my car (S5 n/a) seems to loose a noticable amount of power when its hot out side (25+ degrees) i was thinkin of getting a cone filter to help my car breathe but im not sure if i should spend money on that.. any body know why this is happening?

o yea it doesnt hesitate around 3800 and it doesnt overheat

 

it's only $30 for a cone filter, it's definitly worth it....

wish i could help you with the lack of power though but that could be a couple different things....

how hot does your car run when it's "hot"...?

 

i was thinkin of the apex filter (140$)
and i dont know how hot it gets

 

no no no, $140 is WAY too much for a filter, remember at autodream, mine only cost $30, works like a charm!, trust me!...

there's a pic on my cardomain, just click the link too the site in my sig.

 

If you still have the stock cooling fan, it could be a function of the fan working harder to draw the heat out of the radiator. If that's the case, you should hear more fan noise from under the hood on hot days. That will draw a lot of power on a hot day.

 

Do you have stock Cat's?

 

I picked up my Apex filter for 99 US from rx7store.net (I think it was). Granted, probably overpriced for what you can accomplish with a universal filter, however it is a very nice piece, and it only fits S5's making it a bit exclusive.

As for your S5 NA, mine is slow too, get used to it.

It's very weight sensitive (I notice a pretty big difference with just one other person riding along), it's temperature sensitive (hot days suck the power out of it), and it's very fuel load sensitive (as soon as I pass 1/4 tank it starts zipping around like it's cut loose from some shackles or something).

 

yea ill probably pick up that filter from autodream on tuesday.

i have the stock cooling fan but i dont think thats the problem cause i dont hear the fan noise on hot days

and no i dont have stock cats

 

If you put a cone filter in the engine bay you will probably slow the car down significantly on hot days and just all around, all the time. You need a true cold air intake or a sealed airbox/hood scoop to make any performance gains. I would get an electric fan instead of a $100 cone filter.

 

What he said ^^^^

Cat's might be clogged.

 

do you only notice the drop in performance when you are driving slowly around town, or also at speed on the highway?
if it's only during slow driving, this is simply heat soak. if everything is working fine you shouldn't notice too much of a difference, but it will be there.

not only is your stock clutch fan working harder, but the hotter intake temps means a less dense air charge.

as for cone filters, the $30 ones should be OK, but i recommend getting a K&N. you have an S5 AFM, so you can just get a 2.5 inch ID cone from them and slap it on. you can also search the forum for ideas on a "cold air" setup...
www.knfilters.com

 

A cone filter will cause your engine to run even hotter since it's only taking in heated air from inside the engine bay... at least the stock intake draws in cold air.

 

not if have a cold air box