BadAss SRT-Z - 2.4L / A568 - Update!!!

[blk86trbo]

Will call to put insurance on it tomorrow!

I also just called my insurance agent and swapped a bunch of cars around on the policy lol

Way to go on the Z, that shield looks really nifty!

[BadAssPerformance]

whats the break in procedure for the act clutch?

Good question. Most "race" type clutches don't get street driven, so probably once around the block will be fine, LOL

[turbovanman²]

Very cool,

[Reeves]

I'd give the clutch hell after a trip around the block. IF it ain't gonna hold, it ain't gonna hold. I never was a fan of the break in stuff.

[Shadow]

Damn, no wonder you guys have so much trouble with clutches/ trannies! lol A clutch needs "seat" time in order to insure that the Whole contact patch is "seated" to the flywheel/ PP surfaces. If only 50% of your clutch material is seated, you will no doubt slip the clutch the first time out, even though it was a clutch that would hold ALL your power if broken in properly.

Now on the other hand, IF you happen to have a disc and flywheel/ PP surfaces that are a near perfect match right from the get-go (ie. no high or low spots (we're talking 0.005" or less here) then you may have no problems.

I for one Always play it safe and materials like ceramic are way more important to break in properly than organic. If your familiar with breaking in a clutch, you will actually Feel when the breakin is done. Engagement will suddenly get smoother, less grabby as the whole surface is now contacting evenly instead of only catching the highs

[Reeves]

Damn, no wonder you guys have so much trouble with clutches/ trannies! lol A clutch needs "seat" time in order to insure that the Whole contact patch is "seated" to the flywheel/ PP surfaces. If only 50% of your clutch material is seated, you will no doubt slip the clutch the first time out, even though it was a clutch that would hold ALL your power if broken in properly.

Now on the other hand, IF you happen to have a disc and flywheel/ PP surfaces that are a near perfect match right from the get-go (ie. no high or low spots (we're talking 0.005" or less here) then you may have no problems.

I for one Always play it safe and materials like ceramic are way more important to break in properly than organic. If your familiar with breaking in a clutch, you will actually Feel when the breakin is done. Engagement will suddenly get smoother, less grabby as the whole surface is now contacting evenly instead of only catching the highs

So how does JO SCHMO racer do it? You know....all the 5 or 6 speed guys with NO WAY to drive it on the street?

[Ondonti]

So how does JO SCHMO racer do it? You know....all the 5 or 6 speed guys with NO WAY to drive it on the street?

They don't. Thats real life. They never do. What you said above is all there is. If it holds it holds. Less material touching isn't really going to make it slip or a full face would hold better then a 3 puck. Breaking in might help with street manners but who replaces enough race clutches to compare 1000 mile breakins with no breakin? Nobody.

[22shelby]

ill make sure to get JT's "break in period" on film... you know after the trip around the block

[BadAssPerformance]

Years ago I had a few great discussions with Rob Smith, the owner of RPS Turboclutch and multi-patent-holder, patents many other clutch companies have copied... and his clutches were one of the pioneers in FWD drag racing. He knows his stuff. The clutches came with instructiosn that basically said to break it in, drive it semi aggressively and it will seat quick, long break in not needed. Now, of course these were instructiosn for RPS clutches, not other manufacturers, but the full organic disks and ceramic puck clutches came with the same instructions

Think about it, if the surfaces are a couple thou off, they will plane themselves off either way... its the repetatve engagements that let them "bed"... so if 500 miles on open road doesn't really help as much as a bunch of engagements... the same amound could be had in less than 50 miles in town.

I think Rob's point about "material" and the "amount on variation" are accurate as you dont want to melt/compromise the material before it breaks in, however if the variation is tiny, break in needed will be minimal. I have never measured the surface variation on a disk, but think .005" would be a ton

Brent's theory on less area would actually hold better (like a 3-puck) is interesting...

Not sure it works that way tho as the smaller puck area has to deal with more friction/heat. Rob Smith had also told me a neat story of a 1200 WHP turbo Viper that had his highest HP rated puck clutch in it... in a couple long pulls on the dyno it was slipping. They swapped in a full face organic with the same plate and teh next day it held up for the whole day. Something to be said for more material to dissipate heat/energy

---------- Post added at 08:07 PM ---------- Previous post was at 08:06 PM ----------

ill make sure to get JT's "break in period" on film... you know after the trip around the block

Sweet! As of tomorrow it will be insured... got a few things to button up on it before the track tho

[Shadow]

Better street manners and longer disk life is what I've personaly noticed. I've seen those who have gone out and balls to the wall right away and usually a 4 puck will last a summer, maybe 2 (5-10000kms). Then I've seen a 4 puck that was broken in over a long period (800 kms/ 500miles) with 20000kms on it that still looked almost new. (both were identicle clutch and hardware ordered at the same time and put into these two cars within weeks of each other)

The 4 puck that I originally ran in the Charger was down about 50% after several hundred 1/4 mile passes and at least 20000 street kms and I think I did most of the wear on the last week end of racing when I was slipping it every other pass and then launched in 2nd gear slipping it all the way through.

But yea, I hear what your saying James and all I can say is a clutch can be broken in quickly, but it seems to eat the disc faster and even gouge the flywheel PP worse, so I guess you just end up going through more parts.

I have also heard of big $ racers who will have the disc material re-machined and balanced to a higher tolerance for better and faster seating, this is where you get into really high $ clutches also, they prob need less break in because they are machined and balanced to a higher quality and spec.

Guys, I hope you realized I was joking about my comment, and by the lack of flaming I'm guessing you did! (good stuff, maybe a first! )

I just didn't want someone who has a street driver and could otherwise do a proper break in to read this and think there was no benefit to it.

Only other thing I can add (and who knows, maybe it's all in my head) is that it's interesting that 500 miles/ 800kms is the chosen length of break in for most clutches. Like I said earlier, it's alway right around that time when I suddenly notice (specially on a puck clutch) that my rpm to leave the line smoothly drops 5-800 rpm, even my 3 puck did this. I've also driven cars that were not broken in with puck clutches and the severe "chatter" and rough engagement never goes away, it's there for the life of the disc.

[Ondonti]

3000gt's do not have a flat surface on the flywheel and not everyone grinds them correctly. Pretty sure ours are quite boring.

I would definitely say that ceramic does not like heat. If it slips hard and melts it turns into some sort of hardened garbage that will never work again. Organic will slip a little and not lose its effectiveness. I don't think that Viper's story is complete. If it was slipping in the first place then the combo was not adequate. Ceramic just self destructed as it always does. I would bet somebody already hurt that clutch before it went on the dyno. Seen someone else's clutch puke out black dust on the dyno when boost hit only to find out that it was already garbage when he got there and not something to brag about. People seem to think their clutch will hold on the dyno when its slipping on the street. Who here has ever had a ceramic clutch that slipped from overpowering ever behave the same again? I remember one clutch I had where it held fine until that moment it slipped and it couldn't hold any sort of load after that.
Other materials also seem to grab harder when hot, just not cerametallic. I still want carbon.

For me the worst thing for engagement has been aluminum flywheels made by fidanza. .

[BadAssPerformance]

Guys, I hope you realized I was joking about my comment,

Yep

I would definitely say that ceramic does not like heat. If it slips hard and melts it turns into some sort of hardened garbage that will never work again. Organic will slip a little and not lose its effectiveness. I don't think that Viper's story is complete. If it was slipping in the first place then the combo was not adequate.

For me the worst thing for engagement has been aluminum flywheels made by fidanza. .

Years ago, Tommy had a Fidanza in his charger for a couple passes and didn't like it so swapped in a stocker at the track LOL

The Viper story is as complete as it was told to me... I was told it when I was asking about switching from full face organic to a puck clutch. The puck has the theoretical less area / higher force, but also less material to dissipate heat, so maybe it just couldnt take the heat? or was under rated? Or not broken in properly, who knows...

Another observation... The clutch in my T2 Shadow right now was a one off "more than 40% over stock plate with 4-puck" prototype from Clutchnet. Started in the Z in 2004 (2.2L) around the block break in, by the 5th and 6th passes it was slipping.. took it out and put the second ACT 2.2L prototype went in (the first was in the Shadow) The Clutchnet proto disk looked OK but the flywheel and plate were chewed up a tad. It went into the Shadow (think i did cut the flywheel, cant remember) and has been in there ever since with tons of 5k+ RMP launches on slicks, average 1.84 60'. Last time I inspected it the disk looked fine, the flywheel and plate were grooved. This has been the common thing I have found with th epuck clutches regardless of break in proceedure.

[black86glhs]

It's Story time here at T-M.

[turbovanman²]

Shadow makes sense, its like new brake pads, with either new or used rotors, it takes a few cycles to get the heat into the pad and to transfer material to the rotor so they bite and work better, like piston rings,

[BadAssPerformance]

It's Story time here at T-M.

LOL... here's a clutch story... friend (CobraT93) and I went to Winners Circle (local speed shop) for something and took 87 CSX #252 (bone stock except CSX Stage II LM) and on the way back, the clutch failed, while driving at a steady 45mph... WTF!? So it would not engage or disengage, pedal did nothing. open road ended and came to a stoplight, shut it off. Light turns green, put it in 1st, started it with the starter, clutchless shifted 2, 3, 4... worked great. Did this throu a few more intersections, and just when we thought we were gonna make it back to his place, again, steady 45mph, it just gave up and had nothing... OK, just coasted to a spot to pull off, I had AAA so call a tow. Called AAA up, they're like where ya at? I looked up an the sign said "Denmark II Adult Book Store" LOL! For soem reason the tow truck driver knew exactly where it was at and was there quicker than any other tow I've called AAA for

---------- Post added at 06:29 PM ---------- Previous post was at 06:26 PM ----------

Shadow makes sense, its like new brake pads, with either new or used rotors, it takes a few cycles to get the heat into the pad and to transfer material to the rotor so they bite and work better, like piston rings,

Transfer material to the rotor?

[Reaper1]

Yes. Brake pads transfer material to the rotor. This is partially how you get a higher coefficient of friction.

[BadAssPerformance]

On the molecular level tho, right? The ACT plate that came out of the car had visuble clutch pad chunks on it... I've never seen that before

[black86glhs]

Really bad pad transfer is similar to what your clutch looked like JT. You don't notice it like on a rotor. You "might" notice the clutch chatters or slips but it obviously isn't going to be like the brakes. Especially since the brakes have the fluid/mechanical connection that the clutch doesn't.

[BadAssPerformance]

I think the material transfer to the rotor is the part that is confusing... if the material were transfered, and retained, then rotors and flywheels would never exhibit wear, in fact they would get thicker... so to wrap my mind around this, I'm guessing this it the typical situation? .... The pad(clutch) material is transfered to the rotor(flywheel/plate) when braking(engaging the clutch) however in an ideal situation, only a minute amount of material is actually retained and most of the transfered material is disipated as brake(clutch) dust...

[black86glhs]

I think the material transfer to the rotor is the part that is confusing... if the material were transfered, and retained, then rotors and flywheels would never exhibit wear, in fact they would get thicker... so to wrap my mind around this, I'm guessing this it the typical situation? .... The pad(clutch) material is transfered to the rotor(flywheel/plate) when braking(engaging the clutch) however in an ideal situation, only a minute amount of material is actually retained and most of the transfered material is disipated as brake(clutch) dust...

Yes, only a very thin layer is transfered. You couldn't measure it without expensive tools....lol.