Power loss with 20's?
11-28-2006, 07:35 PM
#33
5th Gear Member
Join Date: Mar 2006
Location:
Posts: 2,544
RE: Power loss with 20's? here we go again!
Hah! I love this! Just as much fun as thermo lab!
I think it would probably be best to model a rim as about 1/3 a flat disc (representing the "spoke" area) and a hollow ring of the remaining 2/3 of the weight, for the tubular section where the tire actually sits.
But yeah, Sleeper's numbers may not be 100% accurate, the idea is solid.
I think it would probably be best to model a rim as about 1/3 a flat disc (representing the "spoke" area) and a hollow ring of the remaining 2/3 of the weight, for the tubular section where the tire actually sits.
But yeah, Sleeper's numbers may not be 100% accurate, the idea is solid.
11-28-2006, 07:43 PM
#35
1st Gear Member
Join Date: Sep 2006
Location: San Angelo,TX fighting polygamy since 4/4/08
Posts: 78
RE: Power loss with 20's? here we go again!
ORIGINAL: CrazyAl
Hah! I love this! Just as much fun as thermo lab!
I think it would probably be best to model a rim as about 1/3 a flat disc (representing the "spoke" area) and a hollow ring of the remaining 2/3 of the weight, for the tubular section where the tire actually sits.
But yeah, Sleeper's numbers may not be 100% accurate, the idea is solid.
Hah! I love this! Just as much fun as thermo lab!
I think it would probably be best to model a rim as about 1/3 a flat disc (representing the "spoke" area) and a hollow ring of the remaining 2/3 of the weight, for the tubular section where the tire actually sits.
But yeah, Sleeper's numbers may not be 100% accurate, the idea is solid.
Fun isn't it
If you consider two rims of the same build and tires of the same build (just different sidewall lengths) You could probably, get away with building something that represents each rim/tire setup from about inch 16 to inch 21. It should get you the difference between the two.
11-28-2006, 08:02 PM
#37
1st Gear Member
Join Date: Sep 2006
Location: San Angelo,TX fighting polygamy since 4/4/08
Posts: 78
RE: Power loss with 20's? here we go again!
If I had an Identical set of 17s to my 20s, I would try it just for grins. I am sure mine are heavy because they where put on by the dealer before I got the car. I don't think a dyno of my car would yield the same loss as yours. Mine is a V6 (I drive a lot, 35k+ mile/year) so the powertrain only turns one wheel. lol
11-28-2006, 08:02 PM
#38
2nd Gear Member
Join Date: Jul 2006
Location: Arkansas
Posts: 202
RE: Power loss with 20's? here we go again!
I changed from 18" fanblades to 20" wheels with nearly stock size tires (I don't remember the size, and the car is not with me). Anyway my arm scale nor my buttdyno could tell a noticeable difference. However, my eye-attention meter could tell a big difference. I can't go anywhere without people starring at the car.
11-28-2006, 08:07 PM
#39
3rd Gear Member
Join Date: May 2006
Location: Palmer, Alaska
Posts: 954
RE: Power loss with 20's? here we go again!
lol! [8D]
Sleeper05 IS 100% correct in theory and logic (though I will stand by that the numbers are fuzzy lol) and ok I confess I drastically skewed his formula to chum but the fishing wasn't good!
I will also say this is about the best thread I have seen on this forum when discussing the real amount of ‘performance’ putting on a set of 20’s costs and honestly how it’ll affect our cars.
It’s weight, weight, weight, and as Sleeper05 added when that weight is mover further out on rotating mass it even more critical!
Honestly to me more then the needed HP to accelerate this mass it’s the lack of braking force that rears its ugly head…..
Btw Please don’t feel I’m switching sides, it’s just the first time on this forum I have seen the true reasons explained why most ASSUME 20’s cause performance loss. Heavy wheels and or tires (as androdz pointed out) causes performance loss!
It’s all good!
05SDI
Sleeper05 IS 100% correct in theory and logic (though I will stand by that the numbers are fuzzy lol) and ok I confess I drastically skewed his formula to chum but the fishing wasn't good!
I will also say this is about the best thread I have seen on this forum when discussing the real amount of ‘performance’ putting on a set of 20’s costs and honestly how it’ll affect our cars.
It’s weight, weight, weight, and as Sleeper05 added when that weight is mover further out on rotating mass it even more critical!
Honestly to me more then the needed HP to accelerate this mass it’s the lack of braking force that rears its ugly head…..
Btw Please don’t feel I’m switching sides, it’s just the first time on this forum I have seen the true reasons explained why most ASSUME 20’s cause performance loss. Heavy wheels and or tires (as androdz pointed out) causes performance loss!
It’s all good!
05SDI
