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Discussion Starter #1
I just had a traffic light launch with a F355 Spyder just now :p I can barely keep above 2 car lengths with the F355 chasing me... And went out of road at the end of 4th gear :( The F355 driver gave me a thumbs up at the end of the little race :)

The stock clutch really can't handle all the power, the flywheel is way too heavy and I had to let the idle drops before punching the gas after each shifts... I shift decently fast and having to wait for the idle is really taken all the fun out of it, I guess before I get the clutch replaced, I can never enjoy the full potential of the E39 :(

Any comments on UCC stage 1 for street use? I know the lighten flywheel will be noisy, but how noisy is noisy? Does anyone have any sound clip?
 

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With the stock M5 clutch you definitely have to wait until your foot is nearly off the clutch before punching it again. That should give it time enough time for the revs to match. With practice and DSC off, there is enough to squeel the tires going into 2nd and chirp going into third.

PS: Good race against the F355. If I recall, the M5 is a just a bit quicker based on published numbers so you did well.
 

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Larry's M5 said:
Any comments on UCC stage 1 for street use? I know the lighten flywheel will be noisy, but how noisy is noisy? Does anyone have any sound clip?
Hey Larry,

They Used to be Noisey, But POWERCHIP have fixed the problem by raising the idle. :15:

I've just had mine done. In five minutes its an instant transformation.

The noise is only at idle, when you are in neutral with the clutch out. All three things together otherwise no noise.

So by raising the idle, all 3 can never exist. Therefore its quiet.

Each setup is individual. Some are louder than others, But everyone who had heard my car before, says that it is gone now.

Under extreme circumstances, if you really concentrate and listen very closely and know what to listen for, with your head under the car, you can Just barely make it out. :1:

So considering thats not normal behaviour, its 100% totally acceptable now.

check out this thread Rollover rattle cured

:cheers:
 

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Discussion Starter #5
Think I'll wait for my clutch dies before I go with UCC stage 1. And depends on how I can handle the noise, I might or might not get the powerchip... Not sure if they higher idle is what I want :p Thanks for the info though!!

And I was coming out from Lion Rock Tunnel and turning into Cornwall Street when I went into him. He was at the 2nd traffic light and the light turned green as I appoached. So I popped into 2nd and zoom pass him at the light, he was in the left lane while I was at the right, he took off from still so he was way behind me when I got to the 3rd light and stopped. As he stops, he pulled to my lane just right behind me and I guess he was checking out the M5 badge and the quad pipes to make sure it was worth his time LOL

I looked at him through the rear view mirror and knew a friendly launch was in order, so keeping to Greg's advise, I was keeping it at around 1.4-1.5k rpm and launched off with a pretty good start IMO, little tire spins and it was off like a rocket. I started to pull a little ahead in 2nd but the idle wait is really killing my time I guess especially the road was going uphill slightly and at about 140km/h I was about 2 car lengths ahead :D We chased all the way to top of the hill and stopped at another light when we looked at each other with a smile :) If it wasn't 4am in the morning, I'd of follow him to have a bit more fun but oh well...

Most of the F355 over here are F1 but this guy looks like a stick person and I guess if he was in a F1, he'd of caught me mainly because of the stupid shifting rev match wait :( But all in all, I really enjoyed this friendly launch, usually it gets hostile at the end here LOL
 

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Can some of the transmission experts chime in here? Should one wait for the revs to match on an upshift or just let the synchros do their job when the clutch takes hold?
 

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I'm not a tranny expert but I think what your waiting for is the clutch to fully engage. The synchros only come into play when you physically pull or push the shifter into gear. I did a little drag racing in the past and with a good clutch and a fast shift I'd never take my foot off the gas (speed shift) and the clutch would never slip. Boy was that a blast. :1:

Hope this helps
Joe
 

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hehe.. if you want to hear how a lightweight aluminium flywheel rattles, you can come hear mine.... it's pretty bad... lol... even with a raised idle, it's still there... I've gotten pretty use to it by now, but sometimes I still feel stupid at a stoplight, having my car sound like the transmission is about to fall out...

But having said that... the difference of having a flywheel weighing half that of the stock dual mass unit is like night and day... now I just need to wait for a new spec clutch to make full use of the flywheel... I feel like the stock clutch is being tortured everytime I try to do a hill start on these HK roads... =P
 

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Richard in NC said:
Can some of the transmission experts chime in here? Should one wait for the revs to match on an upshift or just let the synchros do their job when the clutch takes hold?
Do you mean let the rpms drop to where they would be in the next highest gear, and then selecting the gear? If that is what you mean, then no, simply clutch in, select the next highest gear, pull the clutch out and reapply the gas. By time the clutch has come out the synchros have already done their job, as the tranny is in gear. Just make sure you have a gear selected before you dump the clutch.
If you wait for the rpms to fall down before selecting the next gear, then using the clutch is unnessesary.
:cheers:
 

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I guess I am really lucky to have both of these beasts in my stable, so here is my 2 cents worth!

........................M5......... F355
BHP ..................400......... 375
Torque lb/ft........369......... 268
Weight kg..........1875....... 1450
0-60mph secs......5.0.......... 4.6

So, the M5 is heavier but has more power - thus, the cars are very evenly matched in straightline performance. The 355 is easier to launch than an M5 but the towering torque of the M5 gives massive mid range punch which is simply lacking in the 355 until you climb higher up the rev band. On tight and twisty roads the lighter, lower and more nimble 355 will walk away and the standard brakes will last longer before fading.
But everywhere else it would be a good contest and purely down to relative driver skills and on that count my money would more often be with the M5 driver. There are a lot more poofter polishers than skilled drivers in the 355 camp and on the limit the M5 will look after you when the 355 is biting the bum of the 'average' Joe.
Either way, they sure as hell are two very special Tipo's
 
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