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Just ordered K&N Intake + Borla Catback

15217 Views 51 Replies 21 Participants Last post by  oarngemig
I decided to try this combo since everybody has been using Joe-Z.

K&N was $265 shipped and I forget what the catback was $1300 or so.


Installed the K&N intake... Sounds MUCH better... Sounds like a V8 should. You can start hearing the difference at roughly 2k rpm and full throttle it really does sound like a race car. The car no longer sounds like chewbacca when accelerating. Did not really feel the difference however that might of been because I was distracted with the sound which was LOUD.

Got the Borla cat back installed today. It sounds beastly. I love it. There is drone, but that's expected on an aftermarket exhaust. The car turns heads when I go over 2k rpm, every time.

At full throttle there is absolutely no comparison from stock to aftermarket. It is LOUD. It idles slightly louder.

It was definitely worth it for the sound alone, it sounds good and can get really loud. HOWEVER, Borla is known for making poorly fitted exhausts, and I was the recipient of one... The installer basically told me Borla f'd it up and if I hear rattling to come back and he's going to try to work with it. He said the exhaust might start rattling when it warms up, and it did. He said some guy had one put on his Mustang a week ago and same thing happened.

...So I'll have to go back which I really hate doing. I'll get sound clip up / vid tomorrow.
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phlabrasca the problem isn't your new exhaust it's that K&N intake. Get that thing off the car and you'll be happy once again IMHO.
Why do you say this? Personnal experience?
Have yet to see a 2IS with an open filter in the engine bay outperform the stock intake in real world driving or at the drag strip. Check out all the top performing 2IS cars on and you will see the trend.

...and yes I'm aware that K&N has that little divider wall that is supposed to limit the amount of hot engine bay air. Fact is it still draws in warmer air, Fact is this engine is not gasping for air as the factory intake provides more than enough for the hp level, fact of potential issues with the MAF down the road aren't good either.

Buy an intake like this if you want more sound and care less about true performance.
suprajones, dyno's don't always tell the truth (especially with intakes) and can sometimes mislead as I feel has happened here. Maybe what you need to do is a few pulls against another IS-F with the stock or joez intake. That should make up your mind. Do a few pulls from the bottom of third gear so the factors of wheel slip or launching techniques are void. Of course make sure fuel level is about the same for both cars and see what you conclude. For even more convincing data, how about doing some pulls later with the stock intake back on the car and compare the differences. If you have access to IAT's that would top things off as you'd know for sure the difference in temps with and without the K&N setup and obviously the cooler the IAT's the more power you'll be making.

And sorry to answer your question: The reason you won't see any open air set-ups posted is because none of them have yielded results worth posting. More of an embarrassment and eye opener IMHO.
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...And was smoked once again. This time I lose to a stock 2004 Mustang GT 0-80 :/ Jumped the line faster than me, and continued to get away from me. Sport mode without paddles.
That should never happen unless the Mustang was spraying or has FI.
I agree completely with your advice on comparison runnings of the car mentioned above. I have a couple issues here- only 1/4 mile is in Darlington Motor Speedway(1 1/2 hour drive) and there is only 2 other ISF's in the state to my knowledge via hear-say. I have thought about buying one of the digital meters I have seen on some you tube videos (measures 0-60 time and g-force I believe) Have not researched thier reliability or $ yet,,Anyone have opinions on this device?
Since the intake has been on my mind today, I popped the hood and checked on the fitment to make sure nothing was loose or leaking. After 2+ hours w/engine off and parked in an open air carport the intake pipe was scortching hot, im guessing around 130-150 degrees along with all other plastic and metal surfaces I touched. (odd that I can guestimate heat by feel=yes, comes with my line of work). Led me to contimplate some type of insulation wrap, kinda like people used/still do put on headers. Just a thought.
Insulating wrap won't do any good. The air is rushing in so fast that it won't have time to heat up. The air that the filter draws in will pretty much be it, which is why we in no way want any of the engine bay air getting into it.
Perhaps we should wrap the headers then, to decrease the engine bay temps.. Better yet, wait for some after market headers to be made so wrapping them before they are installed will kill 2 stones with 1 bird.

or you could just stick with the oem setup. Just sayin :cool:
I have a digital gauge to monitor IAT. If anyone in DFW (looking at you DFloreas :) ) would drive around for a bit, I can pull the data and post results of IAT vs ambient.
Here we go. (thumbs-up)
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