Sooo, I'm a little slow getting the K&N Intake pics posted mostly because I wanted that 400HP mark...
I had my exhaust guy slap together some piping I picked out from Summit Racing and do a 2-cat delete (as we all know, there are 4 cats: two bolted to the turbos, and two bolted at the ends of the downpipe). What you're about to see looks jenky because the polished 304 stainless bends were on sale and cheaper than the non-polished 409 stainless bends. But because I was clearly trying to be cheap, the non-polished 409 straights were cheaper then the polished 409 straights. Trust me, I'm not proud of it, but for $450 total (parts + labor), the top-end gains were worth it:
Now that your eyes have been hurt, there are some interesting things to note about doing a 2-cat delete downpipe setup.
1) My setup is definitely custom: you can see that the S-bend is almost entirely removed. This reduces pipe length and restriction, and my exhaust guy felt that the mounts were sufficiently stiff enough that the 3/4" clearance I had with the chassis would never be a problem. So far, he's proven correct. You'll also notice that one side is actually further out than the other, and my exhaust guy got caught off guard after making two identical downpipes. I didn't even notice it at first, either, but looking at the factory ones also shows that the bends are slightly different on each side. Strange, because I didn't notice they weren't identical until I actually had the factory downpipes in my hands.
2) The loss of low-end and mid-range torque is off-putting. However, over a few dozen miles, the ECU adjusts, and you find yourself getting used to the more linear pedal feel instead of that "quick" accelerating lurch that 99% of cars from the factory come like. It does make the pedal feel "heavy", though. Not physically, but engine-response wise.
3) The gain in top-end power starts around 4K RPM, and combined with my catback and intakes, makes the 1-2 shift significantly harder to catch on the paddles/shifter. However, since every shift thereafter stays above 4K RPM, the increase in pull at this range is incredible and could easily equate to 400HP. I plan on getting a "baseline" dyno before I move forward with more aggressive mods like the chip and ECU tune I have planned.
4) Your engine and exhaust will become significantly louder. I noticed more growl in my exhaust, and resonance points are significantly more of a rumble than a vibration. The engine at full throttle is signficantly louder, too, as you're generating a lot less backpressure and a lot more pipe noise just underneath the firewall.
All-in-all? A downpipe + 2-cat delete brings out some power for sure. It makes your car growl more and pulls noticeably harder above 4K RPMs.
And no, I don't have any jokes for this 2-meow neutering mod.![[8]](/images/smilies/icon_smile_8ball.gif "Retarded [8]")
I had my exhaust guy slap together some piping I picked out from Summit Racing and do a 2-cat delete (as we all know, there are 4 cats: two bolted to the turbos, and two bolted at the ends of the downpipe). What you're about to see looks jenky because the polished 304 stainless bends were on sale and cheaper than the non-polished 409 stainless bends. But because I was clearly trying to be cheap, the non-polished 409 straights were cheaper then the polished 409 straights. Trust me, I'm not proud of it, but for $450 total (parts + labor), the top-end gains were worth it:
Now that your eyes have been hurt, there are some interesting things to note about doing a 2-cat delete downpipe setup.
1) My setup is definitely custom: you can see that the S-bend is almost entirely removed. This reduces pipe length and restriction, and my exhaust guy felt that the mounts were sufficiently stiff enough that the 3/4" clearance I had with the chassis would never be a problem. So far, he's proven correct. You'll also notice that one side is actually further out than the other, and my exhaust guy got caught off guard after making two identical downpipes. I didn't even notice it at first, either, but looking at the factory ones also shows that the bends are slightly different on each side. Strange, because I didn't notice they weren't identical until I actually had the factory downpipes in my hands.
2) The loss of low-end and mid-range torque is off-putting. However, over a few dozen miles, the ECU adjusts, and you find yourself getting used to the more linear pedal feel instead of that "quick" accelerating lurch that 99% of cars from the factory come like. It does make the pedal feel "heavy", though. Not physically, but engine-response wise.
3) The gain in top-end power starts around 4K RPM, and combined with my catback and intakes, makes the 1-2 shift significantly harder to catch on the paddles/shifter. However, since every shift thereafter stays above 4K RPM, the increase in pull at this range is incredible and could easily equate to 400HP. I plan on getting a "baseline" dyno before I move forward with more aggressive mods like the chip and ECU tune I have planned.
4) Your engine and exhaust will become significantly louder. I noticed more growl in my exhaust, and resonance points are significantly more of a rumble than a vibration. The engine at full throttle is signficantly louder, too, as you're generating a lot less backpressure and a lot more pipe noise just underneath the firewall.
All-in-all? A downpipe + 2-cat delete brings out some power for sure. It makes your car growl more and pulls noticeably harder above 4K RPMs.
And no, I don't have any jokes for this 2-meow neutering mod.
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![[:o]](/images/smilies/redface.png "Embarrassment [:o]")
![[;)]](/images/smilies/wink.png "Wink [;)]")
