This is from an 05 LS2 GTO service manual but the LS2 and LS7 cover use the same adjusting procedure.

 

Hey guys, as I was reading this post it was about to make me scream really loud and cry at the same time ..Some of you who are making statements about certain things dont have a clue about whats going on, so you should just this thread...I will try an not be a salesman but yet be a very helpful person who owns a shop thats a full service shop, who has installed and sold thousands of clutches in LS series cars over 14 years...

Rules to always follow when installing any clutch...
1st.. Make sure and know what you are buying will work perfectly on your car, without any custom work...Speak with someone who knows what the hell there doing...

2nd..When doing a clutch replacement on any LS series car, always replace the following items..(Flyhweel, Disc, Pressure Plate, Pilot Bearing, Throw-out Bearing, Slave & most of the time a Clutch Master too)...If these items are not replaced all at the same time you will take the chance of having disengagement & engagement issue's...which can reduce the life of your new clutch alot...

3rd..Ask who ever you are buy the clutch items from if you will need a shim behind the slave...They should know if that clutch does not have the same installed height as the Factory OEM clutch for that car...But I can definitely tell you guys this, for the 3-4 weeks that we have been on THIS forum, alot of end users and businesses dont know or even have a clue what they are talking about...

4th..Taking measurements is always a good thing to do ...The Installed Height from the back of the engine is most important...Next is to torque the bolts in the proper bolt pattern, torque spec's & sequence...once everything is installed, now comes the bleeding of the system...Its much easier to purchase a remote clutch speed bleeder kit so you dont take the chance of getting clutch fluid on your new clutch inside of the bellhousing...plus its alot easier to bleed the first time and everytime after...You need to always make sure and get all the air out of the system...NEVER pump the pedal really fast it will cause air bubbles to get inside of the fluid...

5th..Once done with the bleeding process get into the car and push the clutch pedal slowly to the floor a few times...Crank the car while in the air or on a flat surface, try very slowly to but it in first gear with the pedal all the way down...let the pedal up very slowly, the car should not start to move until the pedal is at least a couple of inches off the floor, if it does start to move before then, there is still air in the systems...So go back and bleed it somemore...If its being a real bitty then make sure its full of fluid and loosen the res. cap a little and leave it alone over night, air thats trap most of the time will always rise to the top...DO NOT DRIVE THE CAR IF THERE's AIR IN THE SYSTEM..!!

Just and FYI...we all know that the Clutch Masters in the F-bodys are junk from the factory...

00firehawk: you should not have to use a shim with an LS7 clutch at all...especially if you replaced all of the above that I mention...The LS7 Clutch will work in any F-Body or C5 corvette without shims or any issue's, we have done hundreds of them without...LS7 CLUTCH IS NOT JUST MENT TO BE USED WITH AN LS7 Slave...If someone says this please dont listen to them...You can use a C5, F-body or GTO slave with an LS7 Clutch...

Mike454SS: You have been pretty much right on perfect with everything you have said...

And no offense, to another clutch seller involved in this discussion, but his $369 clutch does not come with a NEW Flywheel, our LS7 Clutch kits that we sell DO come with a NEW Flywheel for only about $70 more...IMO, I would definitely spend $70 on a New Flywheel rather than use my 9-11 year old flywheel with xxx,xxx miles on it & with having to resurfacing it, No way, not at my shop and us having to warranty it...

Please, If any of you dont know why an LS7 Slave is longer, please dont listen to anyone in this thread so far...

The LS7 Slave is taller because the mounting area on a C6 is almost a full 1" back further than an F-body, GTO or C5 corvette...Which also means the C6 bellhousing is almost an 1" deeper than the others...


raven154: Thanks for the pic's...

And further more, I'll put my 28 years of experience up against anyone...

I'm not the greatest typer, but if anyone of you would like to call me anytime I will be glad to explain in english, all about everything you have read here...

 

^^^He's right about the LS7 slave length being almost an inch longer for the reason he stated. I would have mentioned it but I thought that was understood at this point lol I have never installed a clutch in an F-body so I can't tell you that you need a shim or not. Only advise I can give is measure three times, install once. Personally, I have trust issues with this kind of thing. Its easy to measure and it only ensures a quality installation so why not do it yourself instead of trusting someone else? Thats how I roll! lol

 

I agree with "most" of this. Its good information. I don't agree with the about not using a shim with an LS7 clutch, of course. Most LS7s seem to have a low pedal. The shim brings it back up, simple as that.
Why even bother with a stock adjustable pressure plate? It's just stock BS that GM uses. Notice that there are no adjustable pressure plates on aftermarket clutches. This is because they are not necessary, and it leaves room for error.
You are also correct about a lot of shops/people don't know what they are talking about. There are way too many know-it-alls.
As a matter of fact, I'm going to clear ALL of these disputes up. I'm in the process of designing/building a clutch testing fixture. This tool will measure pressure plate throw, engagement point, and pressure. It will be a good tool to truly compare different clutches. It's going to take several months to get it all done, but everyone here will be the first to hear about it.

 

Yes, you are absolutely right, the $369 clutch that I sell doesn't come with a flywheel. For that price, what do you expect? For another $275, I can include a new billet flywheel, which I recommend. However, this clutch kit will work just fine with a resurfaced stock flywheel. It doesn't matter if its 9-11 years old. Once its machined, the surface is just as good as new. I offer a one year warranty, and guess what? I haven't had a single one come back to haunt me. There is nothing wrong with resurfacing a stock flywheel. The only case which a stock flywheel shouldn't be used is with a ceramic disc which generates much more heat. The aftermarket billet flywheels are made specifically to handle the additional heat. Hence the high grades of steel used on the various billet flywheels.
I simply offer my clutch kits in several different packages to suit my customer's needs & budgets. I'm not going to try and sell something that isn't necessary. Salesmanship is not one of my strong points
Everything that I posted is based on my experience, which I have more than enough of. I don't have anything to prove to anyone, so this is all that I really have to say in this thread. Plus, I'm not big about getting into pissing contests.

 

My pendal is at the top. Has been for over 40,000 miles with no shim. It speed shift super easy and never grinds. On my ls7. Im going tdp next. I plan to go to the track now that i have a 9". Ive been 1.68 60" and 11.3@120mph on ten bolt and ls7.

 

great thread. now how do i proporly measure the height on my clutch setup? i own a press should i reset the ls7 clutch pressure plate?

 

EastcoastPerformance...THANK YOU.

The reason I mentioned that one specific guy shouldn't measure...is I don't think most people are capable enough of an accurate enough measurement (tape measures and straight edges don't cut it)...I am ALL FOR measuring WHEN you have the proper measurement tools, and the ability to use them properly...but when 9 out of 10 machinists I meet don't know how to use a micrometer (and I meet new machinists every day in my line of work), I lose faith in the general public knowing how to measure anything more accurately than a carpenters tape measure...the general shadetree mechanic who's saying "should I put a shim in here?" without initially thinking instead to ask "whats the height of the fingers of the LS7 pressure plate off the bellhousing flange when installed with all LS7 parts as compared to all LS1 or LS6 parts?" instead...no offense to any of them...but I don't think you would know how to make an accurate measurement.

And for what it's worth...if you make friends with someone behind a parts counter at a dealer...the LS7 clutch/flywheel combo is DAM cost effective...plus mine drives LIKE STOCK...in traffic...I can't tell it's there at all...but when I sidestep the pedal...it certainly does snap harder than the LS1 clutch did well over 100K miles ago.

 

When the slave is brand new, uninstalled...fresh out of the GM box...it's fully extended to a stop...I haven't tried to pull one further, but if I'm remembering it correctly, if you over extend it, it will bind up against that stop, and possibly break...I agree with you it will also risk pressure plate damage, but I still maintain that I'm not wrong about overextending it. Hydraulic pressure can be an incredibly strong thing...especially when you're pressing on it with your foot on a lever arm...

 

If you want an accurate measurement, assemble the clutch to the flywheel off of the engine, then lay it on a flat plate and take a measurement...trying to do it under a car is just not as easy.

I would not adjust the pressure plate UNLESS you find that measurement to be off...and if it is, THEN I would adjust it back until that height is correct...what that height should be, I do not off the top of my head know.

 

...and for what it's worth raven154...you have a CTS-V...which I'm pretty sure DOES have a longer bellhousing than an F-Body...so in your case, everything else being the same (hydraulics, clutch assembly), you would need a spacer, and your measurements should have told you just that.

 

I really don't understand this. If the pressure plate self adjusts for air in the hydraulics...it is self adjusting to require LESS throw from the slave cylinder to disengage the clutch...once you've removed all the air from the hydraulics, you've now got full throw from the slave cylinder...and possibly not parking far enough back...I'd see it manifest as problems re-engaging the clutch...sorta like riding the clutch pedal down all the time.

 

and everyone please understand, I am trying to keep my argument technical, I'm not trying to insult anyone, or bash anyone, or hurt anyone's sales as a sponsor...but the LS7 parts are GREAT parts for a street driven mild/bolt on's LS1 F-Body, and so long as they're not damaged (over adjusted incorrectly) prior to installation, you really can bolt them in, thoroughly bleed your new f-body hydraulics, and drive away with a smile on your face

 

I hope so. I just bought a slightly used one from a reputable member on this site and I hope it holds up. Im no mechanic so im having mine install it for me when I have the engine rebuilt. I will have all new parts/master,slave,minus the ls7 used clutch.

 

Today I ran across something really interesting which is going to help build the clutch testing fixture. I got ahold of the prototype C5 Vette bellhousing which came from GM's testing facility. It never was used in a production car, but its a really cool piece. Its basically a bellhousing with an internally mounted slave cylinder. For all I can tell they maybe just used it for testing purposes. I "borrowed" this from a friend who knows some people. I'm going to use it as a template to modify another C5 bellhousing that I have. This way I can mock up all the hydraulics, clutch, everything and actually see it in action. It will come in really helpful especially when I begin testing my new master cylinder. Maybe I'll post pics

 

Pics??? Sounds interesting!

 

Some of the information in this thread is ludicrous.

Self adjusting pressure plates are a bad idea? No, they are a function of a stock clutch for the purpose of long life. This isn't a performance aftermarket clutch afterall, it's a stock clutch that is designed to last 100,000 miles. Aftermarket companies don't use them because they don't have to meet the requirement for life that a GM stock clutch has to meet.

Also noted above, the LS7 clutch setup isn't meant for a longer slave cylinder. The longer slave cylinder is used because of it's mounting location being further back. Different slave cylinders for different applications, not different clutches for different slave sylinders. You should not have to use a slave spacer with an LS7 clutch. There are ALWAYS outlier results of course, especially when there are 100s of thousands of a particular clutch on the road, so I could see a handfull of people needing to space their slave slightly.

Be wary of any claim that someone has "seen the stock adjusters mess up more times than not." It's an obvious overstatement considering the HUGE number of these clutches on the road and we don't hear of such problems. Every C6 and Z06 after 2006 and 2010-11 Camaros come stock with this clutch. The huge number of people who swap them into F-bodies, GTOs, C5s, etc.

30-40% have engagement issues? Seriously? Someone isn't installing something correctly, end of story.

There's just too much exaggeration from one source for any of it to be credible, especially when so many people spread out all over the country have installed countless LS7 clutches without ever experiencing those issues. It is a solid stock-like replacement clutch that has a much lower problem rate than ANY aftermarket clutch, and that's with exponentially more of them in vehicles than any aftermarket LS clutch.

 

^^ And thats why I went with this clutch. The more I looked into the other clutches, the more inconsistencies I saw with people having problems. This is after all built for gms top of the line vehicles.

 

My stock clutch made it 210,291 miles (the last 13K had issues with the pedal staying on the floor when driving like an ***, and the last 150 were very very painful...but it got the car home to Worcester MA from the GW Bridge (it started slipping in 6th on the bridge, but I managed to limp the car home above the "minimum speed" on every highway...even though I had to use 3rd gear to get up the hills near U-Conn)...I certainly hope this LS7 clutch in my car lasts just as long too (yes I do intend to put 400-500K miles on this car...why not?).

Again, thank you as well, for posting something that MAKES SENSE and is logical.

Among the B-Body crowd, there was much to do years ago when swapping T56's into the cars...people hated to use the LT1 style hydraulics and clutches because they saw 1 fail, or one guys headers were too close to the slave and damaged it...and they insisted it had a high failure rate.

I had the same argument over there...THOUSANDS of LT1 M6 F-bodies were produced...and every single one of them, had that hydraulic setup in it...it's fine...and I always just ran completely stock LT1 hydraulics in my T56 converted Caprices...without any issues EVER...all the guys going to the "better" setups...were also posting probably every 8-10K miles about how they were rebuilding their aftermarket slave cylinder again, and trying to find a different source for a replacement throwout bearing...and I would always chime in and say something along the lines of "I'm up to 75K on my 'stock junk' now...haven't even thought about it since I took the car for the first drive"...

Here's to hoping the rest of the Camaro can hold up to mileage like the old clutch did, and like I hope the new clutch will...

 

well that is the reason why i went with the LS7 as well. i used a small spacer, while i might have screwed myself by using one, I haven't noticed any slippage, and have the pedal directly in the center of the throw. I recommend the clutch for anyone wanting a nice upgrade from the stock clutch and doesn't race their car on slicks.