17 replies to this topic

[PuddleSkipper]

Sorry, I meant to post this under technical but am not sure how to change it.
I messed around with some stuff at the junkyard and was wondering if the clutch master cylinder could be mounted to the firewall in the clutch cable hole location, if anyone has done this and could point me toward a thread I would be very grateful! Here are pics, The master cylinder does clear the power brake booster, but doesn't fully insert into the hole because of the clutch cable alignment brace/anchor. The other obstacle is that on the hydraulic clutch the clutch pedal pushes forward while on the cable clutch it pulls backwards. I thought about using something like a Z bar like on the Dodge/Plymouth clutch set up to transfer the backward direction of the cable clutch pedal to the forward direction needed to push on the master cylinder rod. Maybe someone has done this or has a better solution? It'd be nice not to reinvent the wheel. Heres the pics, they were taken on a CRX, 3G is a little different firewall but when I looked at my 3G it was almost the same with the same relative postition to the brake booster:

Edited by PuddleSkipper, 18 January 2012 - 04:46 PM.

[PuddleSkipper]

Here's pics of the 84-87 civic manual clutch pedal setup I reposted from my 87 si d series swap.

Bottom left is what I was talking about for the clutch cable alignment brace/anchor

[PuddleSkipper]

more pics




And heres a diagram with the Z bar, pictured in the center, as the pedal is pushed the pedal rod pushes on the top of the Z bar which pivots at the center, the fork rod on the bottom is driven backwards to the release fork

Edited by PuddleSkipper, 18 January 2012 - 04:43 PM.

[chedda_j]

Looks a little hogging and you could get that to fit into the stock location. The firewall won't be strong enough for the pressure from the push rod set up, so you will need to reinforce it with a piece of sheet metal, either on the front side or backside. I think you would be able to use a brake pedal in replacement of the clutch pedal as both work the same way. You will need to modify the pedal, maybe the entire assembly, and make the pivot further up the pedal box to align it with the slave cylinder. You will also need to add a pedal limiter, return spring, and a custom pushrod. You may want to make the push rod adjustable by having a long nut in the center just for fine adjustment.

[anjin]

Probably easier to get a whole hydraulic pedal assembley and put it in. Mounting holes likely will be the same from my experience with the brake assembleys.

[PuddleSkipper]

Probably easier to get a whole hydraulic pedal assembley and put it in. Mounting holes likely will be the same from my experience with the brake assembleys.

I already looked at that. Yes the brake booster holes are the same but it gets kinda sketchy after that cause the firewalls are different which means different mounting position/angle of the anchor bolts, the cable entry points, length of pedals, possibly other things. I guess I should have posted this pic sooner. The master cylinder is located lower on the firewall than the hole on cable clutch. This is because the pivot point is at the top of the pedal and the master cylinder attaches in the middle of the pedal arm so as the pedal is pushed down it pushes the master cylinder rod forward. If the car is an automatic the hole in the firewall is simply covered with a block off plate.

Sorry, I don't have a side view, but on the 92-95 the clutch pedal assembly is separate from the brake/gas pedal. Maybe next time I go to the shop I can snap a side view.


My idea was simply to modify the existing pedal housing that way everything would be bolt up instead of trying to figure out multiple angles - was kinda looking for a simple well thought out solution, hoping somebody has already done this. I am also on kinda a time bind, maybe I will take like one crack at it, if it doesn't work then I will move one and post what I did so someone else can build off it.

[kaymo]

why not convert the transmission to cable actuation? personally i like a cable better. a clutch master and slave are just extra things to go wrong. as are lines and fluid. a cable has one fail point, and one replacement piece. and its easily adjustable. the main reason i like however is pedal feel. its much better than hydro clutch IMO

[chedda_j]

why not convert the transmission to cable actuation? personally i like a cable better. a clutch master and slave are just extra things to go wrong. as are lines and fluid. a cable has one fail point, and one replacement piece. and its easily adjustable. the main reason i like however is pedal feel. its much better than hydro clutch IMO

We need like buttons.

I personal love the feel over a cable trany over a hydro as well. You can feel the clutch slip and grab.

[PuddleSkipper]

why not convert the transmission to cable actuation?

I have the hasport CMA adapter, which I think is pretty much what you are talking about. Or maybe your talking about the lever set up? They don't make a lever setup for this swap, so either way I will be welding something. I thought this would be a cleaner look and less parts than the CMA adapter. I would like my swap to look stock, like the car came from the factory that way.

Also thanks Chedda for your imput

Edited by PuddleSkipper, 18 January 2012 - 11:48 PM.

[kaymo]

if you want it to look factory, then put a cable in. hydro setups were usually used for heavier clutches back then... all the hondas used cables. it wouldnt be hard at all to change the slave cyl to cable actuated. a well designed bracket should do the trick and can be made to look stock. the actuation of the clutch is the same motion whether hydro or cable, its just less BS to mess with when using a cable. im assuming this is a B series swap? i always hear of people swapping hydro trannys for cable trannys just to make it go with their car.... always wondered why no one just fabbed a damn bracket and called it a day....

[anjin]

For the B swaps the hydro boxes have stronger synchros, and it's easier to get the 4.9 final drives and close ratio gear sets if you go that direction. Plus spare parts are easier to get. Long term a hydro box with the cable conversion is likely where I'll go.

Puddleskipper - thanks for the feedback on the pedal set-up. If I get the chance I'll take a couple of pictures of the clutch pieces in that swap I mentioned.

[PuddleSkipper]

i always hear of people swapping hydro trannys for cable trannys just to make it go with their car.... always wondered why no one just fabbed a damn bracket and called it a day....

I am doing the D series swap with the AFD2 Hasport mounts designed specifically for the Hydro tranny. I have no idea if these mounts can be used with a cable tranny. This is an mpg swap which means it will be a D15Z1 (actually a JDM D15, similar) with the D15Z1 tranny with hopes of getting 50 mpg or better. And I believe RTM did exactly what you are talking about .....
You Want To Put A 88+ Dseries Into A 1g/3g

Puddleskipper - thanks for the feedback on the pedal set-up. If I get the chance I'll take a couple of pictures of the clutch pieces in that swap I mentioned.

Thanks for the info on the hydro stuff, any info regarding the pedal stuff would be much appreciated. My idea is to weld a pipe across the top of the pedal parallel with the bolt that both the clutch pedal and brake pedal pivot on. This will be my new pivot point. On this pivot point I will make a half circle tab that is slightly offset, this will act like a rocker arm, I can increase the ratio in my favor that way. The Clutch Master cylinder already has an adjustable rod. I will have to put an adjustable rod linkage between the pedal and the Z bar/rocker arm pivot point. Forgive my artistic skills but it would look like this:


I think this would be a simpler setup and would look stock unless you started digging under the dash, all the modifications would be to the pedal assembly and if someone wanted to go back to the cable set up, swap out the pedal assembly and plug the two holes on the firewall that were drilled in there for the clutch master cylinder. There is of course drawing it out on paper vs actually doing it.

Edited by PuddleSkipper, 20 January 2012 - 02:21 AM.

[PuddleSkipper]

I think I am going to roll on with this, if anyone has any helpful imput that would be great. Obviously I need to measure it out and check where the wire harness and whatever else might be in the way. If it doesn't work out it doesn't work out, I can snag another pedal set up from the salvage yard no problem. Need a good chunk of shop time, but I don't think it will actually take that much time. Well see............if it fails I'll post it here, if it suceeds I will post it as a new thread with what I did with lots of pics. If it suceeds chances are you will also see it in my D series swap.

[Bubba]

Looks like it could work- just try to make the pivoting rocker arm as long as possible so that it doesn't bend the slave cylinder rod up and down as much as it travels from one extreme to the other.

[PuddleSkipper]

Looks like it could work- just try to make the pivoting rocker arm as long as possible so that it doesn't bend the slave cylinder rod up and down as much as it travels from one extreme to the other.

I think the clutch master cylinder rod is attached by some sort of pivoting joint, maybe ball and socket? Anyway from the 92-95 civic stuff when the rod is pushed forward it keeps the same path forward but the angle of the rod in relation to the pedal changes, just like connecting rods driving the piston. I should be able to use the rocker set up because of this. When creating the pivot arm, although I would like to play with ratio of the rocker, pedal side vs master cylinder side, but I need to keep in mind that there is a range of motion on the clutch master cylinder rod, or the leeway up and down. I can use the periodic function I learned in my Math 112 class to calculate the distance the rod moves forward/backward (definately forward) in relation to its up/down movement (definately down). Based on the range of motion for the rod I can pick a radius that moves the rod far enough forward without going beyond the range of motion. Because this is in a straight line(the pedal arm is straight and clutch cable hole is centered on the pedal arm) and on the same plane of reference, it shouldn't be too bad and I shouldn't have that hard of time fabing the parts needed.