex with a new transmission mount yesterday and took it out for a drive. No added vibration but the exhaust note seemingly slightly different. The car drives much much better, a lot of weight sway and clunking are gone! My transmission mount has collapsed so not sure how much is contributed to the new mount and how much is contributed to the insert! For shifting the hard to get into first is gone but other than that, all other gears feels the same.

Nice one! This actually dropped off my radar - did you do yellow or black?

I did the yellow one. I posted picture in the other thread of the condition of my old transmission mount. I didn't realize it has gotten this bad and the car really drive massively different now.

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I've been having the same 'whilst I'm there thought' did you replace the mount with the 997 part or 996? I vaguely remember reading the new 997 part could be installed?

I don't know if the new 997 part fits or not. Someone else may be able to help confirm that. The part number I got is 996-375-055-05 on the box. I bought it from sunset when they had the 20% off code shared by Ahsai.

Thanks! Hopefully someone can confirm - not overly confident about the 997 part fittment

I am going to be removing a set of the FF Yellow this week and will be selling them. Too much noise for my daily driver. I do like the performance upgrade but not the noise.

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I did the same on my orange FF. Just can't stand the NVH.

even the soft ones were too noisy?

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Yes, to me anyways.

Thanks, I think I'll stick with some new stock parts.

Thread resurrection! After fitting new headers I have decided to do the trans insert while I'm in the DIY mood. I'm going Powerflex black, I already have semi solid engine mounts, the loudest exhaust I could get from Cargraphic etc. so being over the top seems to be the way my car is going anyway... It's also not a daily driving car so added NHV isn't a concern. Will keep everyone posted, I'm ordering them tomorrow and they should arrive next week.

I have yet to install my yellow ones...Keep us posted.

Went ahead and purchased both the yellow and the black, i'll install the black first and if I don't like them ill install the yellow.

Actually there is quite a difference in the Powerflex and F1 and thats the shore rating: F1: Orange: 60A Yellow - 70A Black - 80A Powerflex: Yellow: 75A Black: 95A Shore example: So the Powerflex is indeed harder in both of their versions - for me I went with Powerflex because of availability and price (the AUD to USD is baaaaaad at the moment and shipping is not cheap). Ideally a "purple" hardness in Powerflex would have been the best of both worlds and exactly the same as the F1 black but Powerflex dont make that insert in purple - only yellow and black. Usually I like to support board members and have purchased items from Numeric racing, Tarret and Eric at BumperPlugs but in this instance the price difference due in part to the exchange rate and shipping was just too great. I'll keep everyone posted on how I go, hopefully I like the black as I know I won't want to swap them out!

I’m interested in your findings. I put F1 black in mine and it felt like someone had backed out all the bell housing bolts.

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That doesn't fill me with confidence as the powerflex black are even harder than the F1 black. Is your car a daily driver? I've got 964RS engine mounts and didn't notice any added NHV. Also a fairly loud Cargraphic exhaust too.

I've currently got the FF Black insert in my tranny mount (which was totally collapsed when I put the insert in). There was a notable increase in NVH. In the meantime, I've gotten a new tranny mount bushing and the Powerflex yellow insert (which is apparently only slightly softer, but hopefully between it and the new bushing will reduce the NHV a little bit). I'll try to get them installed in the next week or two as I've gotten most of my other "priority" stuff (oil change, IPD Plenum/GT3Throttle body) out of the way.

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Hey Dan, yes, mine is a bit of a daily. I�ve been swapping suspension links to all pillow ball and don�t notice my additional NVH, but sure did with the FF black. Your experience may be different as others seem to use them.

Thanks everyone ill give the black a shot and see if they don't work out I've got the yellow to use. Just with the installation, planning rear on jackstands then a bottle jack/small jack under the transmission - undo the carriers, soap the inserts and reinstall?

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That�s pretty much it. You may need to trim an edge with an Exacto to get the right position to put the carrier back up flush. When I put mine in I had to use a rubber mallet on one side to tap the insert fully in to the OE rubber.

Perfect! Thanks

I ran the Power Flex black for about two weeks, around town it was kind of cool hearing the sound of every moving part in the motor, the wining of the gearbox but at highway speed it became unbearable, like the engine room in a cargo ship, switched to PF yellow all is good. Currently running the yellow in a new mount seems to bet the best compromise for any street driving.

Yikes that bad I'll report back on my findings - worst case ill switch to yellow or maybe F1 black which are 80A.

I'd start with the yellow!

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Hurmm thinking about it

Also just purchased the Numeric racing NM202 cables for a while i'm there installation! Ahh the odd justifications I come up for purchasing parts for this car! Gahhh

Okay so finally got aroubd to installing these! I've gone the black and if I don't like them I'll use the yellow I bought. Few notes on the installation: - I tried wedging in the insert after I coated it with silicone based lubricant - didn't work I even tried tapping it in - still nothing. The top was much too tight which seems strange as all the weight should be on the bottom of the mount - strange. So what I did was slightly move the centre steel part down with the through bolt and the mount slipped right in no hammering pushing etc required. BRILLIANT SIGH OF RELIEF - Also recommend using a bottle jack to support the transmission rather than a trolley jack - allows for more control + its smaller and you don't have to move very far to raise/lower it. I adjusted the jack a few times before I found the best position that would allow the bolts to be removed most easily. The mounts metal section does have a bit of play in it so its a bit compensating. Luckily the bolts went in without me having to readjust the jack. - You do need to remove the two studs to get enough access to allow the inserts in (or at least I had to) they have a 7mm head Torque everything back up to spec of 48ft-lb for all 8 bolts (2 x through bolts, 2 x upper carrier bolts, 4 x lower carrier bolts) - all the bolts have a 15mm head.

Okay so update - test drove today but had the centre console out. Oh wow its noisy in the cabin now - although the console being out will contribute to the noise so ill re-eveluate when its back in. Worth it? Not entirely sure yet there is added noise/vibration which i'm okay with as I've gotten used to it fairly quickly. Don't know if I can feel any benefits to this upgrade yet. Verdict: too soon to tell - this upgrade will not be for the gen-pop - at least definitely not the black

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Let me know if you decide to sell. I've been wanting to try a set.

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Dan, Did you install the Numerics already? Also, did you adjust shift cables while console out? By-the-by just the trans mounts may only be in evidence under certain driving parameters like downshifting under braking or accelerating out of corners. Upgrading mounts, bushings, cables, shift kits, exhausts, etc.; and experiencing self-induced NVH seems pretty gen-pop to me.

...and just read your post about the cables.

Gen-Pop?

General population.

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Thanks Hatch! It's 5am and I'm not all there yet. And?

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To be honest I won't be uninstalling it any time soon but on the upside the PowerFlex version are fairly inexpensive Sorry meant NHV in terms of this insert - from what i've read - most people are correct it adds a LOT of NHV - I did 964RS engine mounts and didnt feel anything. This mod you basically hear everything - definitely not for everyone Still undecided - after 2,500rpm its fine - takeoff and 1st gear are not good - reverse is terrible also because I have an LSD the noise is really really pronounced. Although more driving over the last few days - all the slop in the transmission is GONE - shifts into gear perfectly, it's really forgiving in terms of getting in and out of gears - feels really precise. I'd say if you're going to do this actually might be worth going to the extreme of removing the carpeting and laying down some dynamat to absorb the noise - especially under the rear seats/transmission hump. Put it this way - if I ever put my car up for sale - i'd be removing this insert as without a doubt it would scare away potential buyers.

^^ Ha ! That's the yellow or the black ones? I've got the black ones (Function First) in mine, and the first time I started and drove the car after installing them I thought screwed something up... Also, after installing the Numeric shift cables it got noisier still as there's more transmission noise coming through the cables.

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Yep thats the black ones - the PowerFlex black are 10 "shore?" Is that the values name? Anyway 10 harder than the F1 version (95 vs 85). I've got the Numeric cables as well. Take away the noise and the feel is spectacular. I've been thinking about some dynamat but honestly its only low speeds you can hear all the noise then as rpm increases I can just hear engine noise. It's awesome - i'll keep them installed until I get sick of them and can be bothered removing them and maybe move to the yellow. Anyone thinking about which insert to get - best go yellow - black is a very acquired taste

Reviving this thread - to be honest I'm over the black... Going to put in the yellow when I get the chance and see what they are like. The black aren't ideal for a street car... I'm almost used to it but I don't know if I like the feel or noise of them. Anyone running powerflex black? Can't remember.

Does anyone have pictures of the install process, or know of some online? I'd like to replace my worn out stock transmission mount but I like to see pictures of the process first. Thanks...

I finally did my transmission mount on Saturday - after owning the tool and the mount for over a year Go to AGA Tools - there's a video there (sketchy as it may be) The one major criticism I have of the video is that after showing you how to extract the existing mount, they just say "to install the new mount, just reverse the procedure" - while not totally off base, this isn't exactly accurate either. It would be nice if it were a little clearer and explained exactly how to proceed... In addition to the new mount, I also replaced the Function First Black (track) inserts with Power Flex Yellow (street) inserts. Big difference in NVH! It's really a lot quieter. I noticed it right away, but the real test was when my GF got in and said "oh wow! so much nicer!". **If anyone wants to buy a set of FF Black Transmission inserts, you can have 'em for $50 free shipping ! (I paid $130 - They're in near perfect shape).

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I ran black inserts for a few weeks, fine around town but 1 1/2 hours on the highway sealed the deal, switched to yellow until i installed a new factory mount.

Thanks everyone, switching to PF yellow soon as I get the chance bought them along with the black just in case. The black are great in feel terrible in highway noise

My experience was the same. I am interested to see how the yellow ones work out, might be an option for me, as I couldn't tolerate the black either.

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Did you remove them completely I guess? Interested in how the yellow work out as well I think they will be the best compromise

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I tried to tell you!

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You did, you did but I still had to try it! It's not a fun job either

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I think the yellow ones will be fine. I lived with the black ones for almost 3 years - certainly not intolerable, but definitely way more NVH

Going to keep them installed until I find the time to swap them over.

For PDK it is barely tolerable, but for manual even the "orange" insert transmits every gear change and clunk into the cabin. I went through that route with "black", "yellow" and then "orange" and have to finally take it off. Its not the regular highway cruising that makes the NVH, but the noise of every gear change while you shift. And you notice the transmission is right underneath you.

I'm on the fence now as to add the PF yellow or just change the damn mount at the same time. I really don't look forward to doing this with jack stands and a really bad back.

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^^ Yeah, it's kind of a b!tch... I didn't lift my car high enough and was pressed for time, which made it even worse Being very used to what the Black (FF) inserts were like, the Yellow (PowerFlex) are MUCH quieter! My original transmission mount was also compromised, so that may have added to the NVH with the black inserts. The Yellow inserts are being used with a new Mount/Bushing - so that could be part of the equation.

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Yeah, my mount was in good shape visually ,so I just took them out completely. I�d consider the yellow maybe. Bill, a creeper is your friend. Makes it much easier on the back. In fact I personally find it easier on the back than a full lift in some cases (such as these mounts)

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Understood but, there's less room to work when on jack stands. Plus, I have long arms and need as much room as I can get. Lying on concrete is not the issue, it's getting up and down that hurts.

If you have a 997.2, then the AGA tools won't work for changing transmission mount. If thats the case you only have 2 options. Use the inserts and hopefully the NVH noise does not bother you, or get the transmission mount changed which requires the transmission to be off the car and using a machine press to get the mount off the transmission. I elect to wait till the clutch needs replacement and then do the transmission mount at the same tme.

"If you have a 997.2, then the AGA tools won't work for changing transmission mount." I could have sworn I was in the 996 forum...

Totally agree this job is a pain although hopefully won't take as long the second tinlme round!