Stock Exhaust vs Modfied Apexi WS2

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Jun 24, 2007, 02:52 PM

incog6

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Stock Exhaust vs Modfied Apexi WS2

Vehicle: 2006 Evo IX
Stock Exhaust vs. Modified Apexi WS2

Stock Exhaust
-stock dp
-stock catalytic converter
-stock catback

Modified Apexi WS2
-stock dp
-RRE Rally cat
-modified WS2 midpipe: RRE 3x24 SS Resonator, 3" SS piping, RRE SS o2 bung, RRE SS 3" flange
-unmodified Apexi WS2 axle back

The following aural tests were with a Radio Shack Sound Level Meter (33-2055). Weighting A tests db ranging from 500hz-10000hz *human ear range. Weighting C test db ranging from 30hz-20000hz.

Stock Exhaust:
Idle:
-Weighting A:
3ft away from tip: 81db
10ft away from tip: 68db
-Weighting C:
3ft away from tip: 100db
10ft away from tip: 87db

3K:
-Weighting A:
3ft away from tip: 83db
10ft away from tip: 75db
-Weighting C:
3ft away from tip: 94db
10ft away from tip: 85db

5K:
-Weighting A:
3ft away from tip: 87db **fluke?
10ft away from tip: 85db
-Weighting C:
3ft away from tip: 91db
10ft away from tip: 85db

Modified WS2:
Idle:
-Weighting A:
3ft away from tip: 80db
10ft away from tip: 71db
-Weighting C:
3ft away from tip: 98db
10ft away from tip: 88db

3K:
-Weighting A:
3ft away from tip: 86db
10ft away from tip: 79db
-Weighting C:
3ft away from tip: 98db
10ft away from tip: 91db

5K:
-Weighting A:
3ft away from tip: 87db
10ft away from tip: 84db
-Weighting C:
3ft away from tip: 94db
10ft away from tip: 86db

*****movie clips to come
*****70mph cruise and WOT test results to come
Apexi WS2 midpipe

Stock Cat vs RRE Rally Cat

Stock Cat Weight

RRE Cat Weight

Modified WS2 Midpipe (top) vs Unmodified WS2 Midpipe (bottom) *less 3" portion

Finished Product

Last edited by incog6; Jun 24, 2007 at 02:59 PM.

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Jun 24, 2007, 09:19 PM

TS8

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Excellent results if you want a quiet exhaust!

I have the WS2 , Apexi GT Downpipe and Works 3"HFC that I will be installing soon.

However, I noticed that the midpipe inlet for the WS2 is made for 2.5"(stock) cat.
Did you fabricate the midpipe yourself ? I am looking/ considering cut and weld
a 3" flange for the midpipe inlet.

Please let me know if you consider selling the midpipe. Thank you.