SPEC STAGE 3 Clutch Fitment

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
I decided after much consideration, to have a shop install my brand new SPEC Stage 3
clutch instead of attempting that job myself...

Low and behold, the shop calls and reports that everything fits except the splines on the
input shaft don't exactly match those in the clutch. WTF is going on? Don't a bunch of other
people have SPEC Stage 3 clutches in their STi's (mine's an '04).

The shop owner said he could file the splines to make it fit, but of course that's not the
best way to remedy the problem.

Idk what to do... Has anyone run into this before? Is it possible that I was sent the wrong
clutch for my car?

Thanks guys!
-Ryan
 

IGOTASTi

System Operator
Staff member
Who did you buy the clutch from? Also do you have a part number?
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
I believe all that info is in the car at the shop. I'll look around quickly and see if I have the invoice
here. I'll PM you as to who I bought it from, don't want to throw him under the bus...lol
 

ZachTTLM

New member
part number will help, I can reference the number to make sure you got the right part to start with...
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
Bazinga! Get that person to send you the right clutch buddy.

Idk if it's the wrong clutch yet...

I've tried calling him. Left a message but haven't heard back yet. It hasn't been more than 30
minutes so I'm not too upset yet or anything. I just need to provide a timely response to the
mechanic so we can figure out what to do.
 

ZachTTLM

New member
wow seems like everyone posted at the same time there.. anyways that is the correct part number... now check the disc to make sure it is the right one. It should have the part number on it as well..dont just look at the box. How reliable is the shop you have this at? what methods did they use to check the splines? Did they just have issues getting it to go in while bolted to the engine or did they test the disc itself on the input shaft?
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
That's a definite possibility. I've seen things like that happen in the past. That'd be a shame though if that's the case.
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
wow seems like everyone posted at the same time there.. anyways that is the correct part number... now check the disc to make sure it is the right one. It should have the part number on it as well..dont just look at the box. How reliable is the shop you have this at? what methods did they use to check the splines? Did they just have issues getting it to go in while bolted to the engine or did they test the disc itself on the input shaft?

They said everything bolts up just fine and you can run through the gears with the clutch engaged and the engine off, all the normal stuff. When they tried to start and move the car they said the clutch wouldn't disengage. After disassembly and inspection they find that because the splines seem slightly mismatched, the input shaft is not pulling the clutch back off of the flywheel. (or at least that's how I understand him)

It's a reputable shop. They specialize in transmission work and do a million clutch jobs. The shop owner is pretty trustworthy.
 

ZachTTLM

New member
That sounds like a faulty throw out bearing as fuji said or air in the clutch line system that needs bled our more than spline misalignment...
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
I just talked to him again. He said the clutch does go on the input shaft, but he'd
have to tap it on forcefully with a hammer, not sliding on nicely like it should. Of course
that causes the problem we already have.

He said there is no part number marking or reference on the clutch or pressure plate
at all whatsoever other than a SPEC sticker.

Also, he examined the splined closely and said the casting work doesn't look sloppy
like a manufacturing defect of anything, it's just most likely the wrong clutch...

He COULD file the inner spline groves in the clutch to make it fit smoother but we're
both not sure how much we trust that idea.
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
Just wanted to check buddy. If grease isnt enough to let her slide freely and the TOB is new and the clutch line is bled... it may come down to filing it slightly. I would also be hesitant to do that, but sometimes a fix is a fix.

Thanks man. Yeah, I don't know. I got ahold of the vendor, he is baffled and gave me SPEC's tech line. I called
them and they are closed until Monday the 9th for the holidays. FML!
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
Roger that, I'll be sure to reitterate that to him. We're going to wait to do anything more until Monday morning when we can
get in touch with SPEC.
 

IGOTASTi

System Operator
Staff member
Roger that, I'll be sure to reitterate that to him. We're going to wait to do anything more until Monday morning when we can
get in touch with SPEC.

Good deal. Better to be safe then sorry. :)
 
I decided after much consideration, to have a shop install my brand new SPEC Stage 3
clutch instead of attempting that job myself...

Low and behold, the shop calls and reports that everything fits except the splines on the
input shaft don't exactly match those in the clutch. WTF is going on? Don't a bunch of other
people have SPEC Stage 3 clutches in their STi's (mine's an '04).

The shop owner said he could file the splines to make it fit, but of course that's not the
best way to remedy the problem.

Idk what to do... Has anyone run into this before? Is it possible that I was sent the wrong
clutch for my car?

Thanks guys!
-Ryan

Not trying to troll or start crap but this will most likely turn out shitty for you. I hope I'm wrong but I bought the same clutch from Defined Performance for my Evo 9 MR and had an Evo exclusive shop do the install and they ran into the same problem. Originally the vendor and SPEC tried to blame the installer (which is a joke) but after SPECS' "tech" people talked to the installer they came to the conclusion everything was done correctly (shocker)! Defined then had me send my clutch out for inspection to SPEC like he will probably have you do. Before sending the clutch I asked SPEC if there was any possibility that the clutch was defective and the tech said it was a one in a million chance. Well after wasting 40 bucks shipping the clutch and having the car down another week SPEC came back saying the clutch was fine and not damaged during the install so the issue must be my car. Sounds logical even though my installer told them my car was fine, so instead of having my installer try the SPEC clutch again and risk having to pay for 2 installs I bought a similar Exedy and it went in with 0 issues. Basically I think you're going to be left with an expensive paperweight unless they happen to say it is indeed defective. I should have known better when my installer (Owns and operates the premier Evo shop in Colorado and the surrounding states) asked me what brand of clutch I got, cringed and said SPEC clutches are garbage. Feel free to PM me for additional details, it really sucks man good luck.


(If this offends the mods feel free to edit or take the post down, just sharing my experience with the OP)

EDIT: I took out how the vendor handled the issue and sent it in a PM to the OP.
 
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Eh, I had a buddy that his car tuned by him and made "411 HP" on tobz dyno. Then he went to revolutions Dyno and only dynoed at 302 hp...I like jacks transmissions, u can trust those dudes, not to forget, Kevin@jacks Is probably the best DSM/EVO Street tuner in the state

Revolutions does their dyno different than most shops. I don't think they give you corrected numbers so they will always be lower than any other shop. They tuned my stage 2 STI and it only made 245 whp on their dyno and I had MAC Autosport dyno it here in parker and the car made over 300 whp. Dyno numbers don't mean anything, it's all about trap speed.

Not an expert in dynos in anyway, shape or form so I might have that bass ackwards.
 

Vermont

New member
Revolutions does their dyno different than most shops. I don't think they give you corrected numbers so they will always be lower than any other shop. They tuned my stage 2 STI and it only made 245 whp on their dyno and I had MAC Autosport dyno it here in parker and the car made over 300 whp. Dyno numbers don't mean anything, it's all about trap speed.

Not an expert in dynos in anyway, shape or form so I might have that bass ackwards.

Also I wouldn't bring my Toyota Celica to Revolutions....
 
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