Would getting 18" wheels negatively affect peformance?

I was wondering how many of you guys are running 18" wheels and if you noticed a big difference in acceleration/deceleration? I want to get 18x9 wheels with a 26.6 tire. If its going to affect peformance a lot I won't get them. I'm just having traction issues and wanted better launches.

Going to 18" wheels isnt going to help with traction issues, need better tires for that. I run 18x9 Cobra R's and never noticed a difference, except in handling over a stock rim and tire.

You generally want more sidewall for straight line launching, so if you are serious about that, stick with 16".


cheers
Ed

90tbirdsc said:

I was wondering how many of you guys are running 18" wheels and if you noticed a big difference in acceleration/deceleration? I want to get 18x9 wheels with a 26.6 tire. If its going to affect peformance a lot I won't get them. I'm just having traction issues and wanted better launches.

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The 18" wheels aren't going to do anything to improve performance, they are just a cosmetic mod. If you get a chrome Cobra R or Saleen Speedstar the wheels will be heavier than stock, but not enough that you could feel it when driving the car. If you want better traction when launching, just put a set of drag radials on the back.

David

Well I'm getting 18x9 wheels so I can run a wider 275 tire. I just didn't know if the extra weight would be felt or not.

What are you guys running for street tires?

90tbirdsc said:

Well I'm getting 18x9 wheels so I can run a wider 275 tire. I just didn't know if the extra weight would be felt or not.

What are you guys running for street tires?

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I'm using 245-45-18 up front and 275-40-18 on the back. Currently using some directional Hankook Ventus V12 evo, Z rated tires for the street. They are a little pricey, but I like them because unlike the Nittos I used to have, they leave nice dark marks when you spin the tires



David

You will feel the difference, especially in braking. It's not a deal breaker, and depending on how you drive or how much power you have your results will vary, but I definitely felt the difference.

David Neibert said:

I'm using 245-45-18 up front and 275-40-18 on the back. Currently using some directional Hankook Ventus V12 evo, Z rated tires for the street. They are a little pricey, but I like them because unlike the Nittos I used to have, they leave nice dark marks when you spin the tires

David

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Show off

What nitto tires did you have and how do the hankook's you have now compare?

When tires leave no marks you probably grabbing pavement more then if you leave black behind.

18s will improve cornering. Ever seen a picture of tires under heavy corners. More side wall means more flex and distortion of the tire. Low profile tires look good to boot, unless you are going for the drag look.

Wheel weight (and how far out from the hub the weight is located) will affect performance. Compare the intended combo to stock if you are concerned.

I agree, you will feel a loss of performance from even a 16 to a 17. I noticed a significant loss from 18 to 20. But....20's brah It's worth paying the $2500 to offset about $2000 worth of performance. Wow, this is a horrible hobby.

I know there is a ton of variables here but anyone have a clue how 1/4 times would change going from stock 16" to 17" or maybe 18" wheels? Just a rough guess?

ricardoa1 said:

When tires leave no marks you probably grabbing pavement more then if you leave black behind.

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I don't think so.

The Nittos I had were a harder compound and unless you were sitting there holding the brake and burning the tires in 3rd gear (which I don't do), they left very light marks on concrete, that would fade away after a week or so. Almost like spinning your tires on wet pavement. With these Hankook tires the marks stay for months.

I don't know what the Goodyear Super something tires that came on my wife's Charger SRT8 were made out of, but I did a burnout in front of our house on July 4th 2006 when we ran out of fireworks and the marks are still there. Since the car was only 3 days old, I got in a lot of trouble for that and those friggin tire marks were a constant reminder to her

See this thread for pics. http://www.sccoa.com/forums/showpost.php?p=543890&postcount=27

David

When I went to 17*8's with 255's I noticed an increase in performance. When I went crazy with my buldging rear tires 285's I noticed a loss in performance (It wiggled a bit)

Bottomline though is what type of performance are you talkig about. Handeling, braking, launching, ride quality.

If its just acceleration well it depends. If you have a basically stock car a good set of tires on your stock 16's will work. The more power you make the more tire you will need..And a 275 up front...no. Also more drag especially up front will make a difference in acceleration

David Neibert said:

I don't think so.

The Nittos I had were a harder compound and unless you were sitting there holding the brake and burning the tires in 3rd gear (which I don't do), they left very light marks on concrete, that would fade away after a week or so. Almost like spinning your tires on wet pavement. With these Hankook tires the marks stay for months.

I don't know what the Goodyear Super something tires that came on my wife's Charger SRT8 were made out of, but I did a burnout in front of our house on July 4th 2006 when we ran out of fireworks and the marks are still there. Since the car was only 3 days old, I got in a lot of trouble for that and those friggin tire marks were a constant reminder to her

See this thread for pics. http://www.sccoa.com/forums/showpost.php?p=543890&postcount=27

David

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My experience is the more the tires made noise and left tire marks, the less forward movement I experienced. The nittos leave almost no marks, dont squeal and made my car less fun = more traction. But my cars dont destroy tires so maybe you big HP are on a different playing field.

XxSlowpokexX said:

When I went to 17*8's with 255's I noticed an increase in performance. When I went crazy with my buldging rear tires 285's I noticed a loss in performance (It wiggled a bit)

Bottomline though is what type of performance are you talkig about. Handeling, braking, launching, ride quality.

If its just acceleration well it depends. If you have a basically stock car a good set of tires on your stock 16's will work. The more power you make the more tire you will need..And a 275 up front...no. Also more drag especially up front will make a difference in acceleration

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On a stock car, switching from stock tires and wheels to the popular 18x9 size with 245/45's up front and 275/40's in the rear I immediately noticed a heavier steering feel and loss of braking performance. Yes, grip was improved of course, but the brakes will now fade if pushed too hard and pedal effort is higher. Traction is improved in forward motion but more noticeably in cornering. Yes, the wider tires grip better, but the added rotating weight is also quite noticeable. Don't think you can feel the difference? Try putting your stock tires back on.

As for 1/4 mile running, the 18's do grip better, but they weigh more and slow the car down too unless you have enough power to where it doesn't matter. On a 14 second car it makes a difference. Just how much is hard to say. I know there have been tests run on Mustangs between running skinnies up front vs. street tires and some have picked up .2 sec. YRMV

Would I avoid bigger wheels and tires? No. Does the extra weight make a difference? Yes. Do they grip better? Generally speaking, yes. But if you just want to 1/4 mile, then the best thing is to put on a set of 16" drag radials or ET streets on the stock wheels and get a pair of skinnies for the front.

On a relatively stock car, 255/50/16's will grip as well as 275/40's.

What about when it rains? I noticed the 255 and 245s were very loose in the rain since lbs/square inch were less compared to the 225.

BirdofPrey97 said:

What about when it rains? I noticed the 255 and 245s were very loose in the rain since lbs/square inch were less compared to the 225.

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That has a lot more to do with tread compounds and pattern (ie. void ratio) than actual tire width. But I don't think anyone was worried about wet traction. lol

XR7 Dave said:

On a stock car, switching from stock tires and wheels to the popular 18x9 size with 245/45's up front and 275/40's in the rear I immediately noticed a heavier steering feel and loss of braking performance.

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I just want to confirm David's observations. When I installed 17" wheels on my bone stock 95, I immediately noticed a difference, especially in braking. When I took the same 17" wheels off my 92 and replaced them I didn't notice the braking as much, but the 92 also has 13" rotors which I suspect somewhat hides the issue.