My New Rear Section Exhaust
02-13-12, 09:07 PM
#1
My New Rear Section Exhaust
Changed the rear section of my exhaust last week. I had a full dual custom before, but the rear had crush bend pipes. The new rear section is Stainless Steel Mandrel Bends and I now have two inlets into the stock mufflers. Have a look and listen.
http://youtu.be/stqr-gE06TM
Lou
http://youtu.be/stqr-gE06TM
Lou
02-13-12, 10:23 PM
#3
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Nice Lou..!!
Congrats on being the first on letting us see "inside" the OEM muffler.
Just a heads up that the OEM mufflers have direction flow chambers.. So the inlet exhaust gases flow towards the front section, which then flows back through the perforated holes in each chamber and then ultimately flows out of the two smaller cylinder tubes that finally Exit out..
As shown in the cut out window of your muffler..
~ Joe Z
Congrats on being the first on letting us see "inside" the OEM muffler.
Just a heads up that the OEM mufflers have direction flow chambers.. So the inlet exhaust gases flow towards the front section, which then flows back through the perforated holes in each chamber and then ultimately flows out of the two smaller cylinder tubes that finally Exit out..
As shown in the cut out window of your muffler..
~ Joe Z
Last edited by Joe Z; 02-13-12 at 11:23 PM.
02-14-12, 04:50 AM
#5
Nice Lou..!!
Congrats on being the first on letting us see "inside" the OEM muffler.
Just a heads up that the OEM mufflers have direction flow chambers.. So the inlet exhaust gases flow towards the front section, which then flows back through the perforated holes in each chamber and then ultimately flows out of the two smaller cylinder tubes that finally Exit out..
As shown in the cut out window of your muffler..
~ Joe Z
Congrats on being the first on letting us see "inside" the OEM muffler.
Just a heads up that the OEM mufflers have direction flow chambers.. So the inlet exhaust gases flow towards the front section, which then flows back through the perforated holes in each chamber and then ultimately flows out of the two smaller cylinder tubes that finally Exit out..
As shown in the cut out window of your muffler..
~ Joe Z
Lou
02-14-12, 05:38 AM
#6
That was an option, but after cutting the stock muffler open, and seeing that it was well designed, we decided that continued use of it was a good thing. My goal was more performance with quietness in the cabin and that has been achieved. IMO, I made the right choice.
I'm assuming you're going to go dyno the car again? I know it's been a while and your results won't accurately reflect any gains if any, but if the numbers are no worse or slightly better then i'd say it was a good decision for you.
02-14-12, 08:33 AM
#7
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Thanks Joe. We had that drawing of the muffler before starting on this project. We decided that the secondary 1.75" pipe should go to the out side tube because it appears using that tube would avoid two of the reverse paths under full acceleration and still be able to enjoy near stock sound levels. I believe we achieved that goal.
Lou
~ Joe Z
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03-10-12, 07:14 AM
#9
Ran new Dynos last week with my new rear and modified mufflers. The results are almost a year apart, so really can't compare, but a good baseline in my mind.
Blue - Stock Exhaust Manifolds and Cats, Modified custom dual exhaust with glass pack resonators, X pipe and stock mufflers, Takeda Intake
Red - As above with PPE Headers and Magnaflow HiFlow Cats
Green - As above with new mandrel bent rear section and dual inlets into stock mufflers
I'm happy with the results, although I was looking for at least 390HP
Looks like the improvements come mostly at the top end.
I brought a friend up with me who also has an '08 F. He has PPE headers, no cats, a JoeZ exhaust and an Injen Intake. He had a run of 399+HP with smoothing set to 5. His other two runs were less spectacular because he was running lean and the electronics were retarding his timing.
Edit: To add new Graph for Friend's car compared to mine. He seems to be breathing better at the top end, above 5500 RPM.
Lou
Blue - Stock Exhaust Manifolds and Cats, Modified custom dual exhaust with glass pack resonators, X pipe and stock mufflers, Takeda Intake
Red - As above with PPE Headers and Magnaflow HiFlow Cats
Green - As above with new mandrel bent rear section and dual inlets into stock mufflers
I'm happy with the results, although I was looking for at least 390HP
Looks like the improvements come mostly at the top end.I brought a friend up with me who also has an '08 F. He has PPE headers, no cats, a JoeZ exhaust and an Injen Intake. He had a run of 399+HP with smoothing set to 5. His other two runs were less spectacular because he was running lean and the electronics were retarding his timing.
Edit: To add new Graph for Friend's car compared to mine. He seems to be breathing better at the top end, above 5500 RPM.
Lou
Last edited by flowrider; 03-12-12 at 03:21 PM.
03-12-12, 04:13 PM
#11
Lou, the graphs look good and my guess is the cats on your car resulted in the top end power difference and your slight advantage in the low to mid-range. You both have similar intakes, but I believe the difference between them can't be ruled out either.
I wonder how a stock intake would have changed things? I did back-to-back 400+whp runs with the stock intake and at 399whp for the other IS-F it may be something to consider if trying to reach the 400's. This car with headers and full catless exhaust seems to do very well this way.
I wonder how a stock intake would have changed things? I did back-to-back 400+whp runs with the stock intake and at 399whp for the other IS-F it may be something to consider if trying to reach the 400's. This car with headers and full catless exhaust seems to do very well this way.
Last edited by caymandive; 03-12-12 at 04:27 PM.
