Review: JHM Stage 1 Clutch/Lightweight Flywheel

[petraman]

Since there aren't a ton of reviews for A4 clutches and flywheels (particularly the JHM, which I kind of took a leap of faith on), I figured a semi-detailed review might be helpful for people looking to replace their busted dual-mass flywheel, a slipping clutch or for a nice upgrade in feel. And yes, you will feel a pretty big difference between this and the OEM setup. Read on to see if it's right for you.

Presentation

This is it, in the box.


I'd add more pics, but there really isn't that much more to see (being honest, I didn't take any more pics... my bad). The flywheel is bare aluminum and the only aesthetic addition is a laser-inscribed "JHMotorsports" around the hub. To me, this is a huge plus. i've seen companies like ECS and EC pull out all the stops in anodizing their flywheels and pressure plates different colors, but really, what's the point? Once it's installed, you'll (hopefully) never see it again, so I'm glad money was saved on a no-nonsense approach.


Performance

Oh yeah, there are some great benefits... Number one, and I know I can't properly quantify this, I swear I gained ~25 hp on the butt dyno. Really big difference, although some of it can be attributed to the addition of a HFC at the same time (really wish I could have tested the two separately, but oh well). Engine braking is now more effective, thanks to the decrease in rotating mass. Rev matching is SO much easier and more satisfying. Just takes a little "tap" of the pedal to get it up to speed, you don't even need to think about it. However, the flywheel is still heavy enough that the revs don't drop instantly, which would have resulted in rough shifts. 9/10 times the RPM is right where you want it. There's now a nice "springy" feeling to the clutch pedal, which takes a bit of getting used to, but I actually ended up enjoying this because you never have to guess at the bite point anymore. It's clear as day, and makes starts from a stop much more consistent. I'm pretty sure it goes without saying that there is absolutely NO slip in the clutch, even when you're launching or power shifting (not that I've done either of those things... haha). Overall, it adds a good bit of fun. Cue the "should have come from the factory like this." Well... I might not go that far (Read the next section.)

NVH

So, here's the issue most people have with lightweight flywheels... They chatter, they make groaning sounds, vibrations... I've heard a few complaints. The trade-off with JHM's is nearly negligible. The only time you'll ever hear anything out of the ordinary is accelerating at a REALLY low RPM. As in, something you shouldn't be doing anyways. On the highway, cruising at 70 in 6th, you won't hear a difference, even on hills with the cruise control on, up until you decide to pass someone... If you give it too much throttle, you'll probably hear some groaning (I might get a video of this if people are interested). Chatter? I definitely can't hear any from inside the car. Even with the windows down... nothing. The only time I've ever heard anything close to chatter was when I had my head under the car with the A/C on. Even then, you'd have to look for it. The clutch takeup is butter-smooth, and won't be an annoyance in bumper-to-bumper traffic. It's very easy to modulate once you get used to it. I'm a very particular person when it comes to NVH, and, to me, these are acceptable trade-offs.

Conclusion

So... Is the JHM Stage 1 clutch/flywheel right for you? If, for whatever reason, you need to replace the OEM setup already, I'd say it's definitely worth it. If your clutch/flywheel is in good shape and you're not planning to add any more power, I'd be hesitant, based on price alone... If money isn't an object, there are quite a few benefits I mentioned that you might find advantageous (more direct clutch pedal responce, solid shifts and launches, satisfying rev-matching, more power), but still... it's a lot. It's a mod that improves quite a few parameters of the car, and overall I'm very happy I went with it over OEM.

9/10, with the only cons being price (although comparable to other clutch/fw packages) and a little bit of added NVH (which was less than expected)

One more thing...

I feel like I have to mention this as a warning... JHM originally sent me the wrong clutch disk. We didn't find out until the transmission was separated from the car. Luckily, the shop caught the difference before the clutch was installed, but if somehow it wasn't, I'd probably be stuck with another few hours of labor to change it out again. They also didn't charge me for the additional time the car was on the lift while waiting for it to ship, which leads me to the real issue with this situation. I understand mistakes happen, especially since the clutches look pretty similar (see below), but it wasn't just an inconvenience to me but my shop as well, as my car was stuck on the lift until they got the new disk. They came to a resolution quickly and were able to ship the disk the same day... however... they would only pay for ground shipping, which would have easily taken another week from CA. Another week of a rental car, another week with my car occupying a lift at the shop... I ended up paying $30 for 2-day shipping. If you make a mistake on a shipment worth upwards of $3k, what's an extra $50 to ship the replacement part overnight as a courtesy? I really hope JHM reconsiders this policy in the future. Full disclosure, they did give me free shipping on the initial order, which I'm still very appreciative of, and they still make a great product, so I'll probably continue to do business with them in the future... although I'll definitely give future shipments a thorough inspection before installation. Aside from that, Jake was awesome to work with, and I appreciate him answering all my questions.

Clutch comparison:


Used B8 clutch on the left, new B7 clutch on the right.


Props to German Auto Pros for the install... If you're anywhere near the Cleveland area, I highly recommend them. Cary's a stand-up dude, and very knowledgeable of all things VAG. Labor was about half the cost of the dealer, too.

[mcgough52]

Thank you for writing this review! Reviews on lightweight flywheels and aftermarket clutches are few and far between for our platform! I've been debating between the ECS, Eurocode, and JHM kits for months, and think I'm close to making up my mind. I do have one question ... did JHM provide you with a torque rating on the stage 1 kit?

[petraman]

I'm glad you found it useful! I agree, it was difficult to research flywheels just because there wasn't much feedback on any of them.

I don't think JHM ever stated a specific torque figure, but it's a B7 RS4 pressure plate with an OEM B8 clutch disk. I think it's safe to assume it can handle at the very least 320 lb-ft of torque (which i know isn't much). However, I actually asked the same question to Jake, and this was his answer:

The same stage 1 set is what we use on our in house big turbo B7 A4 that sees a lot of track time. You should have no issues with stage 1!

So... that's a good sign. I can tell just from driving it, though, that it'll handle quite a bit more torque than the stock clutch... It just grabs SO hard.

[mcgough52]

I'm glad you found it useful! I agree, it was difficult to research flywheels just because there wasn't much feedback on any of them.

I don't think JHM ever stated a specific torque figure, but it's a B7 RS4 pressure plate with an OEM B8 clutch disk. I think it's safe to assume it can handle at the very least 320 lb-ft of torque (which i know isn't much). However, I actually asked the same question to Jake, and this was his answer:



So... that's a good sign. I can tell just from driving it, though, that it'll handle quite a bit more torque than the stock clutch... It just grabs SO hard.

Good to know! Sounds like stage 1 will be plenty for a standard K04 build.

[petraman]

Yep, I think anything short of an EFR/slowone11 build should hold up just fine with this clutch!

[petraman]

One thing to add...

If you're going to install a higher clamping force clutch, make sure to get the transmission mount insert (I specifically got the Eurocode insert because it was cheap, but they're basically all the same)! Just installed mine and it made "aggressive" clutch operation MUCH more smooth. It also took me about 15 minutes to install... most of which was just getting my ramps and tools set up.

Every dollar I throw at this car so far (except for my tinted tail lights, which I promptly removed) has made it SO much more fun to drive, with very little effect on the traits that sold me on the car in the first place (quiet, smooth engine... firm yet comfortable ride). I think the only way to properly own one of these cars is by modding the crap out of it.

[mcgough52]

I would like to add my experience to this thread. After reading this thread, and speaking with the OP, I decided to pull the trigger on the JHM Stage 1 Clutch and Lightweight Flywheel. I also purchased JHM's solid shifter linkage, as well as a stainless steel clutch line, also made by JHM (but not advertised on their website). The new parts were installed last week, and I have put approximately 400 miles on them since the install - some highway miles and some city. I wanted to wait until the parts were broken in before posting any reviews.

I have to admit, I was nervous at first. When I picked the car up, it made a lot of noise. There was a LOT of chatter, especially under 3k RPMs. However, after a few hundred miles, the chatter has reduced A LOT. It is still there, but only in lower gears, much quieter then before, and only ≤2,000 RPM, ±200-300 RPM. I believe that a Fluidampr would likely all but eliminate the remaining chatter. It has reduced to the point where it no longer bothers me, and I hardly notice it - except for cruising through my neighborhood at low speeds.

As for the clutch, I can't say that I have launched it yet, or driven it very hard. I was advised to put at least 250 city miles on the new clutch before launching, but I am going to wait a little longer, just to be safe. I am VERY paranoid when it comes to a clutch, especially after spending $3000+. However, I can definitely say that this clutch is stronger than stock. The pressure plate is from a B7 RS4, and the clutch disk is the same unit used in JHM's B8 S4/S5 performance clutch kit. So far, absolutely NO slip. However, amazingly, the pedal feel is JUST like stock. If I didn't know there was a new clutch, I would swear it was stock. Also, because the clutch line was upgraded to a stainless steel braided unit, the pedal feel remains consistent. The engagement is slightly different, but it doesn't take long to get used to.

In addition to the clutch/flywheel and clutch line, the other upgrade I went with was the JHM Solid Linkage and Cross Rod Upgrade. Made out of almost entirely metal, rather then plastic and rubber, the new linkage brings all of the transmission upgrades together nicely. I also installed an ECS transmission mount insert several weeks ago, which also helped the shifting experience. Now, with the addition of the JHM linkage, I feel as though the car delivers a much more engaging and analog shifting experience. The play in the shifter is reduced dramatically, which makes each shift feel more deliberate. I no longer stress about missing a gear. The shifter goes exactly where I want it to. When changing gears, you hear a very satisfying and well defined metallic "thunk" - like shifters on vehicles many decades older than my A4. Additionally, since I have NOT yet installed a short shifter, the JHM linkage has not introduced ANY additional NVH. Honestly, I don't really feel the need to install a short throw shifter. At least not yet. I am TREMENDOUSLY satisfied with the experience my car provides. I have driven many manual transmission vehicles, and none feel as good as my B8.5 A4.

Overall, much like the OP, I am very satisfied with the JHM Stage 1 Clutch and Flywheel, Solid Shift Linkage and Cross Rod Upgrade, and Stainless Steel Clutch Line. The only downfall is price. Plan on spending $2000+ for the parts, plus another $750-900 for the labor. The clutch line added about 2 hours of labor to the overall cost, which was expected - they said it was relatively easy to install, just time consuming. Adding the solid linkage didn't add any additional labor, as the transmission is already out. I also had the shop replace my rear main seal - just for good measure - $45 in parts and no additional labor. Shout-out to Rennen Imports in Tampa for the excellent install, customer service, and working with me and my schedule while I was on vacation. I will post again once I am satisfied that the clutch is fully broken in.

[mcgough52]

Oh yeah, there are some great benefits... Number one, and I know I can't properly quantify this, I swear I gained ~25 hp on the butt dyno. Really big difference, although some of it can be attributed to the addition of a HFC at the same time (really wish I could have tested the two separately, but oh well).

As to this statement... you are SPOT on. I STRONGLY believe that this flywheel's reduced weight - between 7 and 10 lbs - is helping to put more power down to the wheels. I had no other performance upgrades done when the clutch and flywheel were installed - at least not any power adding ones, and I too feel a decent increase in power. It feels similar to the power increase going from Stage 1 to Stage 2. Nothing incredible, but definitely noticeable. This change in power would be hard to measure on a Dyno, since dyno runs are made using a higher gear. The difference in power with a lightweight flywheel comes mostly in 1st and 2nd gear. By the time you get to 4th gear and above, the amount of power GAINED is much less noticeable.

[petraman]

Glad you like it! Yeah, my review remains the same... This is a great combo with very few drawbacks. Of course, you're going to have some kind of increase in NVH, but it's more than tolerable IMO. I'm kind of jealous of your shift linkage, though... I have a short shift kit that I haven't gotten around to installing (I just haven't been able to set aside a day to do it... knowing myself, I'll need the whole day, haha) and hopefully that fixes the "rubbery" feeling. You can tell it's a nicely shifting transmission by the shift action... and that there's way too much rubber/plastic in the way of a truly positive shift.

[mcgough52]

Glad you like it! Yeah, my review remains the same... This is a great combo with very few drawbacks. Of course, you're going to have some kind of increase in NVH, but it's more than tolerable IMO. I'm kind of jealous of your shift linkage, though... I have a short shift kit that I haven't gotten around to installing (I just haven't been able to set aside a day to do it... knowing myself, I'll need the whole day, haha) and hopefully that fixes the "rubbery" feeling. You can tell it's a nicely shifting transmission by the shift action... and that there's way too much rubber/plastic in the way of a truly positive shift.

Definitely do the shift linkage! It completely transforms the shifting experience, more than almost anything else will. I'm not sure how difficult the install would be, but if its reasonable, it is worth it! By the way, when you first picked up your car after the install, did you experience excessive chatter that eventually faded away? It was very strange the way it occurred. I can't complain, because everything settled down nicely, but it was still strange.

[petraman]

My car was (and still is) absolutely silent at idle... There's still a bit of drivetrain noise at lower rpms at load. I can't remember who said it, but a member here told me it was just the car's way of telling me to shift, and it really is!

Sent from my LG-H918 using Audizine mobile app