OEM Clutch heading south.
 

Background: 07 350Z Enthusiast pretty much stock except transplanted OEM Brembo brakes, custom roll bar and race seat/harnesses. About 90k miles on it. Still have tags on it but it is 100% track car. Run in HPDE4/Instructor about 4-6 times a year.

Had problems with overheating clutch fluid years ago but heat wrap on clutch lines next to cat and Motul 600 solved that problem.

For about the last year if I'm aggressive with the clutch from 4th to 5th it will slip and run rpm's to limiter. Now it happens sometimes 3rd to 4th. Had to nurse it at VIR this weekend. Very gentle (slow) clutch release and throttle to keep it from slipping and several times even when I didn't notice it slipping it overheated and I lost the clutch peddle for a second or two.

So, I need a new clutch. And flywheel too.

I'd like some opinions on good track day clutch/flywheel combos. Wanting to keep it as cheap as possible and don't really need an all out racing clutch as the engine will remain stock as long as it is running fine. No plans at all to add significant HP. It'll never be a race car or even TT probably.

I've looked at Z1. They have a 14 pound flywheel and a 21 pound flywheel. My question is this, will a super light flywheel make downshifting, heel/toe etc harder to do? I'm fairly proficient with the OEM setup but no genius at it.

Also, while the transmission is out would it be worth replacing the concentric slave cylinder with something better than OEM? Anything else I need to think about while its out?

Thanks for any help.

My suggestion is to go with a Nissan Key Value clutch kit. It has all the parts needed for a complete clutch job. As you say, no sense in spending a lot on a lighter clutch/flywheel combo if you're staying in stock trim. I'd spend my money on a replacement external slave cylinder to replace the CSC.

Thanks. I have had no performance issues with the stock clutch so you're right about not needing to get into performance stuff. Where do you find the Nissan Key Value clutch kit? I've looked at the Z1 external slave cylinder kit. Its $440 but they highly recommend replacing the master cylinder is another $200. That's $660 verse $140 for the CSC....but I've had to replace the CSC once, but covered under a FSB, so it was free...but won't be next time one fails.

Quite the opposite, a lightweight flywheel makes heel toe faster, more accurate and consistent. As long as it doesnt affect your classification this is the primary reason to do it. And depending on your proficiency the improved downshift synchronization should result in longer synchro life.

I run the 14lb JWT since 2005 without issue. Replaced the trans last year due to 5th gear grind, the friction surface looked great but I replaced it for good measure. Was much easier (and cheaper - $63) than resurfacing or purchasing a new flywheel. Thats why I give the JWT 14lber the nod.

If your goal is to make the car bulletproof, you should definitely eliminate the CSC.

Personally, I think a lighter flywheel makes rev matching and heel/toe easier. I'm sure some will disagree, but the rpms jump higher and quicker with the light flywheel when you "blip" the accelerator. There's a little bit of a learning curve, of course. I went with the JWT clutch/14 lb flywheel - a little over $700.

I know that CZP and Z1 sell their own combos for a little cheaper if you're trying to keep cost down.

I love my light fly, makes heel toe easier for sure. JWT has held up to tons of track abuse you are looking for.

Coming from a former owner of the Tilton twin-disc ultra-lightweight clutch and flywheel, I can only say there's some tradeoffs in their use.Yes, they allow the VQ to easily rev, and rev-matching is easy. But the VQ really likes a bit of flywheel/clutch inertia to add to its topend power. Without a specific tune, you'll lose some topend and this balances out the rapid acceleration and easier heel/toe use. After racing under SCCA and NASA rules with the OEM clutch, I find it's an easy adjustment to use the stock clutch.

As to the Nissan Key Value clutch kit, they're available through Nissan dealers and Genuine Nissan parts vendors online.

Can't beat this and before anyone says anything about ebay clutches, this guy has almost 150k 100% positive feedback

https://www.ebay.com/itm/KUPP-HD-CLU...2:pf:0&vxp=mtr

Thanks guys. Z1 also makes a mid-weight flywheel which is 21 pounds. I might split the difference between the 14 pounds and stock which I think is around 30. Don't want to lose any top end since that is the only thing that keeps me in front of the Miatas. :rolleyes:

Got some emails out to some of the (Charlotte, NC area) Nissan performance shops for estimates. Will just take it to a regular import shop (closer to home) if I don't hear something soon. Clutch, flywheel, Wilwood master cylinder and CSC delete should be well within the scope of a basic shop I would think....but not sure.

Currently leaning toward Z1 mid-weight flywheel, basic Z1 clutch, Z1 CSC delete and Wilwood master cylinder. Will go ahead and get the heat wrapped stainless steel clutch line too.