I just recently purchased my RX-8 so I'm broke and I'm looking for some cheap enhancements to begin with. I have read through the existing threads and it seems that there are no really beneficial intake kits, but are there any gains from replacing the stock air filter? If so what is the best brand? I have heard some good things about the Green filter but I have no experience with that manufacturer.

Also does anyone have anyone have any other inexpensive modifications they recommend? I’m looking for the best performance/cost ratio to begin with.

 

Racing beat makes a replacement k & N filter,it's only $48.Also another cheap upgrade would be spark plugs.(nology or autoexe)Ther're like around $150.

 

What is the difference in performance gains with a K&N filter as compared to a cone filter?

 

You will get very little performance gain froma K&N replacement filter. One of the posters did a dyno with the Mazdaspeed version a while back & got like 1 hp, that is pretty consistent with what other people have gotten. With the cone type filter you are looking at 2-3 hp max. Honestly these won't do anything for your performance so don't waste the money. You are better off getting a midpipe (catalytic replacement pipe) & 02 sensor fooler that will give you 6-8 hp or save up for a Canzoomer ECU unit & tune it. Those are really the only decent performance gains for under $1000. You can get an aluminum flywheel but putting it in requiters taking out the tranny which can be very expensive. Other than that the only other ways is FI (nitrous, turbo, etc.). Good luck.

 

Fanman, thanks for the info. I will wait and add the midpipe later. I am not looking for scorching horsepower, as the 8 is our "family" car.

 

Probably the best performance part you can get will be to save up for the Canzoomer (will be about $1000 with the tuning by your local mechanic). It can give you from 10 whp to 22 whp gain & it make your car louder or less reliable. No other part will do that for you since this is your family car. The midpipe will help a bit, but realize it will be a bit louder.