Ok, I have the stock 17" wheels which according to the Ford Racing website weight 25 pounds. I am trying to decide between 18" and 20" wheels. I like the 20's because of the look but worry that the ones I want weight 30 pounds. I like the 18's because they are still good looking and weight 27 pounds. I don't want to get the 18's only to wish that I had gone all the way to 20's. So my question is what is the power loss between the stock wheels compared to both the 18's and the 20's. Has anyone gone through this and felt any considerable loss in power? Is there any way to figure it out?

 

My estimate is that you would effectively add 50lbs of cargo for every 1lb heavier the wheels are and another 50lbs for every inch larger in diameter. So, a 30lb 20" wheel would perform as if you added 400lbs. That's probably a conservatively large estimate.

 

I'd say go with the 18s! Here's why:

1) They're lighter than 20s (Though the net difference is fairly small, after all, a 20" tire is lighter than an 18" tire)

2) They give you plenty of room for big brakes, if you are considering that upgrade; 20" is overkill.

3) A 20" wheel gives you a shorter sidewall which means a rougher ride and less traction off the line than the 18" (This is why the serious race guys switch to 16" or even 15" wheels in the rear)

4) Just my opinion, but 20" looks too "bling". This is a muscle car, not a "pimped out" Escalade or H2.

 

Some thing to consider is that as you increase the size of the rim you will have to decrease the size of the tire sidewall to maintain the same overall tire diameter. Maybe this decrease in height sidewall may offset the weight increase of the rim.

 

I was thinking the same thing. Does anyone know where I can get a chart that has the tire weight. I will most likely put on some BFG KDW 255/45/18 or 245/40/20. I believe someone had a chart of the BFG's info a while back.

 

you do offset it a little with the smaller tire, but do expect some power loss due to weight-- i went from stock to 20's and loss of pwr is barely noticable and im pretty maticulous

 

How is the ride quality? Is your car lowered?

 

I have 235/45 R17 tires, waaaayyyy rougher ride than 235/60 R17 but, I can whip around corners and ramps without blinking, and if I start to lose a touch of traction in the rear, I just modulate the throttle.

Less sidewall = greater handling, rougher ride

 

Agreed.

Tire weights can be gotten off of the tire rack website.

 

Ok, so I have been checking a few different brands of tires. I have checked the weight on 17's to 20's. They all seem to stay around 28-29 pounds. So there isn't any savings of weight in the different side walls.