I bought my 98 Z28 with k&n FIPK, I assume anyway. When cleaning the filter I wondered how it draws enough air when it is not fed by the stock arm from the front of the car. Secondly, I have flowmaster exhaust and appears there is no muffler. Somehow I think this flowmaster and k&n setup was put on to work together, I know this is stupid but I am not really knowledgable about all this, BUT I'm paying attention in here!

 

I'm personally not a big fan of the K&N FIPK for the LS1 f-bodies. I bought one right after they came out to test, and I wasn't impressed. I was running an aftermarket lid with the free ram air before that, FYI. The K&N FIPK pulls in hot air under the hood, compared to any lid that pulls the air from only the front of the airbox (and underneath if you have the FRA). I plugged up AutoTap once the FIPK was installed, and I immediately noticed that my inlet air temperature was hotter than it normally was with the lid. The FIPK may do decent once the car is moving and can get some cool air moving, but in stop and go traffic I was unimpressed.

As for the Flowmaster catback, you will get better performance from another system (such as Borla, SLP dual/dual, Hooker catback, etc.). The Flowmaster race mufflers flow very well, but the street mufflers aren't that great. I've seen an LS1 with a few bolt-ons (excluding headers) with a Flowmaster catback that picked up 7 RWHP by opening the cutout vs. running through the Flowmaster muffler. Some love the sound of the Flowmaster systems and happily run them, so you can sell the system if you do decide to swap to a different catback. Just make sure that it's the complete catback and not just a FM muffler.

Trevor - LGM

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