Just thought a few notes regarding performance mods on cars may be interesting. (found while surfing, not MY figures)

1) Wings - Any wing fitted at an horizontal angle offset between 6 to 20 degrees adds aproximately 60kg (132lbs) of downforce at 100km/hour (62mph).

2) Mufflers - Add less than 3% power gain on a naturally aspirated car and less than 5% on a turbocharged car without a customised exhaust. Add a custom manifold or dump pipe back exhaust and you can increase that to 10% and 20% respectively.

3) Air filter - good for 3%-10% and is very dependent on the car.

4) Bodykits. -Veilside and Bomex kits are actually quite good for front downforce and reducing air turbulance, but most would only provide a marked gain in performance if the car was travelling in excess of 300km/h (284mph).

5) For the price of a painted bodykit for your standard civic, you could purchase a filter,ecu chip,headers and exhaust that would be good for about a 40% power increase on an EK3 Civic (1500cc) Thats pretty respectable!

I converted the metric to SAE, so they aren't quite EXACT, but close enough for goverment work.

 

i am not sure about that wing thing......i think that it also depends on how high the wing is..my brother(engineer) was saying that it is actually not that much...i will ask him for the figures and post them asap

 

the spoiler on my car acutally crerates life but it does give me a slightly better c/d.