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update on my shifting issue

2K views 39 replies 16 participants last post by  Anthony05GT 
#1 ·
I let my tuner drive my car the other day to get a second opinion on the engauging / disengauging of my set up...right off the bat he said it was disengauging way too high on the pedal...then he took it for a burn.

He missed second gear himself first try! and he runs at the track every weekend and powershifts all night long.

He told me it was acting like it was overcentering and "hooking" is this possible on a hydraulic set up?

Another thing, not only is it engauging high on the pedal, but you only have to depress the clutch about 2 inches for it to disengauge and shift gears freely.

WTF?
 
#2 ·
Dude, whether you care or not it should engage up high which is a good sign. If it were engaging down low it would be all together different and a more common problem. I mean, the clutch should begin to slip when the pedal is depressed only a couple of inches with a hydraulic set up. That's normal. It's hard to say without driving the car or pulling the transmission out for a look, but I'm thinking one possibility is the disc is getting hung up on the input shaft due to the shaft possibly being slightly twisted. Have you been running drag radials with a lot of HP?
 
#3 ·
naw just street tires with around 560 Foot pounds of torque...is that enough to tweak it?

Ya sometimes it feels like the clutch hangs up down there. I i know what you mean about being high on the pedal...but this is REALLy high...and takes very little depression to disengauge....there is only 2000 miles on this clutch and engine...15,000 miles on the tranny....lots of 100 and 150 shots run thru it though.
 
#4 ·
Just thinking out loud, but the fact that it takes such a little movement on the pedal to get the disc disengaged kind of supports the idea that the input shaft may be twisted. You haven't been running drag radials, but some high speed forth gear engagements will twist it on street tires. Are you getting a ''nobody is home, door's locked'' shift or a grinding crunch when shifting at high R's and does it happen on every high R gear change meaning every gear?
 
#6 ·
The weird thing about that is most guys with our cars have that problem when the clutch engages close to the floor rather than way up high like yours. The point I'm making is if you stab the pedal a little and it's disengaged quickly (up high) then the rest of the pedal stroke should really get the disc far away from the flywheel resulting in a cleaner shift. I think I'd at least pull the transmission and inspect the shaft. No parts, just labor and get that idea out of the way and move on from there.
 
#8 ·
I know. I can't tell you how many times I've been ****ed by new parts.
 
#12 ·
In the July '08 issue of MM&FF (pg 140) there's an article tittled "Moment Of Release". Justin Burcham owner of JPC racing and the 2005 World's Fastest Mustang record holder says alot of shifting issues inherent in the S197's, particularly when adding hp, that are attributed to transmission/clutch problems are really caused by the factory slave cylinder being the weak link. Some aftermarket mfg's have built a stronger throw out bearing to handle the extra duty. Just food for thought. Here's a few links on the subject..

New: Ram S197 HD Adjustable Hydraulic Slave Cylinder - High Performance Stangs

2005+ Mustang GT hydraulic clutch problems - Ford Mustang Forums

Won't Go In Gear At 2nd to 3rd Speed Shift - IMBOC

Adjustable Slave Cylinders : Lethal Performance, Performance parts for Ford Mustangs

McLeod Industries: Frequently Asked Questions
 
#13 ·
We pretty much covered this possibility in the past. The problem is this guy's pedal engagement is the exact opposite of what you'd get when needing an adjustable release brg to cure shifting woes. I've got that McLeod release brg which really improved my shifts because my pedal was engaging closer to the floor. The fact that his clutch begins disengaging way up high on the pedal stroke suggests that his hydraulics are at least trying to give a full disengagement.

07stroker, I guess you have poly motor mounts? Also, keep in mind that different pressure plates offer varying rates of movement because of their mechanical design. What I mean by that is one brand plate will allow a different amount of disc disengagement than another brand that uses the exact same hydraulic system. I had several different Centerforce plates before getting one that had the correct geometry when they were starting to ship combos for the new stangs back in '05. The 3rd plate they sent me finally worked right even though all 3 looked the same to the naked eye. I actually used one of the **** versions on my son's car along with a McLeod release brg. It is still on his car and operating well only because the release brg is custom set up to the plate and it also offers .700'' of movement compared to the .500'' you get with a stock brg.

In your case I would first get the tranny out and inspect the input shaft and pressure plate. You may have a defective pressure plate causing the whole problem. A pressure plate's mechanical/moving parts can break/bend and cause all sorts of problems. I'd just pull the tranny, check all of this out first.
 
#14 ·
I ordered the spec 3+ from JPC thru Radmustangs.

I dont have poly bushings, my set up is in my garage. I have the torque limiters. I also got the low pressure pressure plate which was recomended to keep my pedal feel stock

And Mike i dont know man, I thought it was my shifter at first...is there any adjustment in the rod assembly on these cars for the clutch pedal?
 
#18 ·
OK, that just eliminates everything being tied up too close together. For example, if you have the slave/brg too close to the pressure plate it will cause the lack of free play, but shouldn't affect the shifts, just prematurely wear out the throwout bearing. Your going to need to pull the tranny and probably find a pressure plate issue or a twisted input shaft more than likely. There's only one way to find out. I'd bet it's in the bell housing.
 
#19 ·
My input shaft was twisted from 585 tq... the Spec 3+ clutch was completely shot.. and I never speed shift... I don't know what HP your were making but I was around 550
 
#26 ·
so...i pull the motor and all is good. i install forged goodies heads and a clutch....then right away clutch pedal feels like this......did i twist it while instaling the motor?
 
#30 ·
No, that's not possible. Your problem really is still a mystery, but it's also able to be fixed. I think something is wrong with your new combo in the bell housing. If by chance the input shaft is twisted the tranny has to come apart to replace it. I'd like to hear more or as much information as possible about how this clutch is feeling different compared to what you had going on before. How much more power are you running? What rpm's do you have this new problem? Only at high R's or anytime or what? There's definitely an explanation for this bullshit.
 
#31 ·
Okay.

Before the build last year i was bolt ons plus a 100 pill on the stocker...never a problem dynoed at 360 440 torque

Over the winter i jerked it, added a 298 livernois stroker, livernois stage two heads, Billed steel flywheel with spec 3+ clutch, headers, VCT limiters, gt 500 dual pumps with 39 pound injectors. Did it all myself, and yes i used the centering tool that came with the kit.

Put it all together , went to back the car out of the shop and noticed it right off the bat, very chattery in reverse and the pedal was engauging high on the pedal...but with it being brand new i thought I would give it its break in period. pedal felt like stock for pressure (Low pressure pressure plate? Ask Justin) went straight to the dyno in the car hauler and had it tuned. did about 7 4th gear pulls on a Mustang dyno. Layed down 310 300 torque (dont ask) Trailered it home and began crusing to break not only the clutch in but the motor as well.

First night out with around 150 miles on the clutch i got on it a bit cuz my buddy wanted to mess around a bit...thats when I noticed it was hanging bad in the upper rpm's Ran fine just crusing...and still does...but from day one up at 6500 RPM which is where i shift, it feels all wrong...it engauges so high that i usually am back on the throttle way to soon and it over revs before reengauging...if you know what i mean...i cant get a clean shift in either way.

Now ive re learned to drive the car a bit but I know this isint right. Im running a 150 pill now and have no idea where im at for power because the mustang dyno i put it on 2 weeks ago said i layed down 336 466 torque???

Any every now and then the pedal feels gritty going in...not all the time but every 5th or 6th shift i can feel it in the pedal.
 
#33 ·
clutch setup sounds 'off'.

Im sure you have checked the obvious, tob, etc.

which clutch, pres plate, flywheel setup are you running?

did you have flywheel and/or pressure plate resurfaced?
sometimes, this will effect the tolerances enough to compromise engagement as well as disengagement.
 
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