horns

IMO the race pipe loses character compared to stock below 4k. To me it is a bit boomy. In fairness, the dundon street headers and OE center muffler are also a bit boomy to me in the same rpm range though not as loud as the race pipe. It is just my suspicion, but I wonder if all options that delete the side mufflers have this characteristic. I'm not going back to stock because the stock system volume is lacking in a big way.

I'll also say that the race pipe volume is loud when just cruising at low rpm, but it's way, way quieter under those conditions than it is at WOT. WOT vs low load, low rpm is night and day. Be warned if you have family, the cold start, in the garage, is going to wake up your house. There is no sneaking out period.

hsb1001

I plan to make several videos of mine when it arrives with all different driving RPM Sounds. Having had 5+ different systems on my car, i wanted more of the RSR noise higher end but also something that sounds more prominent on the street lower down.

Atlas911TT

did you get race or silenced race?

krell

After loosening all four clamps yesterday morning and trying to get the exhaust back into place I failed. The tips are in the same spot as before I got under the car so clearly I'm doing something wrong. I really don't want to take it to my shop again to have them monkey with it but may go that route at some later date. I'm not driving much these days so it may be like this for a while.

drl

If tips are dropping, would adjusting the 4 clamps help? Seems adjustments need to be made farther back in the system.

krell

The adjustments are needed post cats, so the clamps in the system after that point are all that require loosening.

Jickel180

What helped me was loosening all 4 clamps, and placing a floor jack underneath to support the exhaust at the tips a little higher than the desired height. This made the exhaust where it meets at the cats to be angled upwards a little. I then tightened the clamps at the cats, and then the two clamps at the silencers. After removing the floor jack the tips dropped some as expected but the height of the exhaust is mostly where I want it.

drl

^^This was my point, it needs to be adjusted at the cats. I do what you describe, only without the floor jack, just holding up exhaust with one hand, tighten cat clamp with the other.

krell

I was under the car pushing up on the tips while a friend tightened the header clamps and the position of the tips didn't change.

Atlas911TT

https://rennlist.com/forums/991-gt3-...t-bracket.html

Soul commented on how to support GMG center section with their side delete. They recommended using Mikalor Band Clamps to fit around the CMB and the Lower factory tab. This may be the solution here. But maybe would need to hook it up to the upper tab give the curved pipes on the JCR.

Here is a photo:

drl

If you loosen the cat clamps, and loosen any clamps holding the rear section to the engine block (if you are using any), there is no way the exhaust, and also tips, cannot be moved up and down.

krell

I could move the entire exhaust up where it was supposed to be but it still fell after the clamps were tightened so I don't know what's up.

JCR-Porsche

Unfortunately it sounds like the clamps aren’t clamping. If the exhaust is not secured by the clamps once tightened and shifts even with the clamps bottomed out then they have stretched and lost their ability to properly secure the flange on the JCR part to the headers

I think you’ve found the issue. Thankfully a simple fix

JC

krell

They weren't bottomed out, but were torqued to roughly 20ft lbs. It's possible I could have gone tighter but you indicated that actually makes things worse.

Atlas911TT

Maybe JCR can chime in here:

you said it is not wise to mount the center bypass part of your race pipe to the oem mounts because of increased vibration......but Soul, Sharkwerks, and quick fixes like above for GRP/GMG are done. What makes your system different to not mount the center? Just curious....