Quantcast

Godd@mn cars. VW, Not VW anger content.

blackohio

blackohio

Generous jaywalker
Mar 12, 2009
2,773
122
Hellafornia. Formerly stumptown.
So. I bought a new slightly built motor. New motor has a lightened one piece flywheel/Ring gear on it. When putting the PP/Clutch in, the OEM stretch bolts are too big for the flywheel. The oem flywheel bolt has a diameter of 7mm with a 1.00 pitch to it. These are partially threaded, stretch bolts.

I went and got 6 fully threaded stainless 10.9 6mmx1.00 bolts in just 1mm shorter than oem. They thread in where the OEM won't. I think the flywheel might be a F1 Racing Clutch System unit. But while threaded in (by themselves theres a slight bit of play - don't know if that is an issue or not)

VIDEO OF SAID PLAY.
http://s677.photobucket.com/albums/vv139/blackoh1o/?action=view&current=IMG_2530.mp4

Im going to try to find some 6mmx26 1.0 10.9 stretch bolts tomorrow rather than these stainless ones as I worry about them backing out.

Heres the flywheel. Anyone know what this is? It definitely does not use the OEM stretch bolt size. Who would make a flywheel using a noncom bolt size.


Any issues you guys can think of not using stretch bolts? Using stainless steel bolts? And lastly wear on the flywheel.
 
Westy

Westy

the teste
Nov 22, 2002
55,827
21,844
Sleazattle
I hope that the 6 and 7 mm dimensions you speak of are not the bolt diameter. Just use plenty of Loctite black and you will be fine.
 
jdcamb

jdcamb

Tool Time!
Feb 17, 2002
20,027
8,745
Nowhere Man!
There is a point where you need to call a friend with experience. Pull out your wallet and let your friend help you. Possibly box up the parts and take them and the car to a shop and allow them to take over to protect your invesment and sanity. As a personal example. I work on my car. I replaced a part to save some money. I didn't know that the reason the part had failed was because another part had failed. So again the part failed and had to be replaced. I sought advice on the internet to get where I was at. The same idiots that helped me initially called me out for not knowing to replace both parts??
 
blackohio

blackohio

Generous jaywalker
Mar 12, 2009
2,773
122
Hellafornia. Formerly stumptown.
This isn't my first motor swap, just first time ever seeing a non-oem bolt size on a flywheel.

Thinking I'm gonna pull the flywheel, take it to a machine shop and have it drilled tapped for 7mm oem stretch bolts and have it slightly resurfaced. problem solved.

Westy, 6/7 are the diameters. There are 6 - 7(oem) bolts holding the pressure plate to the flywheel. Flywheel to crank is via 12 - 10mm stretch bolts. Those bolts are fine strength wise, I've seen some high HP VR6's run oem bolts there without issue.
 
buildyourown

buildyourown

Turbo Monkey
Feb 9, 2004
4,832
0
South Seattle
I'm at just about the exact same stage of my motor swap into a VW.
Not sure why a PP needs stretch bolts. I would not use SS but rather 12.9
What motor is that. 1.8t?

I like your logic on the machining. Clears up any and all concerns.
 
blackohio

blackohio

Generous jaywalker
Mar 12, 2009
2,773
122
Hellafornia. Formerly stumptown.
Found out today, BBS Motorsports hardware is 10.9 grade, 6mmx25mm w/ 15mm partially threaded bolt 1.00 thread pitch.

Exactly the same size as the OEM bolts sans 1mm diameter. Boom! done. Ordered the hardware up from my pals at rotiform wheels.

JBP. Seeing as how the factory designated a 7mm bolt and this aftermarket lightweight flywheel used a 6mm bolt, I think it's safe to say VW's engineers know a bit more than this company (who seems to mostly be ebay sales type) Every single lightweight flywheel from a reputable company uses the OEM 7mm bolts. This is literally the only company i've ever seen not use them.

byo - I bought the ss bolts to test fit, then went about trying to find correct steel or alloy bolts. I just need to adjust torque specs of the new non-stretch bolts.
 
spam16v

spam16v

Monkey
Oct 27, 2004
284
0
Buffalo, NY
this some Eurospec sport flywheel or something? Valeo makes some Solid NON bullsh*t Dual Mass flywheels that aren't complete crap. Or get raped by 034 on the same part reboxed.
 
drkenan

drkenan

anti-dentite
Oct 1, 2006
3,441
1
west asheville
buildyourown said:
I'm at just about the exact same stage of my motor swap into a VW.
Not sure why a PP needs stretch bolts.
Click to expand...
The flywheel definitely needs stretch bolts because of the massive torque you have to put on those things. It's normally like 200 ft/lbs + an additional 180 degrees.

I did an Audi clutch by myself and trying to torque those 12 or so bolts was the biggest PITA ever. I had to wedge a socket wrench on the front of the crank shaft to not get it to move. Gives me chills thinking back to those days...glad I got rid of it and bought a VW instead!
 
buildyourown

buildyourown

Turbo Monkey
Feb 9, 2004
4,832
0
South Seattle
drkenan said:
The flywheel definitely needs stretch bolts because of the massive torque you have to put on those things. It's normally like 200 ft/lbs + an additional 180 degrees.

I did an Audi clutch by myself and trying to torque those 12 or so bolts was the biggest PITA ever. I had to wedge a socket wrench on the front of the crank shaft to not get it to move. Gives me chills thinking back to those days...glad I got rid of it and bought a VW instead!
Click to expand...
Flywheel bolts yes, PP bolts not so much.
 
You must log in or register to reply here.
Top Bottom