TECH: Roundel got me in a tizzy--VAC's lightweight flywheel!!

Teutonaddict · 9th July 2003, 18:16

Sorry to start another flywheel discussion, but I just read the 07/03 Roundel article on VAC Motorsports, a BMW tuner/service center/bodyshop/race prep outfit in Philadelphia. I also read about Simeon Mackrides' supercharged E38 OneLap beast, and how VAC installed a BMW six-speed manual tranny and their custom lightweight single-mass flywheel in his journey to create the UberSleeper!

Here's a link (from their former website--some embedded links are dead) that gives an overview of Simeon's E38 with the E39 M5 tranny internals:
http://www.vacmotorsports.com/main/com.html

And here are VAC's offerings in the drivetrain department, including the E39 LTW flywheel:
http://www.vacmotorsports.com/cgi-bi...cat=Drivetrain

And HERE is Simeon's webpage chapter on his transmission/clutch endeavors, including VAC's CNC'ed flywheel from billet T-6061! (LOTS of cool pix!)
http://www.cardomain.com/member_page...=140822&page=5

All this got me thinking about yet another alternative for a lightweight flywheel option for our M5s. I'm not sure if their E39 kit would work in the M5, since it's designed for the 540i, but uses M5 internals (I'm looking into this and will post back).

I should note that their E39 540i kit is $1500, and according to the website, the "kit is sold complete with Flexplate, Flywheel, M5 Clutch kit, and hardware." That's sounding pretty d*mn reasonable to me!

Here are my questions:
1) Anybody on the board with experience with VAC?
I thought HaroldC was going to purchase their LTW flywheel (before he got his E46 M3).
2) Didn't someone else buy HaroldC's former M5? Care to comment on gear actuation/driveline noise?

As you can tell, this is driving me absolutely nuts! It feels like a viable alternative may actually exist out there for increasing both durability and positive gearchange feel through some reasonable upgrades.

Shoot, if this setup can handle Simeon's 4400 lb E38 with 550 BHP, our measly Beasts should pose no problem!

-Dave

young-nyc · 9th July 2003, 20:03

Quote:

Originally posted by Teutonaddict
12) Didn't someone else buy HaroldC's former M5? Care to comment on gear actuation/driveline noise?

-Dave

he never owned a M5 from my understanding...
he had a 540i 6 speed

01M5 · 9th July 2003, 23:16

HA! I knew you wouldn't be able to stop modding Dave

HaroldC · 10th July 2003, 04:02

Dave,

Young is right, I had a 540i/6. I was going to order the flywheel, but decided to save the money and get the M3 instead.

I have seen Simeon's Beast and it is something to see! It also hauls ***** and pulls away from almost everything! I know a guy that also has the flywheel and loves it. It is a great mod, but has one major downside ..... the rattle at idle. If you haven't heard a ltw flywheel rattle, it sounds like a bucket of bolts is being shaken around. It is perfectly normal, and will always have that sound, unless you hold the clutch in at idle.

The disadvantage for E39 owners is that VAC is the only place out there that has a flywheel for the M5/540i. And since it's machined by VAC, they can charge and arm and a leg for it. A similarly made flywheel for my E46 M3 only costs $500 or so!

If you are looking for quicker acceleration without modifying the engine, this is a great way of doing it, especially if you are having the clutch replaced. But the cost and noise may be a deterrent for many. I chose not to get one for my E46 M3 for the noise issue alone.

If you do choose to get the flywheel, I have seen VAC's work, and it is excellent! Tony knows his stuff and is very knowledgeable about BMWs. Good Luck

Teutonaddict · 10th July 2003, 04:21

Quote:

Originally posted by HaroldC
The disadvantage for E39 owners is that VAC is the only place out there that has a flywheel for the M5/540i. And since it's machined by VAC, they can charge and arm and a leg for it. A similarly made flywheel for my E46 M3 only costs $500 or so!

Thanks, Harold (and Young!), for the clarification.

I realize that driveline noise is the tradeoff for the acceleration/positive engagement, but I think I might be ready to take the plunge... I read another recent thread about a boardmember with Dinan's Stage-II (single-mass) flywheel, and he even posted some MP3 files of the chatter.

As for the pricing, while they may be steep, they still beat Dinan! At $1500 for flywheel and clutch kit (if the 540i price applies to the M5), it's not too terribly far from OE Parts Department prices. And when you see the pix (link above) of the piece being CNC milled from a billet of Al, it begins to seem reasonable....

I know UUC has come out with a line of flywheels for the E36/E46, so I imagine some E39 goodies may not be too far behind. It sounds like VAC's attention-to-detail may beat UUC's, however...

Thanks for getting back to me! I'll let you know what I end up doing.

-Dave

phillym5 · 10th July 2003, 07:04

guys,

im very good friends with VAC. when i first saw the 740 they were doing the diff. they actually measured my diff to make his.

im proud of that.
anyway, i talked to them for a while about the flywheel because there was an extra one. they made two for the 740. i dont remember why, but it didnt work. there was something differen. ill call them tomarrow and get the whole scoop. there located in philly and are stand up guys. if you want to call yourself, the name of the shop is vernans auto on 25th st. philadelphia. just call iformation. ill post what he tells me tomarrow anyway.

josh.

tfung · 22nd September 2003, 08:02

any update for this?

phillym5 · 22nd September 2003, 16:46

i will call them today and see what they say.

josh.