I put these on last year and really like them. There is no distinct sound change that I can tell and they did add a few HP from stock. If you look at my sig, you can see what my overall HP/TQ ratings are with these intakes. HFC and CBE installed (and tune).
They do lower the intake air temps (usually I get about +10° higher than ambient) which is more than with the stock intakes.
I have no "skin" in this post, just wanted to give an opinion and help out another "old fart"
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