garyever

It only took me 5-6 track days after deleting my side mufflers at 23,000 mi. to blow a hole the size of a hardball through the middle section of the front side of my center muffler with numerous cracks extending to within 9" of each end. Stock engine, no ECU tuning, and no backfires other than an occasional throttle lift poping normal to 2007 .1 GT3. The front side looked to be in perfect shape at the time of the side muffler delete. . The extended cracks looked like vibration fatigue working its way from the center to the ends slowly creeping out both directions to destroyi the entire front side panel. Am now welding the cracks and covering everything with a stainless cover plate full length of the front side of the muffler to see if that will serve as a suitable repair and will post an update if it holds up or not.

Anyone contemplating a side muffler delete should consider reinforcing the frontside of the center muffler before deleting the side mufflers.

CosmosMpower

Good info, thanks for sharing. I love the sound of my GMG center bypass with stock side mufflers, perfect volume and pitch. I really don't want to deal with finding a stock center section and then re-enforcing it so it doesn't blow up.

mmuller

I have done this. Twice, on two box's. Crack, repair, crack again. The reality is, the whole box is to thin wall and not suited to constant, high rpm. Even the cup center's crack and they are thicker.

I eventually put a whole RSR style system on, that is thicker wall and better quality of stainless. It has lasted significantly longer, but it will eventually crack. These days, I break the straps holding the box on as its clear the vibration problem moved. Thankfully, they are cheaper than repairs where and easier to keep spares in the trailer.

Spyerx

Whose side delete pipes did you use?

This is interesting, I've well, a LOT of days and my center is perfect. The cup center has same internal design and metal gauge, buddies have this and we're not blowing the rears out.

Now, i have seen the TI mufflers blow for sure.

ScottArizona

Easy and free 13 lbs right here:

https://rennlist.com/forums/997-gt2-...with-pics.html

David911

Can't speak for everyone, but for me the best place to reduce some weight is the driver - 10lbs would be great. Cheapest option as well. Need to stop

Just sayin,


David
2008 GT3 - yellow

tcsracing1

Side muffler delete
light weight battery
euro rear bumper
carbon discs
CGT buckets
OMP steering wheel
BBS wheels
remove headlight washers
Euro rear window

You can also remove/shave the foam from your carpets.

I installed Cup doors for a stint...

jonwb

Thanks for the reminder on that one... I don't think I've ever used the headlight cleaning function (short of accidentally pushing a lever the wrong way).

garyever

I bought the Fabspeed side delete pipes that have two pipes into the L & R ends of the center muffler. I then pulled the side mufflers off and noticed that the OEM top pipe into the center muffler has an accordion section in the middle of the top connection pipe to handle heat expansion and/or vibration forces and wondered if the solid fabspeed connection was going to present a cracking problem, but then I noticed that that the top fabspeed pipe does not chinch tight into the center muffler unless the female fitting of the center muffler is altered with a hack saw cut to allow it to compress, so I deduced that Fabspeed had contemplated that expansion movement in their design. Then looked at the internal design of the center muffler and could see the top connection should have been deleted and plugged for the best exaust flow, but I had already bought them so installed them anyway. Some of the L and R pipes where slightly different lengths and one of the flair connections had been flared slightly too small to couple exactly right with the Cat, so the install didn't go well either, but being a glutton for punishment, I made it all fit. All together, the Fabspeed experience was a trying one and no big surprise when the center muffler blew out. My muffler crack welds and reinforcement panel have held out through a couple track days now, so that may be a reasonably inexpensive fix for the a cracked center muffler that can be done by any muffler shop. I have a great sound (not too loud), no drone above 2500, and the car is definitely faster now.

garyever

COSMOS---You might consider switching to the Tillett B1 carbon seats I am installing. 6.6 lbs each seat plus 8 lbs. vehicle specific aluminum mounting brackets & seat slider. All reviews I have read say they are very comfortable and are designed for you to also retain your 3 point seat belts if you wish (no buzzer or dash warnings). My 2 OEM Porsche manual Sport seats weigh 116 lbs, (I weighed both on my medical scale at 58 lbs.ea) - 29,2 lbs = -86.8 lbs. net reduction. $1500 ea (they list at $1800, but Tillett uUSA will give them to you for $1500}, so expensive, but in the world of light racing seats these can't be beat and anything close is min. 24 lbs ea, seat plus and $2200 ea. up to $5000 ea.

[url]https://www.tillettseatsusa.com/tillett-b1-carbon-seat[/url

My 2007 GT3--- dedicated track car with--- Rear roll cage, ExE-Tc suspension, Solid links F&R, Numeric, Sun roof, chrono, console, tools, cup lip, guard LSD, 1/2 tank gas

3286 lbs Corner weight total less driver
-15 lbs LWFW
-44 lbs side muffler delete
-45 lbs 18" Forgeline light weight wheels and Hoosier slicks
-30 lbs Braille 15lb battery
-87 lbs Tillett B1 carbon seats
_______
3080 lbs Total