well its 4am and i been chatting with Rosko about different clutch setups. We got to looking at a CNC slave cylinder made for a volkswagon that was retrofitted onto an H2D setup by R&D auto



this seemed pretty neat to me being that they are only slightly more expensive than the slave cylinders that you purchase at autozone, etc.

He told me to look up hydraulic throw out bearings as well. Basically you get rid of the slave cylinder and shift fork all together and run the hydraulic line straight to the throwout bearing.

something like this:


main problem you arrive at here is finding one with the right dimensions so that it will physically mount in place and long enough bearing travel so the clutch will actually engage/disengage properly.

any thoughts? I know some of us that race at the strip would love to be able to get into gears easier and faster than we currently can.

 

yeah I'm gonna have to find a tranny bellhousing and cut a window in it and measure how much travel that bearing needs.

I would think that every other dimension would be adaptable by either adding a spacer to the back or machining some material off. Or if the center diameter is too small a sleeve could be made to take up that slack.

I just had a tranny housing I threw away too

 

it's been awhile since i dug into our clutch housing but you said there was also a threaded hole to maybe use to mount the bearing?

 

yeah it would be the threaded hole where the pivot ball mounts to for the clutch fork. with the hydro throwout you wouldn't need that ball there so it would free up that hole to mount whatever there. might be a little too far out of the way though for the bearing to reach.

 

Well, that's one step farther from just removing the stock hard line and Damper and replacing with the SS Line..

I might have given this a shot if it had come up about a month ago.. As I had to replace my entire clutch system. Master, Slave, and Line...

But I will say one thing, I can not figure out how that thing works...??

I do notice that it hooks up on the opposite side from stock.. And it looks like it's going to PULL instead of Push like the stock system does... Which, with it being mirror to the stock setup, would be correct..

Just what's go me is how is the Fork going to be Pulled backwards with a Hydraulic Slave that, if it works like the Honda Slave, normally pushes??

Or is that how the VW's work??


Heh if you don't understand what I'm saying.. Eh... I'll try and re-word what I'm saying..

 

Maybe I don't understand. What's the benefit of upgrading the slave cylinder if you leave the rest of the clutch sys intact? I can see a little benefit with the hydraulic throw out bearing as it's more precise and less prone to failure in some situations.

As for being able to bang gears faster you'd do better to reduce the MoI of the clutch itself. The synchros are used to accelerate the gearsets to match the speed between them. With large diameter clutch disks the synchros have to work harder to absorb the energy of the disk spinning at 8000+ rpm before the gears can engage.

Tilton and Clutchmasters etc. offer lightweight, multi-disk clutches that are a smaller diameter so that you can shift easier at high rpms. They add multiple disks to increase the holding capacity but there are benefits of just having lighter/smaller clutch disks that go overlooked in NA applications.



The Tilton cerametalic FW/clutch package drops over 20 pounds off the H22 rotating assembly and both clutch disks are lighter than a single OEM sprung unit as well as being smaller diameter. Get a smaller diameter clutch, your synchros will love you for it.

I thought about modifying a custom Hayabusa dry clutch to work with an H/K series gearbox but never got too far with it. They're like 4.5" diameter and designed to hold 400+ hp boosted drag hayabusas. Should be able to hold 250whp on a NA H22/K20.

Pirate

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rosko &raquo;</TD></TR><TR><TD CLASS="quote">yeah I'm gonna have to find a tranny bellhousing and cut a window in it and measure how much travel that bearing needs.

I would think that every other dimension would be adaptable by either adding a spacer to the back or machining some material off. Or if the center diameter is too small a sleeve could be made to take up that slack.

I just had a tranny housing I threw away too </TD></TR></TABLE>

I have 4 H series trannies in my garage and would love to donate one to a test!
FREE picked up in Chicago!

 

what would be the point in changing it. short the distance quicker shift/engagement? i dont understand the current setup seems to work fine.

 

find a way to make it more precise and smooth. shifting the stock tranny at 8200 isnt exactly the easiest/quickest task at times, lol.

 

I wouldn't want to mess with the hydraulic throw out bearing, that just seems like you're asking for trouble, no? I mean if something hydraulic goes wrong, how are you going to bleed it w/o removing the trans, and if the thing goes bad some way it's going to soak your clutch in brake fluid.

Is that pull type slave cylinder "faster" than our push type?

I'm in with Pirate, those tilton clutches are sick, though they cost upwards of $1500 last time I checked. The only argument I would have with that pirate is that 400hp drag hayabusas make a max of about 150lbs of torque depending on their powerband, are you sure one of those clutches would be good for closer to 200wtq which would be even more before drivetrain loss?

good thread blake

 

matt,
I am thinking that the pull type just has a better feel to it. Think like you are at the gym, sitting at the machine doing a chest press. How much weight can you do....k now think about being on the machine where you pull the weight and work out your back. Which position allows you to handle more weight?

kinda an odd comparison but it makes sense to me atleast, lol.

And you could bleed it by extending the bleeder nipple with some braided hosing and mount it outside the casing.

Pirate,
Yes, you have a great point about the clutch, but those are 1000+ dollar clutch assemblies. Don't quite need that for my car yet, lol. Very interesting about the weight droppage. so maybe what i need to look for is a company who makes the smallest disc yet still offers good torque holding.

 

for thinking outside the box.

Something like this is just going to some experimenting it seems like...somebody just buy one and rig it up!

 

so what your saying is:

slave cylinder = miniature person doing a bench press?

maybe we should jsut mount up some hobbits or smurfs and an intercom on our trannies and call it a day

it seems like a pull vs push type slave would net the same exact results, ur just pushing the fluid on the other side of the piston if that makes sense? well atleast thats waht i seems, i have never seen nor driven a pull type car

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">The only argument I would have with that pirate is that 400hp drag hayabusas make a max of about 150lbs of torque depending on their powerband, are you sure one of those clutches would be good for closer to 200wtq which would be even more before drivetrain loss?</TD></TR></TABLE>

Clutches are rated based on torque capacity, not HP.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Eddiebx &raquo;</TD></TR><TR><TD CLASS="quote">
it seems like a pull vs push type slave would net the same exact results, ur just pushing the fluid on the other side of the piston if that makes sense? well atleast thats waht i seems, i have never seen nor driven a pull type car </TD></TR></TABLE>

I agree that the fluid is going to net the same results, but if buckling of the system/shafts, or connections is part of the slop, then that should be improved with a pull system.

This is an oversimplification of what I'm trying to say, but: "Its easier to pull w/ a rope then push."

Either way its a unique idea and I like that

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">matt,
I am thinking that the pull type just has a better feel to it. Think like you are at the gym, sitting at the machine doing a chest press. How much weight can you do....k now think about being on the machine where you pull the weight and work out your back. Which position allows you to handle more weight?

kinda an odd comparison but it makes sense to me atleast, lol. </TD></TR></TABLE>

Its still the same amount of force needed, though the way our muscles are set up the second scenario is easier.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">
And you could bleed it by extending the bleeder nipple with some braided hosing and mount it outside the casing.
</TD></TR></TABLE>

true.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">
Pirate,
Yes, you have a great point about the clutch, but those are 1000+ dollar clutch assemblies. Don't quite need that for my car yet, lol. Very interesting about the weight droppage. so maybe what i need to look for is a company who makes the smallest disc yet still offers good torque holding.</TD></TR></TABLE>

agreed.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Finest &raquo;</TD></TR><TR><TD CLASS="quote">

Clutches are rated based on torque capacity, not HP. </TD></TR></TABLE>

uhh yeah, so read my post again, I would not have gone thru the torque numbers if I hadn't known that.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">The only argument I would have with that pirate is that 400hp drag hayabusas make a max of about 150lbs of torque depending on their powerband, are you sure one of those clutches would be good for closer to 200wtq which would be even more before drivetrain loss?</TD></TR></TABLE>



BTW on this talk of clutches, I fit up my braided stainless earl's -3 an line and all today with my new master cyl....mmm tasty. pics are coming

I figured out what the "damper" does. All it is is just a tiny reservoir with the outlet bigger than the inlet, the alleviate some of the hydraulic pressure necessary. Good idea honda. The thing was leaking like a pig though, in fact, not just there, but there was a another spot leaking. no wonder my clutch was always sketchy.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">BTW on this talk of clutches, I fit up my braided stainless earl's -3 an line and all today with my new master cyl....mmm tasty. pics are coming

I figured out what the "damper" does. All it is is just a tiny reservoir with the outlet bigger than the inlet, the alleviate some of the hydraulic pressure necessary. Good idea honda. The thing was leaking like a pig though, in fact, not just there, but there was a another spot leaking. no wonder my clutch was always sketchy. </TD></TR></TABLE>

^^ Same problem, but mine was the Slave.. But didn't know it when I first did the swap.. Found out a weeks after the swap that it was the Slave. Freakin' worst part was I replaced the Master & Slave Cylinders, but the New Slave's Bleeder Screw broke in half when I was bleeding the system... So I just put my old one back on... Then Fluid started pouring, not leaking, pouring out of the back of the Slave... Back there again doing the work.. Bah!

I had so many more problems with that freakin' job.. It was so depressing.. All I could hear in my head was "Don't fix it if it's not broke."

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">The only argument I would have with that pirate is that 400hp drag hayabusas make a max of about 150lbs of torque depending on their powerband</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Finest &raquo;</TD></TR><TR><TD CLASS="quote">Clutches are rated based on torque capacity, not HP. </TD></TR></TABLE>

Seems that various boosted Hayabusas make between 120 and 250wtq depending on pressure/mods.

http://www.efrracing.com/dynographs.html

Like I said. I looked into it but I've no time and enough projects. A custom FW/bike clutch package/clutch plate actuater would probably be as expensive as a tilton setup. Lord knows what the clutch life would be too. It's not real easy to get to the damn thing either. Drop the gearbox every 1000 miles? No thanks, at least not on a Prelude.

And Matt, it's only money. We're young. We'll make more.

 

OP: The setup you pictured neglects one thing. Slave cylinders don't have alot of travel, so any flex in the system is important. You've got the cylinder mounted to a couple pieces of what look like bent steel with no gusset. This is significantly less rigid than the stock unit which mounts to the transmission case. The mounting rod for the cylinder is also bent, which means it will bend very slightly every time the clutch is used, regardless of whether it is pushing or pulling.

Thumbsup for effort and innovation. But before everyone runs out and copies this, it's not a performance benefit. If you want a shorter or stiffer clutch feel you can play with the sizing of your master and slave cylinders, or your flex line, that's where any difference in feel in this system is going to come from.

 

^^ thats not his setup btw.

Blake I just looked at the bellhousing and I don't really see a good place that that thing could be mounted too. the bellhousing on the h-series trannies is bigger therefore the rest of the casing is offset a little further away than that d-series one.

 

You people think too much.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94Vtecluder &raquo;</TD></TR><TR><TD CLASS="quote">You people think too much. </TD></TR></TABLE>

No such thing....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94Vtecluder &raquo;</TD></TR><TR><TD CLASS="quote">You people think too much. </TD></TR></TABLE>

You don't think enough.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rosko &raquo;</TD></TR><TR><TD CLASS="quote">^^ thats not his setup btw.

Blake I just looked at the bellhousing and I don't really see a good place that that thing could be mounted too. the bellhousing on the h-series trannies is bigger therefore the rest of the casing is offset a little further away than that d-series one.</TD></TR></TABLE>
just machine a billet adaptor duh