NiteCrawlr

I haven’t. I thought about it but really don’t want to mess with it any more because I love the way it sounds right now. I don’t have headers (yet!) though just the rear and oap.

If you end up getting the set I would get the valve controller or have the valves permanently put on open though. The quality of sound at low revs is much better with valves open with the inconel rear and oap IMO.

dnimi123

I just got the plug and dynamat yesterday. Planning on doing this weekend. Will update... Regardless of the outsome of the symposer delete - do NOT hesitate to get the kline inconel OAP/Rear! It is simply the best sounding catback there is. Totally changes the car for the better. There is still drone but its almost the same as stock so its worth it (anyone who says these cars have no drone is immune to it or deaf!). Relatively quiet when valves closed and below 3,000 RPM. Just Do It!

Purekoryo

What’s the INNER diameter of the OAP section of the Kline exhaust? If it’s 2.5” and gets larger at the rear section I would think you’d gain and notice a bit more power. For example the Soul race exhaust is 2.5” and 30whp improvement over stock alone.

dnimi123

I did the Sound Symposer delete and its awesome. I posted my experience on that thread. I do have the Kline Inconel OAP/REAR and with the SS delete reducing the drone and overall interior annoying loudness... Im now considering the Kline headers!

Who has the headers and how much louder do they make the interior noise level? I dont care so much about exterior sound being too loud! Thx

808c2s

You should contact K-Nut. He has the full Inconel System. There's a You Tube video from Olsen Motorsports displaying the sound at full scream and cruising. Sounds really nice.

K-Nut

i have full inconel exhaust . Spyder , driving roof down all the time , even when cools.
I try to block sound simposium , no different, so I unplug it .
valves always open. If you driving normally it’s very livable car , if you punch it it’s get loud but not anything. I strongly believe Kline nail this exhaust perfect . Nobody on the marked have anything sounding so good.
200 cell cats.
only one think if you do not turn off auto stop/start when it turns off one bank of cylinders, it sounds really weird and pups . Not big deal I am not trying to save any money on gas anyway.

dnimi123

So just concerned about the car getting too loud again with headers. After the sound symposer delete, the noise level in the GT4 is really very low. so just wondering since im not worried about weight and already have the Kline rear/oap in inconel what do you think about just getting the Kline 200 cell headers in Stainless steel (to save some $$$)? Think it would be OK? And what if I jet coated them to to maybe make the sound a bit less as well. I really like to sound of my GT4 now, but want the power of the headers! Thanks for any advice!

jmartpr

Coating wont make a difference.....if you get the headers with cats it may be a bit louder under WOT in the upper RPMs....no cats, all bets are off, it will be louder....

dnimi123

so under normal operating sound should not be too much louder or gruntier with the 200 cell cat headers? If so then this may be my next purchase! Any thoughts on SS vs inconel for the headers? Thank you

K-Nut

inconel sounds little higher and more exotic, ss is little deeper also very nice , you can not go wrong either way .
sound is good with 200 cell , not to loud unless you go over 5k rpm
I have my valves always open and it’s ok , unless you push it

jmartpr

Agree with K-Nut......both materials sound nice and the cats will tame the sound.

TRZ06

This is what doesn't make sense to me.

It is reasonable unless you are pushing it over 5K. Isn't that where most will be often? In a car like the GT4, you are going to spend much more time in that upper range than most other cars. Maybe it is just tolerance level, but I wouldn't want it to be obnoxiously loud anytime I wanted to get into it some, that would get tiresome fast. And if you don't spend much time above 5K, that I kinda fail to see the point of having the GT4 at all.

IDK, maybe I am just getting old, but having a loud cabin and drawing attention to yourself every time you want to have some fun, well just doesn't sound fun to me.

K-Nut

if you want quite exhaust use stock , Kline is loud with valves open , quiet with valves close , get valve control and you will be happy .

spyderphile

Since you're in California, what are the implications of changing the Header with 200 Cell Cat? I read that non-stock Header will fail the visual inspection. And, will the Header pass emission test? I'll be moving back to California in a few years; so, trying to understand the impact. Thanks.

TRZ06

New cars are exempt from smog for the 1st 5 or 7 years ( I forget which), this includes visual inspections. You can renew online. So, you are good until then and if you keep the car that long, then you just need to "find a guy".