LS1 Hyd Slave Cyl

[mateo m3]

I went back/forth with Mike Collins on the design he had his machine shop do the brackets. These are some pics of the early bracket and 13/16" MC, I now use a beefier bracket and 7/8" MC.

any picture of it install?

[BRAAP]

Stumbled upon some really good info regarding the LSx clutch and shimming the slave cylinder. The LSx clutch system is a finicky set up that requires fore thought and attention to detail to be sure it will function correctly.

Shimming the slave is one area that confuses a lot of people as they are not sure why it is done or if they need to or not. These two links below cover "why" it is done and "how" it is done correctly to get the desired results.
Be sure to read BOTH of these links. I cut and pasted the first post of the first thread below.

http://www.ls1tech.com/forums/manual...need-shim.html

http://www.ls1tech.com/forums/manual...good-tech.html

I get a ton of PMs from guys asking if their clutch setups need to be shimmed and when I suggest measuring to be sure, their first response is usually "how?" To be as helpful as I can to everyone, I'm going to try and describe the measurement process. It's tough to do without pictures, but try and follow me here:

During your next clutch install, determine if your slave cylinder needs to be shimmed or not. To do so, you need to take two measurements:

1. Measurement "A" is the distance between the surface of the bellhousing that meets the transmission to the tip of the pressure plate fingers. To get an accurate measurement, the clutch must be torqued properly.
   
2. Measurement "B" is the distance between the throwout bearing surface to the transmission surface that meets the bellhousing. To get an accurate measurement, the slave spring must be removed and the bearing must be fully seated at the bottom of its travel; resting on the slave's base.

Once you've got your two measurements, make sure that measurement "B" is ~1/16" to 1/8" LESS than measurement "A". If you come up with more than 1/8", add an appropriately sized shim between the slave and the transmission in order to get the measurements where they need to be.

If there is no difference between the two measurements, or if "B" is greater than "A", there could be a problem with clutch engagement which could result in premature clutch slip and eventually a total failure.

Here at Tick Performance, we're always in pursuit of new ways to get you guys shifting as quickly & efficiently as possible. Determining if your setup needs a shim or not is quick, easy and cheap way to ensure proper function and long life out of your next clutch.

Good luck guys!

Hope that helps,
Paul

[BRAAP]

Break through regarding the LSx clutch line with the BMW Master Cylinder.

No special fittings/adapters needed. The GM braided clutch hose can fit the BMW master cylinder with just a small massage on the GM fitting, then it fits perfect and the GM line is already the PERFECT length! I'm surprised no one else saw this or even looked into it yet?!

I just posted the details in my build thread here;
http://forums.bimmerforums.com/forum...3#post19369453


Here is shot of the GM clutch line installed in the BMW clutch master cylinder;

[rao]

Neat

[mateo m3]

I just purchase a clutch line from speedway i wonder if it will work this way

[BRAAP]

If it is an OE replacement F-body clutch line, I don't see any reason why it wouldn't work.

[Pzary3233]

Now I need to befriend the guy next door with a lathe!

Awesome! Thanks!

[rao]

Or you can buy the BMW master cylinder with a traditional brake line fitting

[Pzary3233]

^ making the part sounds like a lot more fun then buying something...

though the probability of failing is much higher!

Which master cyl should one be looking for?

[rao]

The "later" one post 10/94 for 6 cylinder e36s and all 95+ M3s Part Numer 21-52-1-162-303

[mateo m3]

If it is an OE replacement F-body clutch line, I don't see any reason why it wouldn't work.

this is the part # 51513948 of the line i got from speedwaymotors.com

[BRAAP]

Or you can buy the BMW master cylinder with a traditional brake line fitting

The "later" one post 10/94 for 6 cylinder e36s and all 95+ M3s Part Numer 21-52-1-162-303

You meant a different M/C right? In looking over that particular M/C, it is the same one I pictured above in my '97 M3, with its O-ring style, clip pin retained connection, not really a traditional brake line fitting.

this is the part # 51513948 of the line i got from speedwaymotors.com

That clutch line is not an OE replacement line as it has a dash-4 threaded end. OE lines had the GM quick disconnect on one end and the O-ring fitting I sketched in A-CAD in my build thread. For your line you will need a fitting that male dash-4 on one end to female 10mm x 1.0mm ISO bubble flare on the other, (may take two fittings to get this orientation). Then that wil connect directly to the BMW hard line with LOTS of extra braided clutch line looped around.
Hope that helps.

BTW, filled and bled the clutch line tonight, clutch pedal feels great, NO leaks.

[bmwguru]

You meant a different M/C right? In looking over that particular M/C, it is the same one I pictured above in my '97 M3, with its O-ring style, clip pin retained connection, not really a traditional brake line fitting.




That clutch line is not an OE replacement line as it has a dash-4 threaded end. OE lines had the GM quick disconnect on one end and the O-ring fitting I sketched in A-CAD in my build thread. For your line you will need a fitting that male dash-4 on one end to female 10mm x 1.0mm ISO bubble flare on the other, (may take two fittings to get this orientation). Then that wil connect directly to the BMW hard line with LOTS of extra braided clutch line looped around.
Hope that helps.

BTW, filled and bled the clutch line tonight, clutch pedal feels great, NO leaks.

This is the fitting everybody needs. I got it from speedway motors. The part number is 6174044. Its a male -4 on one and and male european metric 10mm 1.0 on the other end. They come as a pair for $18.99 Here is a link to the catalog page they are on. They are about halfway down the page. http://www.speedwaymotors.com/AN-to-...ters,6462.html It should look like this This will work with the "early" pre 10-94 production master cylinder as they use the plug in quick dis-connect style but they come from BMW with an adapter that plugs into the master and has a female metric 10mm x 1.0 bubble flare thread. Unfortunately that piece isn't available from BMW separate, you have to get a complete master cylinder. The pic in Realoem.com is the same for the early and late master cylinder. Niether pic shows the adapter that comes on the early style. I have both an early and late master cylinder that I can take pics of to compare if anybody is interested. The BMW part number for the master with the adapter fitting is 21526758830.

[mateo m3]

please post pics

[BRAAP]

please post pics

Who are you asking?
What do you want pics of?

[bmwguru]

Who are you asking?
What do you want pics of?

He's talking to me. I am going to post pics of the BMW master cylinder with the plug in quick dis-connect and the one with to BMW adapter that allows the use of a standard metric bubble flare connection. I just have to dig up my camera.

[BRAAP]

Cool, thanks. Looking forward to seeing those pics.



Forgot to mention earlier that in a quick measurement of GM F-Body clutch Master Cylinder and the BMW clutch Master Cylinder, they are actually quite similar in design, and dimensions. Both attach on a similar angle in the car, similar distance from push rod end to firewall mount, similar OD of the plastic body... When I say similar, I mean ballpark, not a direct bolt in. Looks as though if someone really wanted to, the F-body master cylinder could be installed in the BMW making the clutch line connection that much easier. My guess is it is far easier to just shave .020" off the OD of the GM clutch line fitting and just slip into the BMW master as I did.

[Matt Arruda]

I dont want to hi jack the thread but has anyone had issues with the stock pedal assembly. I broke the stock clutch pedal on my E30 with T56 and a heavy PSI plate. Anyone else expeirence this?

[BRAAP]

Wanted to follow up with some more info you all may be interested in.

Both GM and BMW used a restrictor in the clutch hydraulic lines that for most is more detrimental than good, especially if you like to drive spiritedly.

GM’s version is just simple restriction in the braided flex line, the fix is dubbed “The drill mod”.

Here is a video from Centerforce on the drill mod;
[ame]http://www.streetfire.net/video/centerforce-shows-the-drill-mod-for-ls-series-hyd_718568.htm[/ame]

Here is the Install University “drill mod”, starting at bullet 16;
Click ME for the Install University LSx "drill mod".


BMW employed a similar device on many BMW’s called the “Clutch Delay Valve”, (CDV). This BMW clutch line restrictor is a fitting inline on either end of the flexible clutch line hose in the E36, looks like a extra coupler/fitting. If using the BMW clutch hard line from the M/C, just be sure it isn’t on the end of the line when you attach your GM clutch line. Here are some articles on the BMW clutch delay valve;

E36 specific;
Click ME for DIY E36 CDV delete.
Click ME for general E36 CDV discussion.


Covers all BMW CDV's
http://www.zeckhausen.com/CDV.htm
http://www.zeckhausen.com/CDV.htm#CDV%20by%20mail



Recap;
GM line requires drilling out the restrictor, BMW’s restrictor is merely removed.

[Maynor]

Thanks very much for that restrictor info Braap.

[M5Hunter]

Good looking out. FYI my '92 325 does not have this.

[Pzary3233]

The "later" one post 10/94 for 6 cylinder e36s and all 95+ M3s Part Numer 21-52-1-162-303

Or you can buy the BMW master cylinder with a traditional brake line fitting

This is the fitting everybody needs. I got it from speedway motors. The part number is 6174044. Its a male -4 on one and and male european metric 10mm 1.0 on the other end. They come as a pair for $18.99 Here is a link to the catalog page they are on. They are about halfway down the page. http://www.speedwaymotors.com/AN-to-...ters,6462.html It should look like this This will work with the "early" pre 10-94 production master cylinder as they use the plug in quick dis-connect style but they come from BMW with an adapter that plugs into the master and has a female metric 10mm x 1.0 bubble flare thread. Unfortunately that piece isn't available from BMW separate, you have to get a complete master cylinder. The pic in Realoem.com is the same for the early and late master cylinder. Niether pic shows the adapter that comes on the early style. I have both an early and late master cylinder that I can take pics of to compare if anybody is interested. The BMW part number for the master with the adapter fitting is 21526758830.

Ok so 95 M3s came with the 10mm flared fitting Master Cyl Correct? Thus a steel 10mm x 1 to 4an adapter will work with an aftermarket -4an clutch line with the correct fitting on the Throwout bearing end.

How long is the stock line? I'm interested in getting the clutch stuff ordered at the same time as the header stuff.

-Paul

[RahgBag]

Paul, if you look here:

http://www.pelicanparts.com/bmw/cata...pg4.htm#item27

It shows your car as using the kind that requires the retaining clip. If you wanted to, you could just replace it with one from an early e36 with the screw-on type fitting, since we know that the early e36 MC is good enough for use with the LS1 setup.

Alternatively, you could just use your factory e36 hardline with your factory M3 clip-on style MC and get an adapter from the hardline to the -4 line.

FYI, I ended up using a 100% custom line that went like this:

Early E36 MC--->M10 to -3AN coupler--->-3AN female fitting crimped onto 6' of -3AN clutch line--->-3AN female fitting--->-3AN male to male coupler--->Vorshlag prototype TOB

I ended up having to do this overly complicated setup because unbeknownst to me, the Vorshlag prototype kit was NOT built with the proper M10 fitting to use the stock E36 lines. It was built only with AN hardware. Also, I ended up going with this setup to keep the clutch line well away from the headers.

[Thaniel]

Seems everyone is going lots of ways with this. On my car I put an adapter at the end of the BMW hard line, Female 10x1.0mm Metric concave seat to -4 Steel (pegasus part# 3265-19). Then modified the GM line to have a -4 end. Simple easy and needed only 2 parts.

My remote bleed line is here
http://ls1bmw.blogspot.com/2007/06/c...leed-line.html

2 more partnumbers for the -4 to 10mmx1.5 metric adapter are Aeroquip FCM2967 or Goodridge 305-04-35P. WHen I was building my car there were out and seems like I ended up with one or 2 spares when it was all done. So if there is ever a stock shortage again let me know and I can dig through my left over parts.

[Maynor]

Bringing this one back up...

After swapping to a new transmission, my high rpm shift issue never resolved. Its obvious my clutch master cylinder is dying. The stock M3 clutch master cylinder is 3/4" bore. I'm doing what JoeZ and several other LSx conversion folks/Corvette/F-body track guys have done to resolve it once and for all:

A Tilton 7/8" bore master cylinder:



If we can find the room, I'm going to install a dedicated remote fluid reservoir so I can stop stealing from the brake master cylinder reservoir.

I have a theory that due to the design of the shared fluid reservoir pictured here:


..that air is being introduced into the clutch master cylinder system in high-g left hand turns. This might be happening due to the fairly high fluid pickup point the clutch master has to feed from on the brake master cylinder reservoir.

Either way, the 7/8" bore master moves a lot more fluid for high rpm clutch disengagement. I'm hoping I get to put it to the test next Friday at NJMP.

John