i have stock rims 17' on my evo is it true that once i get 18' my car will be slightly slower or is this a myth

 

if it weighs more of course it will be slower.

 

More rotating mass = slower car

 

o i c how much loss of power like 8% 5% 3% ?

 

more top end speed

 

Mythbusters says: Plausible

 

Amount of loss will vary depending on weight vs stock, and the distribution of the weight of the rim.

 

i 2nd that

 

negligable

 

If the Wheels weigh More, yes.
If the Wheels are Slightly larger than stock, you will accelerate slower.
If the Wheels are Cool get them, you won't notice the Difference.

 

Not a loss of power. You will still have the same amount of power but that same amount of power will be pushing something heavier. So it will be a lil slower.

 

lol if only we had this frame of mind about everything haha made my day

 

The stockers weigh roughly 20 lbs--there are numerous rims that are bigger and lighter, so just look around if speed is that much of a concern to you. The difference shouldn't be too noticeable unless you auto-x your car

 

If you are worried about the wheels slowing you down that much, your car isn't going to be fast enough for you anyway.

 

yes