Das Projekt Nein Fo-Fo

[Huckleberry]

I decided to take her out for a spin last night on some twisty back roads, and the car is an absolute riot to rip around the curves. Considering that I used junkyard Koni struts because they had the 200lb NLA Weltmeister springs I wanted and the Koni shocks that came with the car, and I know I added weight to the nose of the car with the iron block and hydroboost, she felt very balanced and controlled. Having her rip around a curve screaming at 6000 RPMs is definitely a hoot.

Unfortunately, the fun was cut short when the hydraulic release bearing decided to puke fluid all over the ground. No clutch. No go. I called Grundy to get a tow, and much to my surprise, they told me they can't schedule a tow after hours.

Luckily, my friend was able to come and flat-towed me home. Now I just need to get things apart and see what the hell happened.

Dang.
From to
I'm sure you'll get it sorted out pronto and will be beating on it again soon.

In4pics on the road.

Yeah, it went from "fun" to "not fun" in short order. It sucks for many reasons, but a big one is that I was just approved for a royalty entry into Philly Radwood, which now I'm probably going to miss.

[wap]

Dang.
From to
I'm sure you'll get it sorted out pronto and will be beating on it again soon.

In4pics on the road.

Yeah, it went from "fun" to "not fun" in short order. It sucks for many reasons, but a big one is that I was just approved for a royalty entry into Philly Radwood, which now I'm probably going to miss.

Sorry, mang. When it the event?

[Huckleberry]

Yeah, it went from "fun" to "not fun" in short order. It sucks for many reasons, but a big one is that I was just approved for a royalty entry into Philly Radwood, which now I'm probably going to miss.

Sorry, mang. When it the event?

June 10th.

I'm going to see what their cancellation policy is.

[golftdibrad1]

I decided to take her out for a spin last night on some twisty back roads, and the car is an absolute riot to rip around the curves. Considering that I used junkyard Koni struts because they had the 200lb NLA Weltmeister springs I wanted and the Koni shocks that came with the car, and I know I added weight to the nose of the car with the iron block and hydroboost, she felt very balanced and controlled. Having her rip around a curve screaming at 6000 RPMs is definitely a hoot.

Unfortunately, the fun was cut short when the hydraulic release bearing decided to puke fluid all over the ground. No clutch. No go. I called Grundy to get a tow, and much to my surprise, they told me they can't schedule a tow after hours.

Luckily, my friend was able to come and flat-towed me home. Now I just need to get things apart and see what the hell happened.

What size MC and SC are you running? do you think the bigger MC could have caused the seal to blow on the SC? The other thing to check might be for bottoming, ie if the stroke of the slave/master combos are all good, maybe the clutch pack is bottoming causing your fluid pressure to spike? This won't do favors to your thrust bearings either.

Curious to hear what you find.

[Huckleberry]

I decided to take her out for a spin last night on some twisty back roads, and the car is an absolute riot to rip around the curves. Considering that I used junkyard Koni struts because they had the 200lb NLA Weltmeister springs I wanted and the Koni shocks that came with the car, and I know I added weight to the nose of the car with the iron block and hydroboost, she felt very balanced and controlled. Having her rip around a curve screaming at 6000 RPMs is definitely a hoot.

Unfortunately, the fun was cut short when the hydraulic release bearing decided to puke fluid all over the ground. No clutch. No go. I called Grundy to get a tow, and much to my surprise, they told me they can't schedule a tow after hours.

Luckily, my friend was able to come and flat-towed me home. Now I just need to get things apart and see what the hell happened.

What size MC and SC are you running? do you think the bigger MC could have caused the seal to blow on the SC? The other thing to check might be for bottoming, ie if the stroke of the slave/master combos are all good, maybe the clutch pack is bottoming causing your fluid pressure to spike? This won't do favors to your thrust bearings either.

Curious to hear what you find.

The slave is a Tilton 8100 hydraulic bearing. Their website lists the piston area at 1.215 sq.in. The master is a 1" bore Wilwood with a 1.100" stroke. The 1" bore is the only way I could get the clutch to release, and it still took almost the full pedal travel to get it done. I think I just had the piston right on the edge of the seal and the high RPM shift was enough to dislodge it. I looked in the bellhousing last night and the piston is stuck out with the seal folded over. I'm hoping the release bearing itself isn't damaged and I can just get a new seal kit, but I won't know until I start pulling things apart.

I was in the middle of the .100" - .150" bearing clearance (.133", if I recall), so I'm going to have another spacer made that puts me right at the minimum .100" clearance. I may also need to brace the firewall, as I think flex may be stealing some of the effective stroke of the pedal. Hopefully, those two things will get my clutch working a bit better.

[golftdibrad1]

What size MC and SC are you running? do you think the bigger MC could have caused the seal to blow on the SC? The other thing to check might be for bottoming, ie if the stroke of the slave/master combos are all good, maybe the clutch pack is bottoming causing your fluid pressure to spike? This won't do favors to your thrust bearings either.

Curious to hear what you find.

The slave is a Tilton 8100 hydraulic bearing. Their website lists the piston area at 1.215 sq.in. The master is a 1" bore Wilwood with a 1.100" stroke. The 1" bore is the only way I could get the clutch to release, and it still took almost the full pedal travel to get it done. I think I just had the piston right on the edge of the seal and the high RPM shift was enough to dislodge it. I looked in the bellhousing last night and the piston is stuck out with the seal folded over. I'm hoping the release bearing itself isn't damaged and I can just get a new seal kit, but I won't know until I start pulling things apart.

I was in the middle of the .100" - .150" bearing clearance (.133", if I recall), so I'm going to have another spacer made that puts me right at the minimum .100" clearance. I may also need to brace the firewall, as I think flex may be stealing some of the effective stroke of the pedal. Hopefully, those two things will get my clutch working a bit better.

This?
https://tiltonracing.com/product/8100-s ... e-bearing/

If so, Tilton is listing this bearing as a 0.70" maximum stroke.

The 1" bore of your MC has an area of 0.78in^2. 0.785 * 1.1= 0.8635 in^3 volume displaced

On the slave, 0.8635in^3 / 1.215in^2 area = 0.710 in displacement. Sorry to say my dude but i think you overstroked the MC/SC combo.

https://www.wilwood.com/PDF/Flyers/fl162.pdf
Reading up with your disengagement woes... I think you maybe still had air in the system. Continuing to up the MC size just made compressing it easier to enact the force you needed to the SC. The air may have worked out some (big vibrating car) and then you could fully stroke that slave....then the oopsie.

In that same thought...a SMALLER MC should REDUCE pedal effort while INCREASING stroke to do the same work/travel on a given SC. Referring to the chart by our good buds at wildwood notice how for a given pedal ratio (column) pad force INCREASES for a SMALLER MC. This is just like how a jack works, small piston with big stroke / makes big piston move little with big force.

I'd look at what it would take to be closer to the minimum side of the spacer spec and drop the MC a size or two. That should help reduce your firewall flex to via lower force inputs.

Final thought as you resolve all this: Pedal stops on custom builds are vastly overlooked and necessary for the throttle and clutch. Us humans can produce incredible amounts of force with our legs, and when multiplied through adrenaline and levers things WILL break. I had to add these on the kit cars. I suspect once you resolve your MC/SC clutch issues you can rig something easy enough, but make sure to look at the throttle too. You can bend all manner of expensive shit on the throttle, linkage, pedal itself, snap cables, etc, etc.

Good luck.

[Huckleberry]

The slave is a Tilton 8100 hydraulic bearing. Their website lists the piston area at 1.215 sq.in. The master is a 1" bore Wilwood with a 1.100" stroke. The 1" bore is the only way I could get the clutch to release, and it still took almost the full pedal travel to get it done. I think I just had the piston right on the edge of the seal and the high RPM shift was enough to dislodge it. I looked in the bellhousing last night and the piston is stuck out with the seal folded over. I'm hoping the release bearing itself isn't damaged and I can just get a new seal kit, but I won't know until I start pulling things apart.

I was in the middle of the .100" - .150" bearing clearance (.133", if I recall), so I'm going to have another spacer made that puts me right at the minimum .100" clearance. I may also need to brace the firewall, as I think flex may be stealing some of the effective stroke of the pedal. Hopefully, those two things will get my clutch working a bit better.

This?
https://tiltonracing.com/product/8100-s ... e-bearing/

If so, Tilton is listing this bearing as a 0.70" maximum stroke.

The 1" bore of your MC has an area of 0.78in^2. 0.785 * 1.1= 0.8635 in^3 volume displaced

On the slave, 0.8635in^3 / 1.215in^2 area = 0.710 in displacement. Sorry to say my dude but i think you overstroked the MC/SC combo.

https://www.wilwood.com/PDF/Flyers/fl162.pdf
Reading up with your disengagement woes... I think you maybe still had air in the system. Continuing to up the MC size just made compressing it easier to enact the force you needed to the SC. The air may have worked out some (big vibrating car) and then you could fully stroke that slave....then the oopsie.

In that same thought...a SMALLER MC should REDUCE pedal effort while INCREASING stroke to do the same work/travel on a given SC. Referring to the chart by our good buds at wildwood notice how for a given pedal ratio (column) pad force INCREASES for a SMALLER MC. This is just like how a jack works, small piston with big stroke / makes big piston move little with big force.

I'd look at what it would take to be closer to the minimum side of the spacer spec and drop the MC a size or two. That should help reduce your firewall flex to via lower force inputs.

Final thought as you resolve all this: Pedal stops on custom builds are vastly overlooked and necessary for the throttle and clutch. Us humans can produce incredible amounts of force with our legs, and when multiplied through adrenaline and levers things WILL break. I had to add these on the kit cars. I suspect once you resolve your MC/SC clutch issues you can rig something easy enough, but make sure to look at the throttle too. You can bend all manner of expensive shit on the throttle, linkage, pedal itself, snap cables, etc, etc.

Good luck.

Yeah, I knew I was on the cusp of the bearing's travel. I actually have a pedal stop installed, but even with it ran all the way in, getting into first and reverse was challenging. So, I made a lower profile pad to thread in to try and find that sweet spot. I guess I went too far and what tested out fine in the garage proved to not be fine after things heated up. I think getting the bearing shimmed to its minimum clearance, which will bring it about .030" closer to the clutch fingers, will do the trick with the pedal stop in place.