SPEC Stage 1 or 2 vs. Sachs Power Clutch - Any Experience with SPEC

[VFR750]

PP sells Sachs, SPEC, Power Friction, Centerforce, and WEVO.

My Sachs Power Clutch friction surface is getting a little thin, but the pressure plate looks fantastic. You can still see the machining marks. I'd like to replace the clutch itself, but you can't buy the disk only anymore, so Power Friction is the only option to the base Sachs disk.

Recent PP experiences with new clutches highlighted the apparent Sachs cost cutting, by increasing the ID of the friction surface, thus effectively reducing the area, and ultimate longevity. This has been explained away, by Sachs, saying the OD does most of the work, which may be true, however, the clutches still wear over their whole surface, so any reduction in surface area will lower life.

A big deal? Ultimately, yes, now I'm looking elsewhere, as I don't like when suppliers "lower" their costs, at my expense. I want a full size clutch, full life, etc, and I was willing to pay for it, you know what I mean? I should not have to plan on shorter intervals, or hand crafting original parts to fit new parts.

First up, I could go with the Power Friction, a nice option. I don't race, so Centerforce and WEVO products are overkill for me. That leaves SPEC.

The new player is SPEC, and their Stage 1 or 2 kits seems to be comparable to Sachs Power Clutch. They are advertising in Excellence and other magazines. It is impossible to judge them based on their advertising alone. So I thought I'd ask here.

Who has purchased a SPEC Stage 1 or Stage 2 clutch, and what did you think of the kit?

How did the starter ring gear bolt up to the pressure plate?

Compared to the Sachs Power Clutch Aluminum Pressure Plate housing, was the SPEC pressure plate comparably light?

All the parts fit?

Any issues?

Does it work well?

Would you buy it again?

[KTL]

If you buy a SPEC clutch housing you're likely getting a remanufactured Sachs housing. Take a look at the GRM article and click on the blue clutch picture.

1984 Porsche 911 Carrera Updates Page 10: Project Cars: Grassroots Motorsports Magazine

If your clutch housing is in good shape, i'd just get a disc. Get one from clutchnet.com. They make nice stuff. I have used their "puck" style 4 puck and 6 puck spring center discs in my racecar and they are excellent quality.

[twait01]

I don't have experience with the Spec clutch but I did purchase a Spec flywheel for a 3.2 Carrera motor. Spec claims their products are within .001 of spec. The first flywheel they sent wasn't within .1 on the run-out gauge. Spec had me send it back at my expense and sent me a new one which I installed. It appears to be a very nice piece and has worked fine in the car.

[LJ851]

Why not get your friction material replaced on your disc ? These guys here in Atlanta do a great job and can tailor it to your power level/use requirements. Their prices are very reasonable.

high performance clutch Atlanta Georgia, Clutch Specialty Atlanta, GA Home

[Archetype]

I had a supercharged bmw m coupe I installed a 4 puck ceramic SPEC clutch. It began to fail under regular street use within 3-4k miles. When I called hem to help diagnose what was going on ( it began to make all kinds of screeching sounds) they gave me e run around. "Oh you'll have to talk to such and such". Ok..may I speak with him? "Oh, he's in the garage right now...etc, etc.". I replaced it with an m5 set up which was great.

My personal experience with SPEC was not positive all the way around unfortunately.

[guru944]

I sigh with KTL

Just get the disc with a 6 puck sprung hub (copper blend or sintered iron blend) and have it all balanced with your flywheel...

I have got a stage 3 unit on standby for my turbo upgrade. Pretty sure OEM unit is tired and won't be able to handle the torque.

Later...

[tobluforu]

Can't comment on Porsche, but over on the Saab boards a few people have installed spec clutches and they ended being pieces of crap, and they have horrible customer service. I think some have a tendency to over clutch cars thinking they need all this weird friction material, pucks, blah.... If your car isn't a high HP beast, stick with stock.

[KTL]

Yeah for a stock replacement I would get clutchnet's organic stock spring centered disc. No reason to get the puck style for a street car.

[spuggy]

Originally Posted by tobluforu

I think some have a tendency to over clutch cars thinking they need all this weird friction material, pucks, blah.... If your car isn't a high HP beast, stick with stock.

+1 ^^^ this.

A Power clutch is just a cherry-picked (top 10% of spec) stock 915 clutch - and they get marginal somewhere over 300 ft/lbs at the flywheel. So most things short of a turbo are fine.

Sachs 915 Sport clutch and a 6-puck will hold at least 400 ft/lbs at the flywheel (370HP & 350 ft/lbs at the wheels) - probably more. Just like too many reps on a leg press after 5 minutes in stop-start traffic. Daily-drove it for years but I don't recommend it; pucks aren't designed/meant to be slipped - they REALLY hate it.

Mostly track use? Sure, use a puck. They're nice on the track.

Pressure plates either hold or they don't. If not damaged or worn and the fingers still have the clamping force, they don't need to be swapped out with every friction plate - although many, who aren't intending to drop the motor for another 50,000+ miles after a clutch job, replace them with the throw-out bearing and clutch fork - just because it'd suck to do it again in 15,000 miles to replace those parts.

As for Sport or uprated pressure plates - if you're making the sort of power that needs more than a stock clutch, you should probably re-consider the whole 915 thing.

[VFR750]

All good points. I am not making turbo power. The PO installed the Sachs Power Clutch. Other than the lining measuring at 7.3mm, all else looks pretty nice.

Engine drop turned out to be pretty easy, and 15,000 miles is 4 years of track/street driving for me. So full on replacement today, seems wasteful. So does major upgrade...

[TC996]

I have been driving Porsches as my daily driver since 1991 when I purchased a ’88 944S. I have had several daily driver Porsches since that time, after the 944, they were all 911s. I am very familiar with the product, how to drive and maintain it, and I have a long history of service on all of my vehicles from Porsche direct only.

I had one issue with my 2001 996 Cabriolet when I undertook replacement of the clutch; a minor rear main seal leak only. I purchased my car from Porsche as a lease return from a Porsche employee with 50,000 km on it. My car had more than 160,000 km on the original clutch, and it was operating flawlessly when I undertook this upgrade. I elected to upgrade my clutch and flywheel as I wanted the minor leak rectified, and I attempting to be proactive to save myself future labour to disassemble the same portion of the drivetrain to replace the clutch in the future and to increase my car’s performance. My dealer is a Premier Porsche dealer, the Sachs clutch and lightweight flywheel were supplied by AWE Tuning.

The work was completed in the spring of this year, and the car returned to me. Very soon after its return, it became clear that the clutch was not operating properly, and within approximately 2000 km the clutch began to slip and fail. The car was returned to Porsche, who disassembled the clutch to diagnose an repair.

At that time, AWE refused to replace the part without inspection. I waited with my vehicle disassembled for more than 2 months for the parts to be sent away, inspected, tested etc. The Porsche dealer's ability to install the part correctly was brought into question by AWE (I find it extremely unlikely that a dealership of this calibre and reputation could install a clutch incorrectly), my driving style and ability was questioned (clearly, with 160,000 km+ on the original clutch and very little wear it was not my driving style), so by the process of elimination, I do not see how the issue can by anything other than a defective part and/or supply of the incorrect parts. After all of this, it was discovered that AWE had indeed supplied incorrect parts for my vehicle. In the end, the part was replaced and reinstalled.

The problem did appear to be solved, and the clutch did operate properly for several months; then the same symptoms reappeared, and the clutch began to slip again with less than 4000 additional km. That is a total of approximately 6000 km to burn-out two brand new clutches. I don’t that believe that the worst driver could be responsible for that level of wear, so once again it’s not the driver. If it is extremely unlikely that a Premier Porsche dealer installed a clutch incorrectly once, then it is practically impossible that they did so twice, so it’s not the installer.

I returned the car once again. Inspection of the parts shows unusual wear and heat damage. The flywheel is scored and worn as well. I am not a mechanic, but clearly there was something wrong with these parts individually, in combination or with some part that is incorporated in their installation.

I told my service advisor that I did not want to go through the same nightmare again (the dealer was amazing and extremely helpful throughout the entire matter). I instructed him to replace the Sachs clutch with a factory part and to get a refund on the Sachs clutch as it clearly never operated properly. Once again, I was buying a new factory replacement clutch when I didn’t need one in the first place! In addition, the lightweight flywheel is damaged and of no use to me. Luckily, I kept the original flywheel to reinstall, but I had still paid for a flywheel that is either defective of incorrect and was now clearly damaged.

AWE Tuning refused to do anything further to mitigate my damages, simply saying that their parts dont fail.

I was without my vehicle on two separate occasions for extended periods of time, I was forced to purchase a new factory clutch when I didn’t require one, I purchased a flywheel that was unusable and I am out tens of thousands of dollars as a direct cause of my purchase of AWE Tuning supplied Sachs parts.

Its only one person's experience, but after more than 20 years of owning, servicing and modifying Porsches, buying Sachs parts from AWE Tuning was the worst experience I have had.