bigger tires on 17" OEM wheels ??

[cnatra]

Anyone try putting bigger tires on the 17" offroad wheels ??

I noticed 305/55/20's at the dealer so i'm thinking that width must be OK

SO now i'm wondring if a set of 305/70/17's will clear or be to tall ???


It's good to know the Daystar lift makes a difference though,
those 325/60/18's on billqaudiovideo's 4x4 LE CC look awesome!

[gsxr1000]

I'm getting 20's for my LE whats the biggest size tire I can put on there with the daystar 2.5 front end lift 305/55/20????

[Doghouse]

305*.55=167.75
167.75/25=6.71
6.71+6.71+20 = Tire height of 33.42

305*.70= 213.5
213.5/25 = 8.54
8.54+8.54+17 = Tire height of 34.08

You are talking 2/3 of an inch higher. This will put the spedo a little out of calibration, but "I Doubt" it would rub. I would be more concerned about the fact that you are putting too wide of a tire on the stock rim. I beleive it is a 7.5 or 8 inch rim. for a 12" wide tire, you want a 10 inch rim. You may have to adjust the turn stops a little. I would make sure you could cancel the deal if there was a rubbing issue.

[tortuga]

it'll put the speedo off by about 7.5 mph.

when your speedo reads 60mph, you're actually travelling 67.5mph

big difference!

it would rub because the diameter is much bigger, but the increase in width being so minimal would not be the cause of rub.

[Doghouse]

Going from a 285 to a 305 is .8" in width, it is almost the same as the change in height (.8 vs .66 inches)

[Dobb]

Prometheus,
By going from a 285/70/R17 tire to a 305/70/R17 tire will only put the speedo off 3.4%. So, when your speedo reads 70MPH you are actually going 72.4 MPH with the bigger tires. Not that big of a difference. I didn't want your 7.5MPH difference to scare cnatra.

[cnatra]

Originally Posted by Dobb

Prometheus,
By going from a 285/70/R17 tire to a 305/70/R17 tire will only put the speedo off 3.4%. So, when your speedo reads 70MPH you are actually going 72.4 MPH with the bigger tires. Not that big of a difference. I didn't want your 7.5MPH difference to scare cnatra.

yeah, I thought that was a little high

I just went to google & checked out the various tire size calculators

3.3% -3.4% looks about right , I just need to find out if these will clear

I plan on installing the Daystar lift kit so it may be a moot question

[CaliforniaTitan]

I use this calculator to figure mine out:

http://350zx.com/tire-wheel.html

Chris

[gsxr1000]

So you think the 305's will rub even with the 2.5 inch daystar lift????

Originally Posted by CaliforniaTitan

I use this calculator to figure mine out:

http://350zx.com/tire-wheel.html

Chris

[CaliforniaTitan]

What doghouse said...

I would be more concerned with rubbing as your going to a wider tire (Not at the top of the tire, but on the backside of the tire against the suspension) and also that the tire is 12" vice the 8" on the current. It is really going to depend on what 20" wheels your planning on using. You can't think of it just as tire size...but as the whole package. You have to consider offset. If you go with a lower number offset you should not rub at all.

What wheels are you looking at?

Chris

[gsxr1000]

MKW 34

http://www.mkwheel.com/mk34.asp

Originally Posted by CaliforniaTitan

What doghouse said...

I would be more concerned with rubbing as your going to a wider tire (Not at the top of the tire, but on the backside of the tire against the suspension) and also that the tire is 12" vice the 8" on the current. It is really going to depend on what 20" wheels your planning on using. You can't think of it just as tire size...but as the whole package. You have to consider offset. If you go with a lower number offset you should not rub at all.

What wheels are you looking at?

Chris

[CaliforniaTitan]

From what I see in the calculator....

Your going to hit on the inside as your coming in 1" further.

Also, at 70mph indicated..you would be doing 79mph.

To get it 'right' for the speedo you would have to go down to a 55 vice 70 series tire.

To get it out far enough not to rub you will have to put 1" adapters to push the wheels back out to stock range.

Wait...inboard would be 2.5mm less...i typed wrong in the calculator...but still I think your gonna rub...


Chris

[cnatra]

Originally Posted by cnatra

It's good to know the Daystar lift makes a difference though,
those

325/60/18's on billqaudiovideo's 4x4 LE CC look awesome!

325/60/18's apparently fit with no problem with the Daystar lift

www.titantalk.com/showthread.php?t=10293

[cnatra]

Originally Posted by CaliforniaTitan

From what I see in the calculator....

Your going to hit on the inside as your coming in 1" further.

Also, at 70mph indicated..you would be doing 79mph.

To get it 'right' for the speedo you would have to go down to a 55 vice 70 series tire.

Chris

speed difference at 75 would be +3mph, 78mph

60mph about 62mph

[gsxr1000]

I am putting the 305/55/20 on it not the 305/70/20