the Official "NA Tuning" thread
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Originally Posted by wildcardtrd,Jul 5 2006, 03:35 PM
That blows...BTW, where did you get your AEM EMS tuned? Depending on who did it, there still may be more power there to extract...
The exhaust is a defenate letdown. I suspected 3" is too big, but more so due to the flow charteristics of our engines...we only flow 634.711 cfm at full song. A 3" exhaust is probably slowing the exhaust flow enough to build enough backpressure to cause the performance hit your dyno is proving.
The exhaust is a defenate letdown. I suspected 3" is too big, but more so due to the flow charteristics of our engines...we only flow 634.711 cfm at full song. A 3" exhaust is probably slowing the exhaust flow enough to build enough backpressure to cause the performance hit your dyno is proving.
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Originally Posted by 2QYK4U,Jul 5 2006, 06:01 PM
AutoWave did the EMS tuning and they have a lot of tuning experience. I don't believe anymore power could be realized through more tuning. Like I said before, the fault primarily lies with the exhaust design itself.
I went the opposite route and had them curve the pipe up and over the bar then angle it out the back.
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Originally Posted by HvRRZ,Jul 6 2006, 07:02 AM
Did you go with the straight through sedisn where they remove the rear tie bar??
I went the opposite route and had them curve the pipe up and over the bar then angle it out the back.
I went the opposite route and had them curve the pipe up and over the bar then angle it out the back.
1. There is no transition from the 2.5" header piping to the 3" exhaust piping. Some sort of "resizer" (I don't know what the heck to call it) was place in between the two brackets. From what Shawn Church told me, the transition from 2.5" to 3" needs to be very smooth or you will lose power.
2. The bend just before the rear tie bar is bad--instead of using a piece of prefabricated, mandrel bent, piping for the bend the shop essentially cut a ~45 degree angle out of two pieces of piping and welded them together.
So far those appear to be the two biggest flaws with the exhaust design. Furthermore, the welds are very bad, and while this doesn't impact exhaust flow it sure isn't professional looking.
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Originally Posted by 2QYK4U,Jul 6 2006, 08:23 AM
No, it is not a straight through design. The piping towards the rear of the car is curved up and over the rear tie bar. The problems with the exhaust design are as follows:
1. There is no transition from the 2.5" header piping to the 3" exhaust piping. Some sort of "resizer" (I don't know what the heck to call it) was place in between the two brackets. From what Shawn Church told me, the transition from 2.5" to 3" needs to be very smooth or you will lose power.
2. The bend just before the rear tie bar is bad--instead of using a piece of prefabricated, mandrel bent, piping for the bend the shop essentially cut a ~45 degree angle out of two pieces of piping and welded them together.
So far those appear to be the two biggest flaws with the exhaust design. Furthermore, the welds are very bad, and while this doesn't impact exhaust flow it sure isn't professional looking.
1. There is no transition from the 2.5" header piping to the 3" exhaust piping. Some sort of "resizer" (I don't know what the heck to call it) was place in between the two brackets. From what Shawn Church told me, the transition from 2.5" to 3" needs to be very smooth or you will lose power.
2. The bend just before the rear tie bar is bad--instead of using a piece of prefabricated, mandrel bent, piping for the bend the shop essentially cut a ~45 degree angle out of two pieces of piping and welded them together.
So far those appear to be the two biggest flaws with the exhaust design. Furthermore, the welds are very bad, and while this doesn't impact exhaust flow it sure isn't professional looking.
The transition of mine was not the best either although mine was from the test pipe back. I agree the welds do not look pretty at all, but they did seem to be well done, atleast to the point where you knew the thing would stay together. Mine had a similarity with the bends but it wasn't to bad. Mybe they went a little worse on yours.
By the way....maybe for the future made one you can go cat back. That way the 2.5 from header to a 700 mm test pipe to the 3 inch system might have a better transition.
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From: formerly versionJDM
ok boys, the 70mm is in. h-o-l-y shit buckets i love 70mm. the car is alive for the very first time. wow, wow, wow. ok so i just made a vid of the exhaust and snappy a couple of crappy pics.
presenting.....SPEEDFACTORY 70mm header back....enjoy,
vid is uploading now...
presenting.....SPEEDFACTORY 70mm header back....enjoy,
vid is uploading now...
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From: formerly versionJDM
...what other mods do you have? and how much did it cost altogether?