FX300/350 and SRT Headerback Impressions
 

Hey Guys,

I want to post up a review for my new clutch kit and the SRT headerback.

I am prepping the car for F/I, and am ticking boxes off of my pre-F/I check list (oil cooler is next). A clutch was a requirement, and it seemed to make sense to install an exhaust while the clutch was out.

I chose the FX300, or 350, or whatever it is in reality, because I wanted to retain some street-ability, yet have enough balls to withstand F/I. I chose the SRT headerback because it came with a front pipe and over pipe, and I didn't want to pay $1300, so I bought it used.

Install:
I had the installation done at my local dealer. I know the tech, and I trust him. I got a killer deal. Everything went well, and was smooth. We verified that there were no exhaust leaks, and the clutch was simple, and easy to install. I was surprised to find some minimal wear with only 1,8xx miles on the car. I have never launched it, and only tried the NLS feature a couple of times. I guess the guy at the port beat the piss out of it!

The exhaust was easy to install as well. The front pipe was a bear, but everything came out and went in without a problem. The SRT system is very well built, and the materials and construction are high quality.

Impressions:
The clutch feels completely different. The grab point is lower than stock, and the pedal pressure is certainly greater. If you're used to the stock clutch this one may even feel more vague until you're used to it. I've only put about 300 miles on the setup, so I haven't done any hard shifts, but it seems that the added clamping force causes the tires to spin a liiitle more down low. I assume I can do great burnouts now, but don't wait for that review. Once one is used to the pedal pressure, and the grab point, it's easy to modulate. There is still a grab zone, it's not either ON or OFF. The pedal bites a lot lower, so be prepared to give it some gas if you're on an incline, or you will stall. It's very streetable, but does require a little bit of a learning curve. I do not feel the car revving faster with the slightly lighter flywheel.

The SRT headerback is LOUD. The car sounds like a damn Honda now, but with a deeper tone. I almost regret putting this exhaust on compared to the stock unit. The car feels cheaper. It's not the quality of the exhaust, it's just me. I'll keep it on, but it is loud, and does drove at certain RPM's. It's not unbearable, like the 4" dump on my old f-body Camaro, but it's loud. There are times when you'll get out of the car, and your ears will be ringing. I'll have to get an exterior sound clip, but it does sound nice, especially at higher RPM's. In terms of power gain, it's too early to tell. The second day I had the exhaust on, it felt slower than stock. Today it feels like it did tune-only, and I'm hoping the car picks up a little more as the ECU learns the new front pipe and over pipe. Visconti says that I do not need to retune, and can continue to run his tune without issue. I'm curious to see what kind of power I'm making.

Issues:
I only have one. This happened maybe three times, and only happens when I'm downshifting. The transmission will grind when downshifting into 4th, and only for a slight second. It's not an audible sound, but you can feel it through the shifter. The car did not do this before, and I suspect it's because the grab point is a lot lower, and my foot is used to pushing in the clutch less with the higher stock grab point. Does anyone have any feedback, or experience with this? I have not tried quick shifting, but will do that as soon as I get 500 miles on the clock. As long as it doesn't happen at high rpm shifts, I have no problem adjusting my driving technique to avoid it on downshifts. I hope it's not installer error, but I cannot see how that would happen, or why it would only happen in 4th gear when I haven't had a prior issue.

The other thing is chatter when the clutch isn't depressed, but that doesn't bother me much.

Any impressions, feedback, etc., is welcome. Please let me know if you have any suggestions about the downshift issue. Maybe I'll adjust my grab point using the DIY on this site.

Had it grind going into 4th at high rpm today. I've felt it a couple of times now. Didn't do it before the clutch... wonder what happened. Are the hydraulics going out?

Adjust the clutch pedal to make it grab higher.

This is an idea. I found the DIY for that, but I also found a variety of threads with people that're having an issue with grinding going into either 4th, 5th, or 6th. I want to make sure that issue is addressed. Car is at the dealer right now.

Clutch is shaking like a m-fer... maybe something isn't balanced? The install was done by the dealer, and it went well. Clutch wasn't doing this after it was first installed. Found threads about the FX300/350 doing this on other car makes as well. Great!

What was the end result here? I'm looking at clutches for the same reason..pre FI install. Oil cooler going in this week and I want to install Perrin Motor mounts and FX300 clutch at same time.

I wonder if you bought a used SRT without the bigger resonators that were put on by some people (myself included) no issues having ears ringing for sure

There is no positive end result. The clutch shakes like you're stalling an 18 wheeler. It's worse when it's hot (after banging some gears). It likes to be slipped quickly, but I thought it would be more streetable than this. I have to say I'm not in love with it. It's coming out this week since I'm longer going F/I with this car.

I don't mind the loudness. It only does it when the windows are closed at about 3k. The exhaust is coming off this week either way.

@Sportsguy83 Another one bites the dust and another ones gone and another ones gone and another one bites the dust. I don't know why people installing a 10 lb flywheel think that they are going to get OEM like drivability. It isn't going to happen. There is a reason the OEM flywheel is as heavy as it is.

Mine still feels solid. Love it. Chad, I did engine mounts at the same time as clutch. Maybe that helped. Also have tranny mount insert and will install ForceFab John stiffener in a few weeks.

Agree 1000% with @King Tut. Expect a modified car to behave like a... modified car.. ding ding ding ding!

Lol, I'm all for the car feeling like it's modified, and being okay with the consequences that go with that, but this clutch has awful manners. This is worse than the much heavier duty combo in my 400+whp f-body, the 6-puck in my 500+ awhp Talon, and really any other high performance clutch I've had in any of my cars. My S/C Fox body Mustang had the harshest clutch known to man, and it didn't behave like this.

It's not that I can't handle clutch jitters, but this doesn't feel normal. The jitters get worse when the clutch heats up to the point that any sort of smooth take-off without significant rpm and quick slip is nearly impossible. It was fine for the first week, and then it gradually got worse. The flywheel looked great when it was going in, but maybe something was off. Subaru's do not like light weight flywheels, so maybe I should've just gotten the disk and resurfaced the stock flywheel. Who knows, who cares. As I mentioned, I've had other, better, stronger, clutches, and they never behaved this way. Not to mention the amount I paid for this damn thing...

I vote for improper install as I have the exact same clutch and don't experience any of the weird issues you mention. There is FW chatter when ambient is hot on idle and deceleration, but nothing bad. I honestly am extremely happy with the streetability of this clutch.

David,

Thanks for the feedback. Sounds like there is an issue either with the clutch/flywheel setup in WRBRZ's car or maybe an issue with the install. Hopefully he gets it sorted out soon. You have to take me for a ride in your car so I can check out the clutch (and the turbo now that you're dialed in much better). I want a clutch that can handle the extra torque without totally changing the feel. I don't mind increased pedal stiffness but harsh chatter and vibration gets old fast.

Chad

Definitely, probably E85 tune day would be perfect :D