I'm going to need to replace my clutch soon. Since I am, I was thinking of Getting the GMG Clutch/Lightweight flywheel package. Does anyone have any impressions on this set up?

While the transaxle is out I figured I might as well upgrade to the steel syncros and perhaps change the gearing a little to shorten up 2nd, 3rd, and 4th. And/or change the final drive to something like 4:11. I don't really need to go 170. Blasting from 60 to 120 like a rocket is more to my liking. What would I notice with a light weight flywheel and shorter gearing?

 

faster accelleration is what you will get.
the flywheel is goign to let the engine rev more freely due to less pwoer lost trying 2 rotate a heavier mass (this shows itself as more power on the dyno, you're not really making more power, but you're improving drive train efficiency and allowing the power that the motor makes to reach the ground).

as for the gearing, if you track the car, you should try to match the gearing to the optimal setup for your home course. otherwise, if you shorten the gears you'll get better acceleration, but worst fuel economy (how much depends on how short you go). taller gears = slower acceleration but better top speed.

let me know about the gearing as this is something interesting i'd consider.

 

I have no experience with LWFW but after loosing the "heavy" mass of the flywheel... will it feel like something is holding you back everytime you press the clutch pedal for shifting, since you lost engine momentum from the LWFW?

Does it even make sense what I'm saying?

It's like replacing the factory cats for hi-flow ones... you gain something but you loose something else... like low RPM torque vs end speed HP...

joel

 

Well you wont really LOSE anything....but it will rev up faster as well as rev down faster. Some say its an adjustment to match throttle on downshifts as by the time they blip, and shift the motor has revved down already, but you can either blip a little longer, shift faster, or both....you get chatter except the GMG/Sachs combo will not chatter. Its a stronger clutch to also deal with the lighter FW....not much downside in that combo except the price..lol...

 

I had a LWFW on a past car and loved it. When the clutch expires on the 996, I plan to put one in it also. The only downside I've heard on them is the possibility of chatter, mostly at idle or just when the clutch engages at lower speeds. Therefore, you must never stop and always go fast....

 

I was quoted $2,195.00 for the GMG/Sachs combo. It's up there but not too crazy. I've allocated $5,000 to my drive line budget to ready it in anticipation of the supercharger. In addition to the GMG/Sachs combo, I'd also like to upgrade to the stronger steel synchros and slightly shorter gearing. LSD would be nice too while the transaxle is out of the car. I'm imagining somewhere near 480 HP with 4:11 gears and LSD in a bullet proof drive line. That would be fun.

 

You are adding a SC? Better ask the SC guys about shorter gears or a higher final drive. I would think that 1st and 2nd would be pretty useless in a SC 2wd car with a higher final drive. Just my thoughts.

 

Sounds great!

 

Going with shorter gears AND a 411 final would severly hurt you on the track, IMO. You would have to be in 4th gear at speeds above 80 mph just changing out the final gear. Your 0 - 100 time would drop considerably, too. With a compressor on the car, it would almost be undriveable in any gear lower than 3rd.

 

I was considering either shorter gears or shorter final drive. Not both.

 

Your post states "and/or".



".......upgrade to the steel syncros and perhaps change the gearing a little to shorten up 2nd, 3rd, and 4th. And/or change the final drive to something like 4:11."

 

You're right! I don't know why I said and/or....

2nd - 4th seem too tall for me. I don't have any specific track in mind when I make that statement. I'm just basing it on how I drive. I'm trying to figure out the optimum set up for hard acceleration - not top speed - considering the affects of a supercharger and light weight flywheel.

 

I agree with you....these cars are designed with top speeds in mind even though 99% of the people that drive them dont approach those speeds. I always thought a better geared Carrera would be a much better and FASTER car on the street...

 

I have the EVO LWFW and Stage II clutch and let me tell you HUGE difference.

The only thing is you will HAVE TO GET USED TO THE CHATTER! I am used to it now..but even now sometimes, I am sitting at a red light it sounds like something is broken. It just chatters and sounds crazy. But...the get up and go..and the butt dyno dont lie. The car is super responsive and the car revs so quick. That is probably the most major mod I have done and personally...bang for the buck I think it is the best. The car really feels great.

 

GMG insists their LWFW/clutch package does not chatter. I wonder if that's true. It can't be rocket science, so why would EVO's chatter and GMG's not? Perhaps all of EVO's R&D goes into their superchargers? Let's hope so......

I just reread the article in Excellence about Sportec's 802 HP daily driver. Their drive line mods included steel syncros, single mass flywheel, stronger clutch. and a taller 6th gear to hit their intended target of 250 MPH. The final drive was left stock. I'm assuming "single mass flywheel" means "light weight." This car was designed as a top speed weapon - accounting for tire growth at speed - it does go 250, and it accelerates like mad (0 - 186 in less than 19 seconds!), Granted, it does pump out 802 HP at the crank. However, the fact that with forced induction and single mass flywheel they opted for stock gearing (except for the longer 6th) and final drive is telling.

I opted for super charging my car because - from what I've been able to ascertain from this forum on the topic, super charging delivers the power from down low in the rev range and comes on in a linear fashion. I am not a fan of the kick in the *** turbo charged cars made famous. I think Deputy Dog described it best when he said "it accelerates just like your car does now, only faster." However, I would like to sharpen the focus of my project more toward hard acceleration rather than insane top speed. I would think adding 150 HP to the stock configuration along with lightening the flywheel would require some adjustment to either the gearing or the final drive ratio if "point and squirt" driving is my focus, not top speed. I've addressed braking, suspension, chassis stiffening, and aerodynamics to that end, however I'm still not clear as to how, or if, I should revise the gearing. Leave it alone, shorten 2nd - 4th, or shorten the final drive?