Two comments on With and Without Crossover Pipe
09-19-2007, 02:30 PM
#16
Race Car
09-21-2007, 10:15 PM
#19
Race Car
Thread Starter
Rear Muffler Bypass. It is an exhaust mod that replaces the rear muffler box at the back of the car with a pair of straight pipes. It saves weight, increases sound, but mildly and tastefully, and people claim that it adds 10 hp due to less restriction in the exhaust.
It is readily available for 1986.5 and later cars. (928gt.com, 928intl.com, + others) Easy to install, bolt-on modification. Some are stainless steel, which are nice, especially since these are your exhaust tips.
The 2 mid muffler/resonators remain in place.
Wish I had a picture handy. Hope this helps.
It is readily available for 1986.5 and later cars. (928gt.com, 928intl.com, + others) Easy to install, bolt-on modification. Some are stainless steel, which are nice, especially since these are your exhaust tips.
The 2 mid muffler/resonators remain in place.
Wish I had a picture handy. Hope this helps.
09-22-2007, 07:10 PM
#20
Burning Brakes
On my 85 the rear muffler does not unbolt from the 2 pipes comming from the mid muffler, so I cut it off and had 2 pipes welded up in place. I kept my exhaust tips and bolted them onto the "new" pipes. The tips use the same hanger directly over it that the old muffler used. I put the heat shield back on and fabricated a bracket that connects the other end of the shield to the other hanger that the old muffler used. It looks stock but does'nt sound stock. Will try to get some pics.
09-22-2007, 07:36 PM
#21
Race Car
http://picasaweb.google.com/tampapix...25005292373842
86 working on this as we speak look at the pumpkin carving thread!
chip X-pipe mid had RMB too loud got a ticket now this is where I'm at
86 working on this as we speak look at the pumpkin carving thread!
chip X-pipe mid had RMB too loud got a ticket now this is where I'm at
07-07-2010, 11:30 PM
#22
Race Car
Thread Starter
X-pipe Delete. Stock Cats back in.
M E O W
Really like the more civilized, low growl sound of the RMB. Very happy.
Anyone in Charlotte want a loaner X-pipe to try out? I don't plan on reinstalling it until I get my car track worthy again... several months.
Sanjay - you still out there?
M E O W
Really like the more civilized, low growl sound of the RMB. Very happy.
Anyone in Charlotte want a loaner X-pipe to try out? I don't plan on reinstalling it until I get my car track worthy again... several months.
Sanjay - you still out there?
07-08-2010, 12:21 AM
#23
Rennlist Member
What you are experiencing is exactly why I put high flow cats on my GTS with X-Pipe, Resonators and RMB. Lots and lots of people tell me they like the sounds.
Drive by Wav file
That being said, my 90GT with stock cats, resonators, and RMB sounded the best. I think the cam differences made it more musical.
Drive by Wav file
That being said, my 90GT with stock cats, resonators, and RMB sounded the best. I think the cam differences made it more musical.
07-08-2010, 01:04 AM
#25
Race Car
Thread Starter
For those new to the subject, Porken has a very impressive custom chip and tuning modifications that seem to work very well with free(er) flowing exhausts. Authothority and "eBay" chips are old news and possibly obsolete.
I stopped buying toys for my 928 a few years back. When I revisit the "toy store", the Porken agenda would be second on my list - second only to upgraded suspension.
I stopped buying toys for my 928 a few years back. When I revisit the "toy store", the Porken agenda would be second on my list - second only to upgraded suspension.
07-08-2010, 04:23 AM
#26
Three Wheelin'
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If your using Autothority chips you are just wasting gas. Its a complete fuel dump and does nothing but hurt your top end, maybe some low end torque with the extra fuel, but is terrible up top.
X-pipe is huge power increase, best dollar for HP on these cars. You should put your put rear mufflers back on and keep your X, or put highflow cats on the X.
Porken's chips are completely optimized through the full range and they are dynoed with an X pipe and show an enormous amount of power with that combination. He adds correct timing adds fuel low for torque and pulls back for peak HP. Also the S3 has bigger injectors than the S4 and with porkens chips you can use the 55psi regulator and have a low duty cycle on your injectors with lots of power.
X-pipe is huge power increase, best dollar for HP on these cars. You should put your put rear mufflers back on and keep your X, or put highflow cats on the X.
Porken's chips are completely optimized through the full range and they are dynoed with an X pipe and show an enormous amount of power with that combination. He adds correct timing adds fuel low for torque and pulls back for peak HP. Also the S3 has bigger injectors than the S4 and with porkens chips you can use the 55psi regulator and have a low duty cycle on your injectors with lots of power.
07-08-2010, 04:51 AM
#27
Rennlist Member
The difference in power between stock cats and RMB and X-pipe with high flow cats were that the car would spin the rear tires in 2nd gear by just flooring it with new Dunlop Direzza Star Specs like it did with Michelin PS 2s. Before the X-pipe/cats it would not spin the Star Specs in second just flooring it. No idea what kind of power increase that is, but it is enough to actually notice.
07-08-2010, 06:17 AM
#30
Three Wheelin'
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not sure what RKD is running, but Dave has highflow cats to go with the pipes both in 100 and 300. Roger sells the pipes, prolly sells the cats too. If you are doing something custom and going to weld, Magnaflow makes almost anysize, also in a few varieties of flow.