New Clutch/Flywheel Help

[jwest11]

Hey everyone, I want to replace my clutch and flywheel with a LWFW or a SMFW. With cost being a factor here, I am heavily considering the RHD LWFW but since it is only 7 lbs I am concerned about the chatter it will produce (I have heard people say its really bad and some say its not bad at all). Along with the RHD unit I would go with a stock Sachs clutch kit.

My other option is the Valeo SMFW conversion kit from FCP, linked here. I like this kit because it comes with everything I need in one order and is pretty cheap. I know Valeo is an OE/OEM manufacturer so I'm not worried about the quality (though if someone has a negative experience, please let me know). I understand this one isn't lightened but I was thinking I could take the FW to a machine shop so they could shave some lbs off to make a bit of difference in the driving experience but not affect the NVH. Regarding this kit, would it bolt right up and work with my car, I have a 1989 325i with a stock DMFW (mainly concerned about it working with my starter).

The third potential option is to buy an OEM SMFW but those are really hard to find used so i've pretty much written it off.

Would love to hear what anyone has to say on this subject since this is the last "big" decision of my build before I put everything back together.

Thanks!

[roguetoaster]

The downsides of a very light FW really depend on who you are/what you want from a car. Clearly there will be more noise from the transmission, but you'll hear it mostly when stopped, and even then you can make it mostly go away with the clutch. Will there be a performance gain, not anything huge, but the engine will feel much more sporty.

As to which one is best, I'd say the new Valeo kit, as you don't really need your FW to be 7lbs. Also, I believe I have a used M20 SMF on the shelf if you want to go that way.

[jwest11]

The downsides of a very light FW really depend on who you are/what you want from a car. Clearly there will be more noise from the transmission, but you'll hear it mostly when stopped, and even then you can make it mostly go away with the clutch. Will there be a performance gain, not anything huge, but the engine will feel much more sporty.

As to which one is best, I'd say the new Valeo kit, as you don't really need your FW to be 7lbs. Also, I believe I have a used M20 SMF on the shelf if you want to go that way.

The car will be a daily but I don't mind some noise. I will say though, when I had 90A poly engine and trans mount from Gragastic installed, the NVH was pretty bad and I switched them out.

Where are you located? I would probably be interested in purchasing it. With the SMFW, I wouldn't need to change my starter right?

[jbontke]

Ok what about getting 2.5 flat pistons and fit the 731 on top.possible?

I think this should be another thread because I have read on that subject MANY times. Forced firebird has a dyno thread that will answer your questions.