how to install 3b flywheel to adu?

[mcandmar]

Can somebody please confirm what master/slave cylinders you need to use. For example if converting a 3B to a 6speed to you need to change the master cyl for an ABY item?

Thanks,

Mark.

[quattrostyle]

okay that s*cks , thanks for the answer

[Bram]

I have a ABY setup and would like to upgrade to a Sachs Organic sport clutch and lighter flywheel. Can I use a 3B flywheel in combination with a 3B Sachs clutch? Or will I miss some pins on the flywheel?

[Bram]

I was too quick asking. I just found this very good how-to!

http://www.s2forum.com/forum/showthread.php?t=26211

[Rusty]

The Sachs Organis is supposed to be rather good but costs a fair bit. 3B flywheel works on an ABY providing the timing pin is in place on the 3B flywheel, the flywheels are a straight swap, I did it last year. There are other issues with gearbox dowels and gearbox mounts but these are covered in other threads, I think one's a sticky. Get a clutch for the 3B and a 3B flywheel and all will be much better otherwise it's Fidanza time for an aluminium flywheel but that's pricey.

You can get the 3B wheel lightened but ideally you want to get the whole bottom end balanced if you go too light. If you go secondhand then get the friction surface skimmed, I didn't and I regret it as there is a slight judder when warm, more than likely down to contamination or poor surface on the flywheel. I've noticed increased vibration at low revs but the performance gains make it all worthwhile IMO.

HTH.

[Tommy200rs]

Can somebody please confirm what master/slave cylinders you need to use. For example if converting a 3B to a 6speed to you need to change the master cyl for an ABY item?
Thanks,
Mark.

This is an interesting subtopic for the sport clutches and a valid question when using the Sachs 3B race pressure plate 883082-999707 in heavy stop and go traffic
http://www.google.fi/search?hl=fi&q=...&start=10&sa=N

(The Sachs pressure plate ...724 with DM flywheel is light to use. )

The .... 707 is kind of heavy pressure plate to use.

In ABY the master cylinder piston size is about 19mm
The slave cylinder piston size is about 22mm

Aftermarket master cylinders for clutch pedal of smaller cylinder size make the clutch lighter to operate, but the clutch enables free at very bottom or not at all free. The trick is to find right size smaller master cylinder that is lighter to use, can be mounted to 3B pedal enviroments, possible to bleede the air out. Lets find that out and document here.

Sofar there has been found the alternatives for master cylinder:
0,750" 19,05mm (~stock Boge, Sachs)
0.625" 15,87mm (several brand like brembo, alcon, ap racing)

0.65" 16,51mm and
0.669" 17mm
Both would be interesting sizes but not found yet ! *** see below the AP model !

0.700" 17,78mm (Alcon, AP Racing)

The 0,625 (straight flange mount) one is much lighter to use but feels even too light. Final testing is not yet done in my 200 with 3B and 016 5 Gang. Testing delayed due to some other missing parts... I will probaly also test the 0.700" size feel )

I have test used one 0.625" in old 90er body (easy to install!) with ABY engine and 3B type flywheel and it could release the clutch, but heavier to use than in 200. Difference is due to the pedal enviroment differences.

In one with ABY pedal environment also tested and very light , but installing the different kind of master cylinder to ABY was a real pain in the head.

One important thing in the installation is that the original rigid piping and spongy rubber hose part is replaced with steel braided teflon pipe to have minimized expansion of tube AND the flexibility to have the master cylinder as free in cabbin for bleeding procedure (to get the air bubles out from master cylinder).

From the figures you can calculate how much the maximum slave cylinder movement in mm is reduced if master cylinder is smaller.

Does someone have knowledge of available master cylinder sizes from different vendors ? Information would be needed to find such alternatives that are easy to mount into ABY and others.

Alcon, AP Racing, Brembo, Boge, Sachs, ATE, Girling make master cylinders. If you know web links to master cylinder catalogs with piston sizes and part numbers, please post links here.

Alcon:
page 16
http://www.alconusa.com/client_images/files/92_205.pdf

AP:
http://www.apracing.com/info/index.a...Cylinders_2350
Check the Flange Mounted Types
http://www.apracing.com/info/index.a...nge+Types_2385

There seems to be a piston size alternative of 16.8mm
http://www.apracing.com/info/product...Type_2386_2385
*** Full Stroke 25.4mm (1.00")
http://www.apracing.com/info/product...Type_2388_2385
*** Full Stroke 31.75mm (1.25")
http://www.apracing.com/info/product...Type_2387_2385
*** Full Stroke 25.4mm
Those are available with straight flange mount or offset flange mount.

to be continued.....

[Tommy200rs]

Clutch master cylinder finder:
http://frugalmechanic.com/auto-parts...aster-cylinder

One source is mentioning that ATE has had 17mm size version for, but not found yet.

Following brands in finder
* Adler (17)
* ASCO/Aisin (24)
* ATE (5)
* Automotive Products (4)
* Beck Arnley (158)
* Crown (6)
* FAG (11)
* FTE (28)
* Girling (1)
* Nabco (38)
* OE Service (9)
* PBR (112)
* Raybestos (270)
* Sachs (10)
* Scan-Tech Products (1)
* Seiken (3)
* Tokico (22)
* TRW (4)

[Tommy200rs]

Some background and about Hydraulic equation model

The ratio of the piston cylinder sizes (in²) Slave: Master cylinder is what determines the mechanical advantage (softness or the hevy feel of clutch pedal) in the system. An example: If you have a ½" master cylinder piston size [m] and a 1" slave cylinder size [s] , 10lbs of force on the master piston will produce 40lbs of force in the slave. (Calculated from the squares of the piston size radii [r] .

[slave r]² / [master r]² = 0.5" ² /0.25" ² = 4


Volume (in²*in) of fluid moved will determine the throw movement and is the inverse of the above ratio. So in the scenario above, a 2" of piston thrust travel (huge travel!) in the master cylinder will produce .5" of travel in the slave cylinder. If the slave movement or thrust is too little, the clutch releases at the very bottom of pedal movement or not at all. Luckily the pedal end is slightly adjustable. Note that the (old) rubber hoses may slightly expand and then the movement may be smaller and spongy feel. Not much, but a small difference.

Starting point in Audi S2 environment is
Master ~19mm m r = 9,5mm
Slave ~22mm s r = 11mm

Original force ratio and some estimates with different master sizes:

19mm master: 11*11 / 9,5 *9,5 = 1,34
18mm master: 11*11 / 9 * 9 = 1,49
17mm master: 11*11 / 8,5 * 8,5 = 1,67
16mm master: 11*11 / 8 * 8 = 1,89


Additions to master cylinder size catalogs:
Wilwood
http://catalogs.wilwood.com/2008_Tech_Catalog.pdf p 110

Tilton
http://www.tiltonracing.com/content....ist2&id=24&m=b

The master blaster bible of different piston sizes
- mix and match master cylinder piston sizes
- the document might need a safety mirror address, please make and link it here
- thanks for the finding of the catalog goes to chief engine builder

http://www.atap.com.au/documents/HYD05.pdf 686 pages


Edit:
The .625" Alcon version was not ok for 200. Pedal environment is also different compared to S2. 0.700" Alcon non offset model (straight flange) is now test driven in 200 20v and ok. Clutch with sachs race pressure plate ...707 is very nice to use. If straight flange model is used in s2, the help spring systems need to be ripped away. Much work. Therefore the recommendation to S2 is pending. The offset in S2 version should be such that the incoming and outgoing pipes are at 10:00 in the offset flange version. AP version offset is at 14:00 position.

[david]

gearbox

Hi all,does anyone knows whether Rs2 engine will bolt STRAIGHT onto 3B GEARBOX.

[pasbogdan]

dm plate kit does not fit sm fly.The difference between discs is about 1-2 mm(visual)Recived today 3b clutch disc.With the 3b disc on fly and plate bolts loosen the space between plate and fly is about5 or 6 mm.When you pull in the bolts,the middle of the plate(the sun how we call it) touches the disc springs. This is not good.Had to buy 3b/rr palte too.
Disc and plate from dm flywheel will work on sm fly but you'll have no springs to absorb

[gedu]

From what I have gathered AAN unsprung clutch disc might be usable with 3b flywheel. At least SRE lists 3B and AAN clutch discs to have same "hub-profile", 0,2mm difference in friction material.

[Losgard]

Never heard of changing master/slave cylinders to others?
3b wheel + sachs 707 + sinter = win.
Loosen engine mounts when putting together, the motor needs to come back a bit because thinner flywheel.
Like someone says, take away like 0.1-0.02mm of the wheels surface and check for diffrences, not more than like 0.02mm is OK.
Measure it on the outside of the surface.