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2012 Boss stock clutch and trans shifting high rpms verse aftermarket

Ok playing around I was not trying hard just goofing off the car shifting at high rpms seeme to not want to shift it comes out of gear fine just as if there is a lockout keeping you from going back into gear I have the mgw shifter so I know it is not that? Also anyone change out their clutch with great results? If so what did you install?
 

Justin

Save the dawn for your dishes!!!
I have found that at top of third the clutch gets hard and wont come all the way back up for me till the rpms fall every once and a while. Then have to pump the clutch a few times to "clear" the extra firmness out. I dont know what causes that. Is that whats going on with your clutch?

When the day comes I will be going after a centerforce DYAD clutch set up. I had centerforce DF clutch in my 96 cobra with a tremec t-56 and I loved it. light clutch pedal but held lots of trq.
 
518
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I'm curious why you would suspect the clutch assembly itself rather than the clutch hydraulics?

Sure, putting a clutch/pressure plate assembly with a higher rate return spring might cure the problem, but I would try to drain/bleedout the clutch master cylinder, lines, and slave cylinder and replace the fluid.
 
I am not sure it is the clutch I am leaning towards the gears in the tranny it would come out of gear fast and fine feeling but would not go into gear almost like something was locking it out until the rpm came down? I did not have my track key in at the time and was also bouncing off the rev limiter. It actually felt like when you shift from 1st to 2nd and the 1-4 shift fuel saver is on how it locks you out?
 
jeepinocala said:
I am not sure it is the clutch I am leaning towards the gears in the tranny it would come out of gear fast and fine feeling but would not go into gear almost like something was locking it out until the rpm came down? I did not have my track key in at the time and was also bouncing off the rev limiter. It actually felt like when you shift from 1st to 2nd and the 1-4 shift fuel saver is on how it locks you out?
Sounds like the clutch to me. I've been saying this all along, most of the shifting issues are the clutch and related gear and not the tranny. I'm hoping to have more clarity on this by the end of Summer. It's either the springs in the clutch plate being overwhelmed by the last 800 RPM's and not fully disengaging or something to do with the combined clutch/brake master cylinder or combo of the two. There have been tranny's that are bad but if it shifts correctly most of the time I'd look elsewhere. When trannies go bad they go bad and intermitent shifting problems are usually something else.
 
i think the pedal not coming back up is going to be a hydraulic issue.
in fact, this whole issue sound the same as what the old ls1 vettes used to have going on with them 15 years ago
 
My clutch seems fine, I guess, the pedal went down fine it revs through rev limiter just wont go back into gear? it feels like the second gear lockout but with all of the gears only around 7500 rpm maybe 7600 it does go a bit over the 7500 mark. Today when I took it out I shifted at rev limiter each gear I had to wait to actually shift after pushing in the clutch. the clutch felt as if it was working to me just would not go into gear and did not make any weird sounds or anything just felt like a lockout. Is there an over rev lockout on this car?
 
I've had pedal issues, mine would not stick to the floor though. It would come up to about the spring bind point (based on the video that is floating around), stutter, then come up. I seem to have fixed that issue with a clutch bleed, but I have heard that doesn't work with the stuck to the floor issue.
 
CaliMR said:
I've had pedal issues, mine would not stick to the floor though. It would come up to about the spring bind point (based on the video that is floating around), stutter, then come up. I seem to have fixed that issue with a clutch bleed, but I have heard that doesn't work with the stuck to the floor issue.
Stuck to the floor is the slave cylinder most of the time.
 
I have not disabled the skip shift but. I decided to try again and see exactly what is going on and now I am determined it is a clutch problem nothing broken the clutch works great for a family car but NOT for this one at all. It reminded me of a race car with a stock street car clutch it cannot handle the rpm. It shifts great at any rpm except when you get right up to that rev limiter and even before I believe nobody can shift these cars every time without this problem showing up at 7500 rpm. I have the clutch line upgrade ready to go in but I am not wasting my time thats not going to fix this issue. Here is my thought-Ford went cheap on the trans and clutch thinking they could get away with putting the same stock crap from a stock mustang that does not go up this high in rpm and when they figured the problem they restricted the rpm even more in hope that nobody would come across this. this is my opinion ofcourse but anyone in this world building a race car with this type of engine 7500 rpm would never put a stock clutch in now maybe the trans may be just fine but the clutch answer is NO it cannot handle the force of 7500 rpm I believe this clutch should only be used up to 6200 rpm after that it is maxed out and then some. I had a really good chance to test it today and just so nobody says hey this guy is just another kid my credibility is, I have raced all my life I am 40 started out on dirtbikes at 8yr till 17yr durring the dirtbikes at 15yr I raced carts up to 28yr durring cart racing I raced hobby stock at 23 to 30 and in there are several camaro and mustang drag car builds. Last year I stopped racing a Hayabusa completely modified 225hp bike with a 100 shot of nos so this is not a new fast car for me I bought it simply because it is a Boss, it has almost 7000 miles on it and this is the first week I tried to shift it at 7500 rpm and I would say 4 out of 10 shifts do not work correctly. I believe if the car was limited to 7000 rpm shifts the clutch may do ok but for how long who knows. I also believe Ford will do nothing to fix their problem and if this goes out I bet it hurts sales on the 2013 model cause they are the same. I am thinking a new clutch pressure plate the whole nine yards and maybe even figure how to seperate it from the brakes this idea I believe was not smart at all.
 
I'm not having any high RPM shift issues, and I've likely made more than most. However, I have had 2 clutches give up already so I do have concerns about the ability of this clutch to handle the high RPMs and hp of the Boss. In both cases there was no noticable wear on either the clutch disc or pressure plate so it's not an abuse issue. At this point I'm still hopeful the clutch is up to the task since both my failures were separate distinct component failures. The first one was a spring ripping from the clutch disc and jamming between the pressure plate. The second was a failed (leaking) slave cylinder.

I have 30,000 miles on my GT500 clutch and probably 5k track miles with 640 rwhp which is 50% over stock and it's still rocking. The one thing I found peculiar right away on the Boss was the ease of the clutch pedal. The weight of the GT500 clutch has to be at least 3 times that of the Boss to disengage it. I was actually afraid to drive the Boss out of the dealer's showroom when I first started it because I literally didn't "feel" the clutch and was afraid I'd put it through the plate glass lol. It just seems like it should be heavier, but maybe that's just the effect of the assist spring they put in there to reduce the pedal force required to depress it.
 
cloud9 said:
I'm not having any high RPM shift issues, and I've likely made more than most. However, I have had 2 clutches give up already so I do have concerns about the ability of this clutch to handle the high RPMs and hp of the Boss. In both cases there was no noticable wear on either the clutch disc or pressure plate so it's not an abuse issue. At this point I'm still hopeful the clutch is up to the task since both my failures were separate distinct component failures. The first one was a spring ripping from the clutch disc and jamming between the pressure plate. The second was a failed (leaking) slave cylinder.

I have 30,000 miles on my GT500 clutch and probably 5k track miles with 640 rwhp which is 50% over stock and it's still rocking. The one thing I found peculiar right away on the Boss was the ease of the clutch pedal. The weight of the GT500 clutch has to be at least 3 times that of the Boss to disengage it. I was actually afraid to drive the Boss out of the dealer's showroom when I first started it because I literally didn't "feel" the clutch and was afraid I'd put it through the plate glass lol. It just seems like it should be heavier, but maybe that's just the effect of the assist spring they put in there to reduce the pedal force required to depress it.
have you tried to bounce off the rev limiter and then shifting not letting off at all? If so what rpm is your car rev limiting at? As far as your problem so far who knows they may just be defects. This clutch really feels as if it is beyond maxed out to me. I have been in alot of real race cars and the clutch is much much heavier and feels much more agressive this one feels like 'peanutbutter' an old saying when we could tell a part sucks and will fail if driven to the max.
 
I am going to test it again with the track key and a service guy from my dealer so they cant say well you were shifting it at redline he will already know. I am thinking to start at the pedal and start changing parts out. Just knowing this can happen is frustrating to me. My car has no other problems that I know of and it shifts good clean sounds right through out all of the gears. I was literally bouncing off the rev limiter not touching it then backing off when this happened. Hope it does not do it with the track key if it does there will be a youtube video real soon. This just makes me wish I waited for a gt500.
 
http://www.boss302forum.com/index.php?/topic/14258-clutch-sticking-during-high-rpm-shifts-how-to-fix-it/

I am trying this today hope to test by the end of the day.
 

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