I wanted to give an update and a shout out to Josh at JNZ Tuning. I know I can go put a shoutout in the Good Guys section but he gave some good specific recommendations that I wanted captured where people are more likely to search. So I'm going to paste his email in here. I'm now running an FP68HTA at around 20psi with all necessary supporting engine mods, and of course my stock clutch (as far as I know) is starting to slip. It was time to start looking for the best clutch upgrade for my car and I did a ton of searching around the internet. There are so many options out there in regards to flywheel, pressure plate, clutch disc combo that I finally decided to ask an expert. I sent a message to one vendor on Facebook about a week ago asking the question and I still haven't received a response. I emailed JNZ off their contact page on the website and had an answer from Josh the next day. I told him my mods and asked his recommendation on a clutch and here was his answer:
Quote:
Kurt,
Clutches are something I dislike getting into advising people on. They're right up there with "which turbo".
Everyone has preferences and while 10 customers out of 20 might love one clutch, 8 will rave about how much they hate it, and 2 will claim that they had a complete failure with it and how it of course wasn't their fault (and, sometimes it wasn't).
Please take the following as personal opinion/experience:
The ACTs are expensive, we as the dealers don't make much profit margin on them, and you have them relying on pressure as opposed to friction to torque hold (not exactly thrust-bearing friendly). I used to go through street discs like underwear back in day with a 2900 when I was racing quite a bit. They'd wear, start to hang up between shifts, and I'd just swap them out with a quick scuff of the plate while I was in there. People's solution to this these days is to go with the 6-puck sprung, which then shocks the driveline more on hard launches.
The Clutch Masters have been out of my suggestion range for a while (although we will still sell them if people insist). It's nice that they use materials that create more frictional hold as opposed to using excessive clamping force, but I've recently seen enough of them have hub failures on the discs to not recommend them. The material (in my opinion--for what that's worth) they use is painfully thin, and they of course deny warranty for this and blame it on the customer.
South Bend Clutches seem to have become "the new hotness" although I've seen that taper off slightly, and I've yet to A) Use one myself, or B) have enough customer feedback on the ones sold to form an educated opinion on them. They're also a little longer to get in stock as the supply chain is not nearly as established as the big-name companies.
You then have the bigger dollar clutches--Exedy, Tilton, Quartermaster, etc.
The Exedy cheap-line (dual plate) units, I've seen warp plates in cars that aren't abused, have veteran drivers, and have been installed to a "T". The more expensive ones seem to hold well, and last, but then you're dropping some serious cash as an entry fee.
Clutch Masters duals are cheap, but you pay with drive-ability. Quatermasters---don't go through the drive-thru at your local burger joint, as they won't hear your order over the noise when the clutch is released.
Tilton--well, it's Tilton. Unless you have a serious competition car, not many people are willing to take out a second mortgage for a clutch.
If I were to build a 400whp car, I'd probably look at the ACT 2600 with a 6-puck, sprung plate, and be very careful with the clutch engagement on launches (or not launch the thing), or take a longer look into people's experiences with the South Bend units. In fact, that's probably what I'll do with a GVR4 that I picked up recently as I'm not interested in building it beyond a fun, sane, 400-500whp car. At the same time, I'd be doing that for a little more experience with their upper-end clutches, and if I pick one I hate, well--then the blame is on my own shoulders and I get to deal with it as opposed to a customer.
As for flywheels, pretty much all of the non-aluminum units work well. I just wouldn't go super light on a street car, and I like a little more mass for heat dissipation as well. I've seen too many of the Aluminum ones fail (ring gear wearing the flywheel, coming loose, and manufacturers denying any sort of warranty) to even recommend them. I stopped doing that several years ago when a customer brought a stock 2G GST in with a Fidanza that had 180 miles on it. The ring gear came loose and was rattling around. He thought it was install error (installed at another shop) causing the noise, but when I inspected it, it the ring gear was flopping around in there. I called Fidanza and they said "We can charge you to replace the ring gear, but that's a race-only parts and we offer no warranty". I kind of paused for a second, and said to the tech guy "So you have an aluminum flywheel, and a tool-hardened ring gear (they use the stock units)---and you're going to sit there and tell me you think that the *ring gear* is what's worn??"
Long-winded answer, and probably not exactly the answer you were looking for.
Unfortunately, there is no "right answer" it's more of a "weigh your decision and pick your poison" kind of deal. There isn't a clutch out there that is cheap, soft on the driveline, has good drive-ability, and will hold up. You just need to decide what your driving style is, and which aspects are most important to you.
Josh
Unbeknownst to him I had gotten impatient and already ordered everything that I felt was best. I ordered an ACT Streetlite flywheel, ACT 2600 pressure plate, with a Street Disk. I felt validated that what I had already ordered was very close to what Josh likes and can't wait for the parts to come in so that I can get it all installed. I might decide to switch over to a 6 puck sprung clutch in the spring if I start autocrossing. I'm worried that a tranny rebuild will be close behind when I do that. I went ahead and ordered a forged shift fork and stainless clutch line while I'm at it.
