19" rim ?

[ashman]

Re: 19" rim ?

it's kinda hard to see it in the pics of my truck but, the wheels are actually wider than the tires. the tires have rim protectors and the protectors protrude, just slight, beyond the wheel lip but, the actual tread width is less than the wheel width.

if i were doing it again, i'd go with wider tires. maybe 275's upfront and the matching widths (315 or 335) on the rears.

 

[saint d]

Re: 19" rim ?

in order to keep the front and rear gear ratios within 1% as not to cause the center diff / viscous coupling to slip you must maintain the same tire hieght (26.5"= factory tire) when you increase the 2XX number or the tires prefix number it increases the width BUT it also increases the hieghth inadvertintly thus you must use a shorter side wall AKA the profile. the next two numbers 2xx/YY are the profile. the last two numbers just being your wheel diameter. off road guys are lucky when it comes to tires as they say the entire hieghth and contact patch. you might see a 31x10.5 which is 31" tall and has a 10.5" width from inside sidewall to outside sidewall. all this being said the first number say it be 275 is a 275mm measurement from bead to bead and has nothing to do with the actualy contact patch! the bigger the tire gets the wider and thus you use the profile of the tire to taylor the hieght of the sidewall to match an apposing set of tires in overall hieght. ok.. too much typing ...must rest ..now ...........................................................

 

[live1053rulz]

Re: 19" rim ?

in order to keep the front and rear gear ratios within 1% as not to cause the center diff / viscous coupling to slip you must maintain the same tire hieght (26.5"= factory tire) when you increase the 2XX number or the tires prefix number it increases the width BUT it also increases the hieghth inadvertintly thus you must use a shorter side wall AKA the profile. the next two numbers 2xx/YY are the profile. the last two numbers just being your wheel diameter. off road guys are lucky when it comes to tires as they say the entire hieghth and contact patch. you might see a 31x10.5 which is 31" tall and has a 10.5" width from inside sidewall to outside sidewall. all this being said the first number say it be 275 is a 275mm measurement from bead to bead and has nothing to do with the actualy contact patch! the bigger the tire gets the wider and thus you use the profile of the tire to taylor the hieght of the sidewall to match an apposing set of tires in overall hieght. ok.. too much typing ...must rest ..now ...........................................................

Sorry to be the bearer of bad news, but some things you said were incorrect:
That 2XX number can also be a 1XX or 3XX in many cases.
The AKA "profile" is also incorrect, it's refered to as the "aspect ratio" in the industry.
The width most definitely has to do with the contact patch, it (and the tread style along with tire pressure) are essentially the only things that have to do with your contact patch. The measurment from bead to bead is directly proportional to the width and contact patch of a tire.
Also, you said in the beginning that you want to keep the overall diameter the same as from the factory (26.5"), which is not true. You want to maintain the same diameter front to rear, but there is definitely room for fudge when it comes to overall diameter at all four corners. And you don't only use an aspect ratio (or profile as you put it) to change the sidewall of your tire, you more commonly change your wheel diameter.
Any questions grasshopper?

 

[ty166]

Re: 19" rim ?

i've been looking for deals on rim/tire combos. on e-gay there is a add for chrome z06's that are 18x9.5 rim with 275/35zr18 and a 18x10.5 rim with 295/35/zr18 , do you guys think that would work out for me, i was trying to figure out where black night was coming up with tire diameters but i couldnt find it, maybe he's right and he does know everything.....lol i hear alot of people that say they wish they went wider or bigger, just trying to avoid that if possible. what is the widest tire you can put on a 10.5 inch rim anyway. thanks for all the input and help guys....

 

[live1053rulz]

Re: 19" rim ?

Nah, those won't work. Too much of a difference in overall diameter front to rear. Ain't that a &!+@#? Nothing can be easy. If only we had Corvette's.

 

[ashman]

Re: 19" rim ?

you can think of the aspect ratio as a percentage of tread width and in this case it's 35%...so

35% of 275 is 275x.35= 96.25mm (the side wall is 96.25mm high)

now to calculate tire diameter.

hole diameter = 18 inches
sidewall height = 3.78 (96.25mm/25.4mm=3.79) x2=7.59 inches

275/35/18 diameter = 25.59 inches

295/35/19 diameter = 26.12 inches

which is roughly a 2% difference in diameter but, what were really concerned with is effective radius, which is the measurment from the center of the wheel to the ground. this can be affected by tire pressue, weight on wheels, wear ...etc.

i think that's right

 

[saint d]

Re: 19" rim ?

allright I'm done. I passed the 8th grade unfortunately so I don't work at discount tire. I'm just a lonely carpenter who dables in automotive. I'm just used to offset setups because alot of people I know run wider front tires. what? wider front tires? auto crossing. wider fronts, allwheel drive, evo's and sti's !

 

[ashman]

Re: 19" rim ?

just use this....much easier

http://www.precisiongear.com/pgtechtire.htm

 

[live1053rulz]

Re: 19" rim ?

allright I'm done. I passed the 8th grade unfortunately so I don't work at discount tire. I'm just a lonely carpenter who dables in automotive. I'm just used to offset setups because alot of people I know run wider front tires. what? wider front tires? auto crossing. wider fronts, allwheel drive, evo's and sti's !

I'm not done, yet. I passed 8th grade too, and I'm in college actually. And I don't work at Discount Tire.
You're used to staggered setups you mean, not offset setups. They don't run wider front tires when they autocross in awd cars. Never. The only time you'll see that is in FWD drag racing. Please stick to building houses my friend.

 

[ty166]

Re: 19" rim ?

you can think of the aspect ratio as a percentage of tread width and in this case it's 35%...so

35% of 275 is 275x.35= 96.25mm (the side wall is 96.25mm high)

now to calculate tire diameter.

hole diameter = 18 inches
sidewall height = 3.78 (96.25mm/25.4mm=3.79) x2=7.59 inches

275/35/18 diameter = 25.59 inches

295/35/19 diameter = 26.12 inches

which is roughly a 2% difference in diameter but, what were really concerned with is effective radius, which is the measurment from the center of the wheel to the ground. this can be affected by tire pressue, weight on wheels, wear ...etc.

i think that's right

you've got to be shitzin me........ thats just way to much math to be doin.... lol , cant i just leave the front prop shaft out.....lol i guess ill just have to ditch the c-5 fronts and put the ugly stockers back on.......

no.. seriously thanks again, wealth of info here , thanks for helpin and takin the time to explain all this tire stuff...

 

[Black Knight]

Re: 19" rim ?

Hey Steven don't worry you I got your back on this stuff :tup:

Question for you though Steven. I know alot of people say you might have to grind on your control arms to get a 9.5" wide to fit, but did you notice/ or have you tried any wheels on since you got the coilover setup? Did you gain any more clearance? I wonder because I just got it and there is no way in hell I'm grinding on a $1,000 set of control arms :tdown:

 

[gjp]

Re: 19" rim ?

Ouch, relax guys.
1st off I have been to Stevens shop. Very nice setup. In fact I hope to have a syty meet there. I have talked to Steven and he knows his $hit for a young kid.
and I have a AA degree(dont know how) and I am just a construction worker. (whatever that is worth?? so there )

 

[James Thomas]

Re: 19" rim ?

Auhuummm...... back to the subject, here is what I base my fitment info on:

http://www.bfgoodrichtires.com/specs/g-force-t-a-drag-radial/1161.html

295 / 345 combo
---------Tire ------------- Rim ----------Section ------ O.L. Dia. ----- Revs Per Mile
P295/35R18/LL ----10 - 12 ------11.7 on 10 ------ 26.2 --------------- 794
P345/30R18/LL ----12 - 14 ------13.8 on 12 ------ 26.2 --------------- 794

275 / 315 combo
------- Tire -------------- Rim --------- Section ------ O.L. Dia. ------ Revs Per Mile
P275/35R18/LL ---- 9 - 11 ------ 10.9 on 9.5 ----- 25.6 --------------- 813
P315/30R18/LL --- 11 - 12 ------ 12.6 on 11 ----- 25.6 --------------- 813

As you can see, the 295 / 345 combo is the exact same overall Dia.front and rear as is the 275/ 315 setup. ZERO front to rear size difference which is X-fer case friendly .

Now we all know that the 275 / 315 is a sure thing fit. As to the 295 / 345 set up I would guess (and thats just what it is, a guess), the coil over or tubular A-arm control arms have more clearance and I base this off of not SyTy info, but every vehicle we have done suspension upgrades on from Vette's and Jags to rice and potato's so I'm not sure. I do know the tube A-arms on my 92' C/K 1500 allowed a 1.5" wider wheel tire combo. For the 18x9.5 with stock control arms, they need to be slightly spaced and the arms clearanced (on my Ty anyway). For the 18x12 & 345 combo on the rear, yes it's a cu$t hair of clearance but spaced correctly and even if I have to ever so slightly notch or just demple the frame, it will be worth it. Sorry Ash, I thought this was your truck. So... who's Sy is this with 18x12 & 345's?






Note: Edited the previous 1" drop statment as commented below :tup:
__________
James

 

[jjorgensen52]

Re: 19" rim ?

I run 9" up front on the coilovers and they're not even close :2cents:

 

[James Thomas]

Re: 19" rim ?

I run 9" up front on the coilovers and they're not even close :2cents:

Kinda thought so. How wide do you think you could go on the front so the boys have a better educated guess than I could give? I had a sure feeling that it was at least 1.5" - 2.0" but wasn't sure.

______________
James

 

[jjorgensen52]

Re: 19" rim ?

Off the top of my head I would say probably an additional half inch or so would put it as tight as I would care to run... thats a 10" front rim ... but then you start rubbing tires on stuff. I should be home this weekend and I can check

 

[live1053rulz]

Re: 19" rim ?

Haha, thanks guys. I'm just givin the guy a hard time, I'll cool it. No offense to construction or anything, just playin' with our noob. As for the 9.5 up front, I know with the stock setup you could get 'em to rub, but haven't tried anything on there so far with the coilovers. I'm just runnin' the 9's for now. However, I plan to do some test fitting for some new wheels in the near future, so I'll be sure to let you know. Also, with the coilover kit, right out of the box the steering is very limited. There are a couple ears/tabs that you'll need to grind down to give yourself more of a steering angle. I think they're meant to be that way, probably for this very reason. You'll be able to limit your steering with a stopper rather than your wheel or tire. So that should be just peachy no matter which wheel you go with.

Now off to my last final before the winter break. WooHoo!

 

[Black Knight]

Re: 19" rim ?

Auhuummm...... back to the subject, here is what I base my fitment info on:

http://www.bfgoodrichtires.com/specs/g-force-t-a-drag-radial/1161.html

295 / 345 combo
---------Tire ------------- Rim ----------Section ------ O.L. Dia. ----- Revs Per Mile
P295/35R18/LL ----10 - 12 ------11.7 on 10 ------ 26.2 --------------- 794
P345/30R18/LL ----12 - 14 ------13.8 on 12 ------ 26.2 --------------- 794

275 / 315 combo
------- Tire -------------- Rim --------- Section ------ O.L. Dia. ------ Revs Per Mile
P275/35R18/LL ---- 9 - 11 ------ 10.9 on 9.5 ----- 25.6 --------------- 813
P315/30R18/LL --- 11 - 12 ------ 12.6 on 11 ----- 25.6 --------------- 813

As you can see, the 295 / 345 combo is the exact same overall Dia.as the 275/ 315 setup, and ZERO front to rear size difference which is X-fer case friendly and gives you a built in one inch drop over the stock 26.5 tire size

James your numbers are wrong, stock tire size is 25.6" tall, your new wheel and tire combo will be a little over 1/2 a inch taller.

I'm missing something because your saying that both those combo's are the exact same size, the numbers you posted don't even say that. 25.6 and 26.2.

 

[jjorgensen52]

Re: 19" rim ?

Also, with the coilover kit, right out of the box the steering is very limited. There are a couple ears/tabs that you'll need to grind down to give yourself more of a steering angle. I think they're meant to be that way, probably for this very reason. You'll be able to limit your steering with a stopper rather than your wheel or tire. So that should be just peachy no matter which wheel you go with.

Now off to my last final before the winter break. WooHoo!

I ground the stops on my CBR kit considerably when I did the install... I don't think I've lost anything in terms of steering now over stock, but compared to the GT this thing needs a huge circle to turn in...

 

[James Thomas]

Re: 19" rim ?

James your numbers are wrong, stock tire size is 25.6" tall, your new wheel and tire combo will be a little over 1/2 a inch taller.

I'm missing something because your saying that both those combo's are the exact same size, the numbers you posted don't even say that. 25.6 and 26.2.

Well if I messed up on the stock 16" O.A. tire Dia. at 26.5, my bad and I apologize because I thought the 255/50/16's were 26.?. Also on the "exact same size" as in zero difference front to rear for each combo. I'll edit the post and clear it up a little cause My wording is screwed as usual at 2:30 in da AM. If the stock 16" O.A. is 25.6, then my 295 / 345 combo will be the same.

Thanks for pointing that out :tup: !

__________
James