Hey everyone, I am new to this forum, but i do have a few questions concerning the gas mileage of the RX8 as well as trying to increase horsepower. I have owned several mustang GT's in the past, but did not like the new body style at all. (besides Ford owns Mazda anyway). My questions are as follows. I am looking to increase HP but try and save on gas. I was looking at going with a K&N typhoon intake, upgrading my pulleys, and a product that i am not familiar with is the Greddy exhaust. I am 39, so i am not looking for anything that sounds like a motorcycle. I am looking for something deeper. I have around 1400.00 to spend so i thought this would be a good start. If anyone can share any information on the products that i have listed or give me advice on what i should do i would definately appreciate it.

 

the best way to get you the HP you want is to go Turbo..... but it seems like you don't want to be that kid again.. next best thing is going Midpipe, but it will most likely throw a CEL.... Now with regards to the K&N typhoon, the 1st generation sucked ***, it made you lose power and it would heat soak.. Now the new one is better, but its still a Short ram intake so I would stay away from it, (not taking anything away from people who already have it)... your best bet is going with the AEM intake or the RacingBeat REVi w/ Air Duct.... Good Luck

 

I doubt you'll find anything which can do BOTH. The RB intake is a GOOD piece - providing nice gains over a large portion of the powerband. The RB exhuast is good too - very mellow sound, but deeper. Don't look for more than 5-10whp (Peak) gain...

 

if you are looking for a nice deep sound, you can not go wrong with a borla exhaust.

 

most of the non-turbo mods are good for sound... effect on power and mpg are almost nill.

 

Flame On!!

 

You're losing me: BETTER mileage AND MORE horsepower? Might be a job for that turbo vortex thingy that goes in your intake.

 

Borla and RB Revi intake will give you one of the most deep sounding combos without going overboard. It's about $600 for the borla, $300 for the intake.

Midpipe will take you to riceville as it will be too loud.

Far as better mileage, there isn't going to be much that will help you in that arena. You can try a taller 6th gear, but I doubt the cost will be worthwhile. A 4.77 gear and flywheel will give you more power and maybe help you get going using lower rpms, but again, the cost will outweight the gains.

 

I recently added the RacingBeat REVi w/ Air Duct and the Borla exhaust and it sounds great but I have already noticed a decrease in my gas mileage. I only average about 190 miles to a tank.....which obviously sucks

Then again it might me that everytime I get in the car I drive it like I stole it

 

do you get any in car rattles that didn't exist before the revi now? Only at 6k+ rpms?

 

I haven't noticed any additional rattles.....then again my radio shakes enough things loose on the car as it is.

I have noticed that my powerband has opened up a bit but I am also getting a dead spot in my acceleration between 6.5k and 7.5k.

 

FACT - mods that improve the noise are bad for gas mileage. Reason - they make you wanna step on the happy pedal more often just to hear it.

BTW, what do you mean by "upgrade my pulleys"? Is there something wrong with the pulleys on this car? Surely when looking at rotating weight, a lightweight flywheel and lighter/smaller wheels/tires would be the way to go?

 

Well smaller pullies are lighter and allow the engine to rev faster, which results to you as mr. driver , a more responsive car. Light weight flywheels and smaller pullies are a good combo for better responsiveness. These items really don't give you more HP, but actually free it up for more use over the rev band.

That was my first mod in my GT stang, smaller pullies to make the car more responsive on the throttle.

 

Lighter pulleys have no large effect on the 8's throttle response, people use underdrive pulley so they get better cooling at extensive high rpm use.