I had posted this in the transmission forum a couple of days ago, but that area seems fairly dead, so I hope you don't mind if I ask the same question here.

I've had an inconsistent pedal feel on my B16A clutch for quite some time, especially when the car is driven for an extended period of time and gets hot. It goes from smooth to making screeching noises that can not only be heard, but felt. The car has been turbocharged, so heat from the turbo may play a role. Both the master and slave cylinder have been replaced, along with the short section of rubber hose by the firewall, which is now Teflon hose. Last year, I tried to inject more urea grease through the hole where the clutch fork is, but there's only so much you can do without removing the transmission.

The other day, I noticed that Clutch Masters sells an internal hydraulic clutch bearing, indented for use with their twin disc clutch kits. I spoke with someone at Clutch Masters and was told this would also work with single clutch kits, but I'd like to confirm this with a few more people. I tried searching online for review of this product on a Honda, but couldn't find anything. Before I consider this as an option the next time my transmission comes out, has anyone here used this and do you like it or recommend it? Thanks for the help.

N817- H (B-Series) - Clutch Masters

 

Turbocharger will have nothing to do with the transmission and any exigent heat emanating from it. So, scratch "Turbo" off the list of causes right now.

I will say I've used Clutchmasters for about everyone of my 6 personal projects I've used over the years. From 200whp to 650whp. Never once had I used anything other than the standard throwout clutch bearing used (that or Exedy).

Transmission fluid gets hotter than people think. Much hotter. (over 300*F) on average. This sounds more like either the transmission fluid you may be using, or the fact that depending upon your purpose of use, might be time for a trans-cooler, with better fluids.

I've only used either Honda OEM MTF, Kaaz Grade Level 5, or Gear X in any of my transmissions, as they all used OS Giken, or Kaaz Clutch-Type LSDs. (This is dependent upon purpose of use, of course.)

Not sure with which direction to point you. You can try the bearing, and use the same fluid and see what happens. If you change fluids at the same time, you'll have sandbagged your own test (is it fluid, or the new bearing that repaired this? ) Hard to say

 

Triple check that there is no air in the line or reservoir. Fading/changing feel in the pedal can often be attributed to even small pockets of air in the CMC/lines.

Semi-related but I've always used Amsoil Synchromesh for transmissions and differentials. Great results.

 

Thanks for the replies, I appreciate it. I just want to say that the car shifts beautifully, and the only problems I've experience have been when sitting at a stop light going into first or getting into reverse. I had used Amsoil Synchromesh for over a decade and recently switched to Synchrotech's Torco MTF fluid. I did notice a difference with this, and not because the fluid was new. The Amsoil in my transmission was also new, but as I mentioned, I never had problems shifting the car when driving, only when I'm at a stop.

I can't figure out the inconsistency, though. It's really strange. I don't know how much urea grease was used, if any at all. I'm wondering if the heat breaks down the small amount that's in there and creates this screeching noise I explained. The turbo does significantly raise under hood temperatures, so I don't know why that wouldn't play a role. The only extra thing I might add is that I used to have an ACT XTSS clutch, then eventually the same pressure plate with a Competition 6 puck, which had a pedal pressure so high that it broke the clutch fork in the transmission, the clutch pedal itself, along with the master and slave, though not necessarily in that order or at the same time. (I forget the chain of events, as it was a long time ago.) I think what I may do the next time the transmission is out is to replace the clutch fork and pivot ball or any other parts that may be worn. Even after adding fresh hydraulic fluid and bleeding the system, the noise was still there. I also replaced the hard line from the slave to what was previously a flexible factory rubber hose.

Shodan, I think we had this discussion before or possibly I've read through one of your old posts about Clutch Masters. I'm still on a Clutchnet Kevlar clutch and I love the thing, but when the time comes, I may use Clutch Masters. The person I spoke with on the phone steered me away from the FX300 Kevlar at my current 320 ft/lb torque level (Possibly going up after my E85 tune.), and thought I should be using a FX400 6 puck (Not available in 8 puck, unfortunately.) Your old post mentions their 6 pucks being Kevlar, but I see that they're ceramic now, which I'm not crazy about in a daily driver. I don't know what power level your ITR is now, but are you using a 6 puck ceramic or Kevlar? I think a lot of times, people recommend an overly aggressive clutch without taking into account the person's driving habits. It's my daily driver, I don't drag race, and hitting the rev limiter is a rarity. I mentioned this to Clutch Masters, but he still thought 6 puck was the way to go.

 

I realize you're asking Shodan, but I daily drove a 400WHP S2000 on a "stage 4" 6 puck sprung Clutch Masters ceramic clutch (with the accompanying pressure plate). Put about 20K on that clutch before the car was sold.

The pedal feel was stiffer than stock, but definitely not what I would define as heavy. By no means was it a leg workout. The engagement was right around the middle of the pedal. It was a relatively "grabby" clutch, but I VERY RARELY ever stalled it out, minus a couple times the first week getting used to it, and you could definitely still slip the clutch in traffic and drive the car pretty smoothly.

Of course all of this is relative to each person, but I'll put it this way: I currently live in Austin, TX. We have high traffic congestion, and a lot of steep hilly areas. While the CC Stage 4 probably wouldn't be my first choice, if I had to daily that clutch here I don't think I'd have a problem living with it.

As for your clutch noise, at this point it sounds like you'll just need to eventually pull the trans off and inspect things for yourself. I'd check the wear on the pressure plate and throw out bearing to start with.

Edit: To add, the clutch was sprung.

 

Underhood temperatures just don't transfer to the transmission case. We have so many NA applications that need trans coolers for these cars that get hot from transmissions getting so hot. The two really are unrelated. If the trans were to get that hot, from just exigent heat, the bay would have caught on fire many moons ago.

I'm using the ceramic 6 puck SPRUNG disc ( there's no need for 8. Makes no sense.)

Currently I'm over 375lbs-ft of torque using this clutch on the Integra and it's very easy to drive with.

 

I could drive a 6 puck, but going in reverse, for example, was annoying. Kevlar is like butter.

All I can tell you is what I've experienced. I'm not saying the transmission itself is getting too much heat transfer, but considering the slave cylinder is in close proximity to the turbo, I still think that's a possibility. When the car gets hot in traffic, this is when the problem occurs. This is why I had thought of eliminating that, by going with the hydraulic CM bearing. I keep replacing parts and the problem still exists.

I mentioned an 8 puck, because they have smoother engagement. Clutch Masters said they're not available for my car, though.

 

I understand. Hopefully I can put your mind at ease with your theory by telling you based upon my experience from enduro racing and turbocharging together, this is an area that is not a significant factor.

 

My 3 puck exedy stage 2 is very easy to drive, I think it depends on the overall clutch design and manufacturer more so then just how many "pucks" it has

 

How much surface contact the clutch has, what material the clutch is made out of, if springs are present in the clutch plate, and what pressure plate is being used with the setup.

Hell, even the throw out bearing, slave, master, lines, and fluid can all have minor impacts on clutch feel.