Are 20's a performance killer?
 

How much do my 20"s actually hurt my rwhp and overall performance of my car? I know they ride well at high speeds. I have a long stretch of highway(about 13 miles of 4 lanes with median)that doesnt have a lotof traffic and I have gotten her 130-150mph several times. The z rated Eagle HP's have held up pretty good so far. 28,000 K miles and counting.

I really dont want to buy more wheels, because this is my second set, not including stock.Just wondering how everyone else has faired, 20's or not.

RE: Are 20's a performance killer?
 

i dont know what section it was in, but i believe that someone with an S197 GT had their car dyno'ed with stock wheels and with bigger wheels (i think that they were 20s, but im not 100% sure) and there was a noticable difference in the output with the bigger wheels.

RE: Are 20's a performance killer?
 

RE: Are 20's a performance killer?
 

YES!!!All day long andtwice on Sunday. They hurt ride quality, soak up power though increased rotating mass, suck for handling,plus to me personally they ride on the edge of looking goofy on these cars, some more than others. 20"s and up look good on some cars but don't go with others. Would you wearStacy Adams(or another high class shoe)with a track suitor vice versa?

RE: Are 20's a performance killer?
 

I think I've read around 20-25 RWHP depending on the weight of the wheel/tire package.

RE: Are 20's a performance killer?
 

What about the Saleens? That is where I got the idea to go 20" in the first place. If I had an additional 20-25 rwhp by going back to 18" or 17" I would do it in a heartbeat, because Im pushin 310 now. That would have me up to 330-335rwhp. Thats just enticing!! LOL

RE: Are 20's a performance killer?
 

someone dyno'd and it made a 8rwhp and i think 6ft tq difference with the 20's rather than the 18's

RE: Are 20's a performance killer?
 

not only are they heavier, and have more rotational mass, but they effectively change your gear ratio to a numerically lower one.

RE: Are 20's a performance killer?
 

No they don't, that only happens if you use a tire with a larger diameter than stock. Most people use a really low profile tire to avoid speedo issues, etc. I would personally go with a tire a little larger than stock if i had to have 20's. I've bent 17's with more rubber than some of these guys have between their rims and the road.

20-25rwhp difference is a little high. I've only heard of one test done and 10 rwhp was the difference. Some people saythey can feel a difference between the 18 vs. 17 as far as acceleration goes, but IDK about that.

RE: Are 20's a performance killer?
 

rotating mass hurts . . . and it changes your gear ratio . . . if you originally were a small tire diameter wise, it would make your gearing higher . . .

3.20 ish as to 3.55 ish etc