Lighter flywheel=SRM issues.

Red370 · 09-04-2009, 01:54 AM

I speculated prior to seeing it in person, that having a lighter flywheel would cause issues and sure enough it does! My friend Tony bought the JWT clutch/flywheel combo, installed it this wednesday, well on downshifts, it quickly revs and holds a constant 300rpms over the ideal match, resulting in jerky downshifts when activated. THANK GOD i decided against it. Problem was solved when deactivated, but kiss your SRM effortless downshift goodbye!! Or just dont bother with a lighter flywheel.

shabarivas · 09-04-2009, 02:12 AM

I dont think that is true - are you sure you didnt bust up the clutch sensors while doing the install?

AK370Z · 09-04-2009, 02:27 AM

Quote:

Originally Posted by Red370

I speculated prior to seeing it in person, that having a lighter flywheel would cause issues and sure enough it does! My friend Tony bought the JWT clutch/flywheel combo, installed it this wednesday, well on downshifts, it quickly revs and holds a constant 300rpms over the ideal match, resulting in jerky downshifts when activated. THANK GOD i decided against it. Problem was solved when deactivated, but kiss your SRM effortless downshift goodbye!! Or just dont bother with a lighter flywheel.

How reputable is the shop your friend "TONY" went to? Because some of our member(s) has this setup on their car and SRM works flawlessly. Please DO a little more research before making negative statement(s). thanks. Here's one of the member

TravisJB Journal

Quote:

Originally Posted by travisjb

I'm going to provide a quick update for you all, with more details to come this weekend... just picked up the car and drove home from redline... my impressions are based on 30 min drive home and no time yet to drive aggressively, skid pad test or anything

- jwt clutch... this feels better than stock! not harsh AT ALL... I have no idea how it will hold up over the long term, but I would vote that these cars come out of the factory with a jwt clutch... the overall pedal throw is much shorter now, and the engagement points are exactly where I like them... bonus: you know how on the stuck clutch when you press it in from first to second and you get a springy noise ? well, that's gone now! (EDIT/UPDATE... MOSTLY GONE! NOT COMPLETELY GONE)
- flywheel... as you might imagine, the car revs much faster now, both accel and decel... most noticeable when you really stab the accelerator, or when drop from very high rpms... in fact, while getting used to the car driving home, I missed an upshift while on it hard and in between gears I was blown away by how quickly it shot up to redline... as predicted, SRM works FLAWLESSLY with the new clutch! big bonus for the street, while coasting in gear, you can now let off the accelerator rapidly and the car will smoothly begin to decelerate - none of the jerkiness with the stock setup ! it is actually very fluid and nice ! the only downside i've noticed is that as expected with this light weight flywheel, the car at idle exhibits a few rattling noises... nothing horrible, but you can hear it inside and outside the car... yes, I will capture video/audio
- b&m shifter... this is a great add ! couldn't be happier ! i feel as though i have a better sense for which gear i'm in, because the shifter results in much less compliance and so when you reach down you know exactly where the lever should be for that gear and there it is... with the stock setup, i would sometimes hesitate or 2nd guess which gear i was in because of the slop/compliance... I love the short throws too ! reminds me of a formula ford i recently drove... great add for any application street/track/drag
- carbonetic rear dif... going to take some real driving for me to evaluate this ! sorry, not ready to issue a verdict here yet... i can tell you that redline tested it out and said it was very aggressive and the car will now step out instantaneously but predictably with enough throttle... give me some more time and i'll share more thoughts on it... real test will be going into and out of corners at the limit on next track day... not surprisingly, the rear does exhibit some noises now that it didn't before

Next up will be a customer oil cooler modification and custom rear diff cooler setup... Redline is working both of those for me, and I think you guys will be interested... Also getting the spa oil pressure / water temp gauge in next week...

more to come!

SUPER BIG THANKS TO REDLINE MOTORSPORTS FOR HELPING ME BLAZE THIS TRAIL ! NICE WORK ROBERT AND TEAM !!

Quote:

Location/Event: 13-June @ Firebird International Raceway - East Track... NASA AZ event... ~85F... HPDE4 run group
Mods: Stillen (G3 Intake/Headers/HFCs/Cat-back/UD Pulley/Sway Bars), BC Racing ER Series Coilovers, JWT Flywheel and Clutch
Wheels & Tires: Stock/Street
Sponsors: Redline Motorsports, Forged Performance, Doubledown Motorsports

Had 3 very enjoyable track sessions today! FIR East is a short twisty track, with plenty of run-off room, so it is great to run while tuning and getting used to a car. Of which, you may notice a couple missed shifts etc, so let's just keep that to yourself huh ?!

Fast lap of the day was 1:06.4, which I am very happy with. A 911 GT3RS ran ~0:59, which was the fastest car at the track today. Fastest car in the race group I will eventually run with (NASA PTA) was 1:02. Overall, I think with weight reduction, sticky tires, and some tweaks to improve braking, I should be competitive at this track. NOTE: my camera is currently in a less than ideal location, so you may be a little disappointed with the video. Will be fixed by next track day. If you want to skip to my fastest lap, go to video 2 and find lap #4. AND TURN YOUR SOUND UP!!!!

In reverse order, here is my 3rd and final session:

2nd session:

1st session:

IMPRESSIONS AND NEXT STEPS:

Oil cooling... this continues to be a problem, even with the single core Stillen setup... good news is I never went into limp mode... bad news is I routinely hit 280 and peaked near 290 in a later session... really looking forward to my dual core setup, which is coming soon !!
Suspension... coilovers are performing well... and the car is cornering very flat... I played with the rebound settings a bit but didn't put effort into tuning today... next time out will be corner balanced and perfectly set up and that'll be the time to try and dial in the settings
Power... for this short track, I had ALL THE POWER I NEEDED... when I timed it right, had no trouble keeping up with newer M3s and various race cars... I'm going to address the power/weight issue through further weight savings and will prob stop investing in +HPs... I think with 200 lbs off, I could have saved 1.0-1.5 seconds
Brakes... continue to be an issue... I'm confident that with ideal braking I could have dropped 1.0-2.0 seconds
Tires... remarkably good and controllable for stock tires... these are fun to drive... I'm sure I don't have too much left though ! ... move to sticky tires should buy me 2.0 seconds at this track
Carbonetic diff... very pleased with this! I'm still new to mech diffs and trying to learn how to use it well, but when I played around with my corner exit speed, I found I was able to pretty much floor it coming out of turns and at worst I had very controllable oversteer, at best it sailed out of the corners!
JWT clutch/flywheel... this is a no-brainer... if you have the $, do it... makes driving much more smooth!
Summary... feeling pretty good about the car... I think with just a little more work, I may be able to turn a 1:02 or better at this track

Courtesy: Nissan 370Z Forum - View Profile: travisjb

Red370 · 09-04-2009, 03:27 AM

Quote:

Originally Posted by AK370Z

How reputable is the shop your friend "TONY" went to? Because some of our member(s) has this setup on their car and SRM works flawlessly. Please DO a little more research before making negative statement(s). thanks. Here's one of the member

TravisJB Journal

Courtesy: Nissan 370Z Forum - View Profile: travisjb

No speculation, I seen this first hand. He made a video for the sole purpose of proof, says he'll be joining and posting said video on monday. I suppose something could have gone wrong with the installation, but I wouldnt take any chances with it.

JoeD · 09-04-2009, 03:28 AM

With any car, a proper clutch/flywheel is one of the most rewarding modification you can do. A lighter flywheel will not interfere with SRM operation...that just doesn't make much sense.

Red370 · 09-04-2009, 03:33 AM

well hes going to spend tomorrow troubleshooting the issue to see if the sensor somehow got tweaked, I hope this is the case.

Modshack · 09-04-2009, 10:20 AM

Quote:

Originally Posted by Red370

well hes going to spend tomorrow troubleshooting the issue to see if the sensor somehow got tweaked, I hope this is the case.

I suspect something is screwed up... SRM sets correct RPM for the match. That's engine controlled and really has nothing to do with the flywheel or clutch other than that they will spin at the same RPM the engine controls determine.

Shunya · 09-04-2009, 10:22 AM

Quote:

Originally Posted by Modshack

I suspect something is screwed up... SRM sets correct RPM for the match. That's engine controlled and really has nothing to do with the flywheel or clutch other than that they will spin at the same RPM the engine controls determine.

09-04-2009, 01:54 AM	#1 (permalink)
Red370 A True Z Fanatic Join Date: Jul 2009 Location: Kaiserslautern, Germany Posts: 4,391 Drives: your mom to church Rep Power: 296	Lighter flywheel=SRM issues. I speculated prior to seeing it in person, that having a lighter flywheel would cause issues and sure enough it does! My friend Tony bought the JWT clutch/flywheel combo, installed it this wednesday, well on downshifts, it quickly revs and holds a constant 300rpms over the ideal match, resulting in jerky downshifts when activated. THANK GOD i decided against it. Problem was solved when deactivated, but kiss your SRM effortless downshift goodbye!! Or just dont bother with a lighter flywheel.

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09-04-2009, 02:12 AM	#2 (permalink)
shabarivas A True Z Fanatic Join Date: Apr 2009 Location: Sacramento, CA Posts: 2,188 Drives: 370z MB 6mt Rep Power: 914	I dont think that is true - are you sure you didnt bust up the clutch sensors while doing the install?

09-04-2009, 03:28 AM	#5 (permalink)
JoeD Banned Join Date: Aug 2009 Location: CA Posts: 495 Drives: Z Rep Power: 0	With any car, a proper clutch/flywheel is one of the most rewarding modification you can do. A lighter flywheel will not interfere with SRM operation...that just doesn't make much sense.

09-04-2009, 03:33 AM	#6 (permalink)
Red370 A True Z Fanatic Join Date: Jul 2009 Location: Kaiserslautern, Germany Posts: 4,391 Drives: your mom to church Rep Power: 296	well hes going to spend tomorrow troubleshooting the issue to see if the sensor somehow got tweaked, I hope this is the case.