KE70 Clutch -> Hydro

[blinded]

Hey guys,

Currently doing a 4AGE into my KE70 at the moment and I am up to the exciting part of converting to a hydraulic clutch setup!

Now, I know the obvious route to take is to fit an AE71 pedal box, or a t-18 with minor mods, but I am deciding to modify the original KE70 box to use the clutch master cylinder I have here from my donor AE86 as I'd rather not pay the $150 + that most people want for the AE71 setup and also, from my first assessment, I should be able to make the KE70 pedal box work easily.

Firstly, here is how I plan to do it:

http://www.ae86drivingclub.com.au/dcimages/1/6/6/63875.jpg

From what I have seen, with the clutch MC mounted in the factory position (mould in firewall), the pushrod comes through 'X' amount out of line from the clutch pedal and clears cabin parts, so it can move in and out with no obstruction from anything. See below:

http://www.ae86drivingclub.com.au/dcimages/1/6/6/63876.jpg
http://www.ae86drivingclub.com.au/dcimages/1/6/6/63877.jpg
http://www.ae86drivingclub.com.au/dcimages/1/6/6/63878.jpg

The measurement 'Y' is the range needed for the clutch to work. Pretty much fully extended (clutch disengaged) to fully depressed (clutch engaged). Now, by knowing the range of the master cylinder pushrod, I can work out the position of where it has to mount to the clutch pedal so that when the pedal is depressed, the travel of the master cylinder pushrod is correct. Common sense shows that by having it mounted closer to the line of the pivot point, the travel of the pushrod will be less, and obviously making it further from the pivot point will increase travel. Find the 'sweet spot' and pushrod travel should be the same ratio to the pedal travel.

From here, all I need to do is just make an 'L' shaped new bracket that connects the clutch pedal to the line of the master cylinder and mount the pushrod into it so it travels the correct distance to engage the clutch. Obviously this bracket will be inline with the master cylinder in both axis so that the pushrod slides in straight.

At the moment I am yet to make the new bracket for the pushrod to mount off, but I just wanted to post this up to see what everyone thinks of my current plan before I get too carried away :yeah: Also open to any suggestions you may have!

I will make sure to keep this updated as to let people know how it goes, and hopefully if it works according to plan, people may be able to copy it as an alternative to the AE71 Pedal box :)

[Skylar]

I don't like your L-shaped bracket. Do as per right bracket and triangulate back (or forwards if you can get the welder in there) or make bracket per drawing on left.

16455

[blinded]

The plan is to get the 'L' bracket in the correct spot, then gusset the inside corner where it meets the pedal. That way it will be held on with 3x the welds, and also should stop any flex when the pedal is depressed (being on the 'inside'). Also I have removed the whole pedal assembly already so I can do the welding outside the car! Just have it in there at the moment so I can make some measurements then I'll re-take it out again.

I'll see how it goes first with the 'L', but I must say I like the idea of the first bracket you drew. Only thing is I don't know if space will permit it. I think it may hit on the pedal assembly where the pedal pivots from. (if that makes sense) Will have another look at it tomorrow and see what I can do.

Do appreciate the info though!

[sam2306]

looks like a good idea man,
one question do you have to remove any of your dash to do this? like you do when put in an ae71 pedalbox?

[blinded]

http://www.pixorhost.net/upload/ulm179wpup8b9wpm6nlnljc21d69gx5ai4fscc17tcbzwdmw1x .jpg

You could probably get away with not having to remove the pedal box like I am if you were to try do all the welding inside the car, but I pulled the whole thing apart to remove the pedal box to make it easier.

[Skylar]

Yah, if you have the space, do a bracket that's the combination of the two, just so it looks like it'll never break. Just make sure you triangulate it rather than a simple shitty "L" bracket.

You only need to weld onto the pedal right? Why pull the whole pedal box? precise measurements?

[Nikkojoe]

Just a qestion, will the firewall flex because the pedal box does not cover that area around the MC to reinforce it? Last year a guy I was helping do his 4age into ke70 tried doing something similar to what you are doing which looked like it was working (without load of clutch) but once the engine and box were in and clutch hooked up it failed within a few tests (and clutch kicks). He had a pedal box but cbf doing the swap, but ended up doing it.

[lolwat]

you DO NOT!!!!!!!! need to remove your dash to put ae71 pedal box, why does everyone do that i didnt

and as said above, reineforce it, as you will be suprise how easy it will brake wyhen you smashing your clutch

[blinded]

Well, after some very fucking awkward measuring, I worked out the position of where the bracket had to be welded to the pedal.

Tacked it on and tested it...

...Couldn't believe it, it actually was in the correct spot! :D

Didn't worry about bracing the 'L' Bracket as I ended up rotating it 90º so that the weld runs inline with the travel of the pedal, as opposed to how I had it drawn with it being perpendicular to the pedal. Obviously time will tell, but it seems like it will hold fine.

So yeah, measurements are below for anyone who wants to try it. These were taken with the clutch pedal in the 'disengaged' position. (ie. If you had no foot on the pedal)

http://www.ae86drivingclub.com.au/dcimages/1/6/6/63955.jpg

And how it looks from a few angles:

http://www.ae86drivingclub.com.au/dcimages/1/6/6/63956.jpg
http://www.ae86drivingclub.com.au/dcimages/1/6/6/63957.jpg
http://www.ae86drivingclub.com.au/dcimages/1/6/6/63958.jpg

Obviously I can't test this 100% at the moment as I don't have the T50 in yet, but I have full travel of the clutch pedal and the MC pushrod has the same travel as it did when it was in the sprinter, so theoretically it should work...

Will see how fire wall flex goes too. That was one thing that didn't even occur to me when I did it. I have never seen an AE71 pedal box before thus didn't know it braced the firewall. If flexing is an issue, it should be a piece of piss to make a bracket that goes from the firewall behind the booster to where the clutch MC mounts. Will see how it goes first :)

[FAST EDDIE]

looks good!

[blake.]

thats awesome! top work.

[blinded]

Okay, I know it has been a while since I updated this, but I have only recently bleed the clutch and been able to drive it.

So far from my minimal driving, there seems to be no issue with the firewall flexing etc. Obviously it may change when it is getting abused/kicked, but I will report on that later. For the moment though, with normal driving, it operates perfectly :)

My only change (personal preference) will be to replace the standard pedal return spring with a slightly stronger one. The stock one works fine, but I'd prefer if the pedal felt a bit more firm/harder to press.

[sld sho]

would you be intrested in makeing another one of these?

[nichy]

old thread i know but any more info on this ?

did you end up having to make a new brace for the fire wall?

will be trying this on mine

[Nikkojoe]

I know someone who recently did a setup like this and the firewall cracked after a track day. Had to hammer the firewall back in and brace up the master.

Do it once, do it right. Just get the right pedal box!

[blinded]

Updating as I re-found this thread. Sorry for the late reply Nichy (if you even see this :))


Still running the above pedal box. Have done a track day at Winton in the mean time, as well as heaps of 'normal' driving.

No issues at all yet. Will report back if there happens to be.

[MickStephens]

I know this is a massive thread dig, but I thought id ask my question here instead of starting a new thread.

I am by no means a mechanic or very mechanically minded. Can anyone explain to me why when converting to an 4AGE engine in a KE70 do you have to convert to a hydraulic clutch also?

This is probably a very novice question, just wondering. Is it simply because the gearbox you use with a 4AGE must be hydraulic assisted and cant be used with a cable?

[Matt]

Because the box behind the ke70 will not bolt up to a 4age block and the bellhousings can't just be swapped over.

the fork setup behind a t50 doesn't accept a cable.

you could perhaps make something which holds the clutch cable in the correct place with a custom fork and not swap it I guess

[jdm86gtz]

Flo in Ireland offers this for 4AGE powered KP61 Starlets so it should work in a KE also

http://flos.ie/index.php/product/t50-cable-clutch-conversion-kit/

[LittleRedSpirit]

Lets spend a bunch of money to downgrade to a cable clutch. 120 pound plus freight its cheaper and gives you a better result to buy an ae71 pedalbox and go hydraulic. No ripping out the gearbox to reconfigure everything either.