Maybe set it up for full travel with an adjustable stop so you can set it for only 3/4 or 7/8 or 15/16 or 31/32 or 63/64 travel.
Maybe set it up for full travel with an adjustable stop so you can set it for only 3/4 or 7/8 or 15/16 or 31/32 or 63/64 travel.
Robbie (Forum Supporter) said:but do you want to use the entire stroke on the MC? I think I'd shoot for 3/4 of the stroke or something. Also you need to consider your slave volume and movement distance requirement before you drill that hole. I'm sure you're already planning that
Yeah, unless I'm wrong, Angry is a Brake Engineer by trade. My guess is that he knows what he's doing. I've been wrong before, though. Once. When I thought I was wrong. But I was mistaken.
In reply to Robbie (Forum Supporter) :
Master, slave, and clutch package are all from same year/make/model. Before I ask this next question, let me say that I'm not an expert in hydraulic clutch actuation. Now the question: why wouldn't I want to use 100% of the clutch MC stroke?
My guess would bottoming out the piston/bending rod. Don'no, though.
Clutch MC packaging is a key milestone because it enables brake plumbing, steering column fab, seat location and bracket fab, shifter location and bellcrank fab, all in rapid succession. Last night I repurposed my crib block jig into a pedal box jig:
and started plotting. Audi clutch MC has 10mm ball on pedal end of pushrod, which is typical size for hood and hatch struts, etc. these are same size as used on Boxster shift cables and bellcranks, so I bought several male and female of these a while back. Threads are common M6.
Corvair clutch pedal is slotted for cable attachment, so I raided the solo cup of C4 fasteners again and came up with this:
To get correct motion, the "average" path of pushrod has to be tangent to arc swept by attachment point. With existing point, MC has to be pretty high.
It fits under dash, but inlet port is too high to share fluid with brake reservoir. So today I will lower the clutch MC (it can drop 3.5" from V1) and add a tab to the pedal to achieve my average tangent at the correct lever ratio. I have 2 spare brake pedals to chop up, so it should go fairly easily. LOL famous last words and all.
before I could start today, I walked my 15YO through the oil and filter change plus trans drain and fill (3 qts out of 12 at every oil change) on the Ody:
Came across this on the interwebs wayback machine and.... posted without comment
In reply to Patrick (Forum Supporter) :
Every word of GRM's caption is correct. I had never had the car in 3rd gear before my first drag run. Coolant tubes leaked. 780 double pumper on stock 327 (as received) extinguished the ignition when trying to get on it, etc. was 7 tenths slower than the Corvair-powered car I ran in 2002. Finished 59th out of 66 in 2003 iirc. Got home, pushed it into barn, and ignored it for 4 months. Then attacked and resolved each problem. 16th out of 79 in 2004. Went 13.78@104 (18th) and Alfadriver wheeled it to 18th in the autocross. 15th in concours iirc. So yeah, 2003 was painful. But 2004 was pretty sweet.
Updated Concours strategy:
Updating again before I pass out from the friggin heat and humidity. To lower the clutch MC I had to raise and pull forward the push rod attachment on the pedal. CAD V2 looked pretty promising:
so I transferred it to 14ga and tacked it in place:
and here's another view, just because I'm happy with how it's turning out:
It will get a couple of gussets to stiffen it against push force. that's where I'm quitting for the night. Temp in garage is still 92 and it's humid. Garage faces west, so it's pretty brutal in the summer.
EDIT: ok, I lied. I couldn't go to bed without checking how it all fits in car:
it's (almost) all good. I will have to make clearance for pressure hose fitting at front of MC, shown by red arc below:
But that's a really easy fix. Man, I was dreading this task because I didn't want to face the possibility that it might not work out cleanly. But I'm glad I pulled up my big boy pants and got after it. It's just metal, after all.
Loving the pedal covers.
Worked up a couple gussets in CAD, transferred to scraps of C4, and welded them in. Clutch MC mount is now stiff enough to earn the vaunted "wedding dick" rating from my Dad (RIP).
Got about halfway through welding up the clutch pedal and ran out of wire. There's now about 2.5 lbs of wire in this car.
Hot as balls out there today. Sweet sweet relief: watermelon sticks from the fridge.
with the pedal box pretty much done, i moved on to the steering system. to keep the vintage appearance and feel from the driver's seat, i chose to keep the Corvair steering column intact. now, back in the day, this car was built with a one-piece steering shaft, from the steering box mounted ahead of the front axle, up to the steering wheel and, sometimes, through the driver's chest. to join this with the C4 rack, I have to cut the 5/8" diameter steel shaft, support the free lower end of the shaft with some kind of bearing / bushing, get the shaft pointing in the right direction, and connect it to the C4 rack. Step 1 was easy, just mark and cut about 2" beyond the end of column jacket. Step 2 was also pretty easy, because I received a box full of actual good stuff in the GRM New Years Game last year. I dug out this 3/4" ID flanged spherical bearing, and liberated it from the flange:
the OD of the race was slightly larger than the column jacket, so I cleaned up the jacket and tacked the race right to it:
the 5/8" shaft is loose inside the 3/4" bearing, and this is where i hit my budget for $4.52 plus tax at Lowe's High Performance Chassis Parts, for a 3/4 x 5/8 bronze bushing. slipped it over the shaft and secured it with a hose clamp:
to get it pointed in the right direction is another budget hit. from Sweet Mfg I picked up this single u-joint that takes a 5/8" round on one end and 3/4" DD on the other:
at about $70, its probably the single largest cash outlay after the C4 and the Corvair. to connect it to the C4 rack, I need to shorten the C4 i-shaft to 5-1/2", and I have to machine the raw 0.820" OD down to the 3/4" DD shape. no sweat. first, sawzall removes the upper yoke.
then i chuck the cut end in the lathe and support the other end with a dead center. mark where the 3/4" diameter will begin, find a cutter ground with a radius to avoid stress concentrations, and turn the shaft down to 0.750". Mark for location of flats:
and that's where i left off last night. today i spent lunchtime in front of the vertical mill at work, machining the flats that make a 3/4" round into a 3/4 DD. finished product:
now, here's the only part i don't really like. the upper end of the u-joint gets welded to the Corvair upper steering shaft. i prefer things that can be non-destructively disassembled, but i'll get over it. i think i'll have to loosen the column jacket from the dash for assembly / disassembly, but that's OK, at least i know it and have planned for it. so by the end of the night tonight i'll be able to steer my C4 rack with my Corvair wheel, and that's another big milestone.
Can't you through bolt the ujoint to the upper shaft?
I was concerned about the clutch slave bracket a couple days ago but figured you probably had a plan based on your profession. Glad to see the reinforcement brackets.
preach said:Can't you through bolt the ujoint to the upper shaft?
Thats what i did in the duster. A roll pin would also be an acceptable answer
Dusterbd13-michael (Forum Supporter) said:
preach said:Can't you through bolt the ujoint to the upper shaft?
Thats what i did in the duster. A roll pin would also be an acceptable answer
That’s what I said too. He told me his shaft doesn’t have enough girth
wawazat said:preach said:Can't you through bolt the ujoint to the upper shaft?
Thats what i did in the duster. A roll pin would also be an acceptable answer
That’s what I said too. He told me his shaft doesn’t have enough girth
Thats actually more than I needed to hear!
I think a hardened 3/16 rool pin would do the job; maybe tacked in place?
03Panther said:wawazat said:preach said:Can't you through bolt the ujoint to the upper shaft?
Thats what i did in the duster. A roll pin would also be an acceptable answer
That’s what I said too. He told me his shaft doesn’t have enough girth
Thats actually more than I needed to hear!
In reply to all of the above, I did not want to drill through the 5/8" diameter upper shaft, so I welded it. And it came out pretty decent. I can still disassemble everything except the u-joint from the upper shaft, but I don't expect to have any issues with either.
I like it.
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