V6 2.8 clutch cylinders?

[mr.vman]

Finding more parts. Looking at clutch hydraulic pull cylinders that mount on the engine/bellhousing. Two choices? Speedway pull or Willwood. What is the preferred cylinder? The Willwood appears to have a longer stroke? Is a return spring needed on the clutch, bell housing arm? Master cylinder sizing for the clutch. What diameter master cylinder is needed for the pull clutch? Is the diameter of the clutch master cylinder; 5/8 inch or 3/4 inch? Hose sizing, use a -3 flex line or -4 (clutch lines should be -4 but there might be success with the -3 line). For the hydraulic line out of clutch cylinder, out with 90 degree or? I know several questions, need assistance sometimes. Thank you in advance. Steve V. V6 in Arizona

 

[Barry]

Finding more parts. Looking at clutch hydraulic pull cylinders that mount on the engine/bellhousing. Two choices? Speedway pull or Willwood. What is the preferred cylinder? The Willwood appears to have a longer stroke? Is a return spring needed on the clutch, bell housing arm? Master cylinder sizing for the clutch. What diameter master cylinder is needed for the pull clutch? Is the diameter of the clutch master cylinder; 5/8 inch or 3/4 inch? Hose sizing, use a -3 flex line or -4 (clutch lines should be -4 but there might be success with the -3 line). For the hydraulic line out of clutch cylinder, out with 90 degree or? I know several questions, need assistance sometimes. Thank you in advance. Steve V. V6 in Arizona

Steve,

A 7/8" stroke with the $35 Speedway Motors pull cylinder is OK with the stock 5/8" bore Series Alpine clutch master cylinder that most people use. An extra $50 for the Wilwood pull cylinder buys an extra 1/2" of stroke, but it is probably not needed because the pull cylinder will only move as far as enabled by the clutch master cylinder. A stock Series Alpine clutch pedal only provides a stroke of about 1-3/8" to the clutch master cylinder and a stock 5/8" bore master cylinder with a stroke of 1-3/8" will only move a 7/8" bore slave cylinder about 11/16". Do you need more than 7/8" stroke for the pull cylinder? Not with the stock 5/8" Series Alpine clutch master cylinder and not with an 11/16" clutch master cylinder, but a 3/4" clutch master cylinder would result in too much stroke for the Speedway Motors slave cylinder. Is the ability to use larger than 11/16" clutch master cylinders with the Wilwood pull center worth $50? Maybe. Is the Wilwood pull cylinder $50 better than the Speedway Motors pull cylinder? Maybe. Is a purple slave cylinder cooler looking than black? Maybe.

I believe in keeping mechanical pressure off the throw-out bearing which means using a return spring on the bell housing arm. JMO, YMMV.

Seems like you think a -4 hose is better than a -3 hose for the clutch hydraulics. I don't disagree, but will point out that the stock line is probably 1/8" (-2) and is almost certainly not larger than 3/16" (-3). A 90 degree fitting restricts flow more than a straight fitting. A sharp 90 degree fitting restricts flow more than a gradual 90 degree fitting. Does it matter? Not IMO, but YMMV. In this case, what looks right for the fittings probably is right.

As always, your car / your money / your choice.

 

[sunalp]

When doing the last V6 conversion we found the speedway and wilwood cylinders hard to use. It was like using
a stairmaster for one leg! Very stiff. I've heard that the internal slave /throw out bearing is better.
Ask Dan R. He has a lot of experience with these.

 

[DanR]

Barry, Vman is doing a V6 in a "Marco" ?? if I am thinking correctly

A single reservoir Wildwood 3/4 works OK with the wildwood (type) pull cylinder.

Used this "type pull" with my first conversion because it was recommended by the V6 crowd. Lost my clutch once in a most unfortunate time. Rebuilt it with a kit that worked for a couple years, then thought I was again having some problems and went to the Speedway. It has been good for the past three years.

I have had good results with this "pull type" from Speedway.

I try to utilize 3/16" lines in my Conversions.

During the trying times with the pull type from Wildwood, I attempted to go with an internal hyd release bearing. I purchased a Ram Clutch internal unit and started the installation with a very short time line for an up coming British Car Event I really desired to attend...ran into some adjustment difficult and went back to the Speedway and the stock Clutch master cylinder until recently.

I have installed the Ram in another V6 Project that is not yet on the road.....can't give a proper evaluation yet.

 

[mr.vman]

Thank you for the quick responses on this. Use the Speedway pull cylinder with a, 3/4 inch diameter master cylinder. Install a return spring on the clutch lever. Any other recommendations? Steve V.

 

[DanR]

Vman, Don't forget to "cut" the mount hole that the manual clutch cable fasten into on the Mutt II Bellhousing.... it will interfere with the "pull" cylinder operation and alignment.

 

[DanR]

Any other recommendations?

Note that the Bleeder will come from your source in the bottom position and it will not let you bleed the air very well. Swap positions with the pressure and bleeder.... I thought it would not work at first, then tried hoping for the best! It has worked for mine at least the past four years.

If you don't have the Slave cylinder bracket let me know! On another bit of info, try to "sit" your bracket in the back two holes on the "edge" of the engine where the bellhousing come together.....Look in my PDF and you will see what I am referring to.... Click on the GOTO: http://danr.mhartman.net at the bottom of my Signature element for the PDF



Recommend you mount the bracket (silver one) to the extreme rear of the engine not like the brown one.

 

[Barry]

Thank you for the quick responses on this. Use the Speedway pull cylinder with a, 3/4 inch diameter master cylinder. Install a return spring on the clutch lever. Any other recommendations? Steve V.

I thought I was clear when I wrote "..., but a 3/4" clutch master cylinder would result in too much stroke for the Speedway Motors slave cylinder."

 

[mr.vman]

Barry, appoligies on this one, miss read your post. Will order the 5/8 inch master cylinder and pull slave cylinder from Speedway. DanR, I have your mounting bracket for the slave cylinder, need to do some grinding when engine comes out again for more fittings. Thank you for the time and information.
Steve V.

 

[Rockonp04]

You could avoid all those bolt-on applications and just install a McLeod internal throwout bearing. Mine works great and I didn't have to make any brackets.

 

[Barry]

Barry, appoligies on this one, miss read your post. Will order the 5/8 inch master cylinder and pull slave cylinder from Speedway. DanR, I have your mounting bracket for the slave cylinder, need to do some grinding when engine comes out again for more fittings. Thank you for the time and information.
Steve V.

Steve,

If you have a working "factory" clutch MC, it should be a 5/8" bore. You might want to start with it to confirm whether or not that is the best size for your setup (pedal effort, pedal stroke, enough clutch release, too much clutch release, etc.).


Edit:

DanR called to explain that you are working on a Marcos GT (an early '70's "kit car") rather than a Series Alpine. Any working MC with about the right bore size can be used to test the clutch system operation and determine the "right" size. Dan also noted that he has used a 3/4" master cylinder with the Speedway Motors pull cylinder, but the system was adjusted for a "low pedal" and was probably not utilizing the full stroke of the 3/4" MC. As with brake master cylinders, bigger bore sizes result in higher pedal effort.