anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75 bs

I'm looking for a max rubber combo without serious modifications. I have seen these sizes recommended in other posts, but would like to know if anyone is actually running them.

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

Sorry I can't personally help, but
That's the set-up I'm interested in running on my 71 lark, (315-35-17x11 w/ 6.25 bs o275-40-17x9.5 w/ 5.50/5.75 bs) I've read that several guys on this forum run that set-up w/o any mods...
BUT,
MY biggest issue is;
i can't find wheels in those sizes.
i REALLY like the Rocket Racing Hyper Shot Booster wheels, but I only see em offered in 17x8.
I also looked at the Ridler 695's (gray w/polished lip) but I'm still only seeing 17x8's...(I am seeing 18x9.5 but no 18x11, but really wanna stick w/17's.... if possible.
Do ya have to special order wheels???
I apologize for jacking your thread but, who the heck carries 17" wheels in 9.5" and 11"?
thanks

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

http://www.newstalgiawheel.com/shop/product/billet-buick

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

Thanks for the link,
but, As sharp as those wheels are,
I was looking for something with a little more of an aftermarket appearance.
i checked into some Foose wheels,
they have the "coupe" wheel in black, they are my favorite,
but they're ridiculously priced and,
of course,
no 17x11's (they do offer 17x10's though) and no 17x9.5 either (but they do offer 17x9)
close...

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

I have 15x8 with 4.5 BS wrapped in 295/50-15 and they are very close to the outer lip. Have not touched, but so close.

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

plenty of people on various forums run that size
its hard to find a 17x11 in that BS unless its a 2 piece rim usually 400-600 bucks a piece ..3 piece rims are $$$

heres one rim manufacture that offer up to 17x11 with any BS you need..
http://www.vintagewheelworks.com/products/wheels

another
http://www.billetspecialties.com/wheels/
more specificly legend series Rival rims only $310 for 17x11
Theires others but i'd have to regoogle

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

Plenty of companies do, pretty much none are carried by jegs or summit..
i think AR500? have these sizes and are carried via summit

you can also send a rim..like rocket to get widened

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

close pretty much due to sidewall bulge
low profiles you can most likely fit a 335-35-17 on 17x11...but that tire really needs a 12in wide rim, which results in notching the frame 1inch..
so ideal combo is 315s on 17x11, 18 and up are usualy 305 on 10in wide

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

Wheel visualizer
http://www.billetspecialties.com/store/wheel-visualizer/

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

Thanks Mike!
youre a wealth of knowledge, in all my lurking and thread reading/searching, you always seem to have the answers.
i also thought about contacting wheel comp.'s to see about a particular style of wheel in wider and specific backspacing,
not sure what the cost increase would be but I'll check around Monday and find out.

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

Contacting actual wheel manufacture may not be bad idea

Here's two specific wheel companies that will widen any wheel
http://www.ericvaughnmachine.com/

http://www.weldcraftwheels.com/

http://www.wheelsamerica.com/
prob run about 200-300 per wheel plus shipping each way
current backspace and width does have an effect on end results
with these prices you might as well buy correct ones if you have yet to purchase any wheels though
..just seems like a better option for someone that already has rims and dont want to rebuy.

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

I'm looking at these Centerline wheels.
http://centerlinewheels.com/wheel_deals_detail.php?id=13145&type=bolt&data=5-4.75
They have several different styles of their competition series forged rims in the 17x11 and 17x9.5. The web page only specifies .5 inch increments on the backspace, but when I called them the guy told me they could do .25's. He quoted me like 385 for the rear and 340 for the front. Said they would take 3 weeks. Billet Specialties has several rims that can be had in these sizes for about the same money.

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

I just upgraded to a 275/35/18 BFG Rival on an 9" rim for my fronts, and a 315/30/18 BFG Rival on a 11" rim on the rear. I don't recall the backspacing right now, but it will be critical. These tires may run a bit wider than other brands. The Nitto NT-05s I had earlier run a bit smaller than most brands.
On the front, I have a modified Detroit Speed 3 piece splined sway bar (I've bought entire cars for less than this bar costs!). The arms on this style sway bar allow for more clearance on the inside. The bar itself was modified to move the arms inward to allow even more tire clearance on the inside. The tires still rub the arms at full steering lock. I could have used a 1/4" less backspace. I am running a lot of caster, and the tires are within an 1/8" of hitting the rear of the inner fender well at full lock. It is a tight squeeze up there!
On the rear, I have trimmed the flange of the outer 1/4 panel lip, along with the chrome wheel well trim. It is trimmed along the top of the arc, so you cannot tell unless you lay on the ground and look up. Also, I have taken a 2 pound mini sledge hammer to the inner fender wells. I have laid them back to be even with the framerail. I ordered rims with a bit more backspace than my measuring indicated, and use various thickness wheel spacers to get the tire centered up just right. They will rub a tiny bit on the frame rail, and on the inner surface of the quarter panel about an 1" above the top of the wheel opening, but only during autocrossing. It is a tight squeeze back there too!

If I had to do it over, I would use a 9.5" or 10" wide front wheel for the 275 wide tire.
I talked to many wheel manufacturers in the "reasonable" price range, and almost none make the widths you and I are into (and have a 5 on 4 3/4" bolt pattern). If you wanted an 8" front and 10" rear, there are tons out there.
Pics of your car I have seen in the past show it to be a more modern car as far as stance and wheel/tires. The Centerline wheel is a kinda a mix between a classic wheel design and a modern wheel design. Billet Specialties makes one just like it.
Live dangerously and entertain a really modern wheel, you will blow everyone's mind!:Brow:

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

Jeff I wish I was still in Jackson to pick your brain. Will you be at the Nats this year?

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

I plan on being there (putting a whopping on the autocross course, running 11s on the drag strip, and driving back and forth from the hotel to the track with the A/C on!).

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

So what is your 'final' backspacing and/or offset including the spacers, using these widths of wheels to get it to center up? I bought a set of 18x11 and 18x9.5 wheels for my Skylark, but don't get to test fit them until October (overseas right now). I couldn't find anyone running this size so I kinda took a gamble but have the option to use different spacers to get it just right.

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

My goal was to run a 275/40r18. At the shop where my car is at we just did testing with a wheel-rite tool and with my set up of GW arms and 2" drop spindles we can not run a 9.5 wheel with a 5.5 backspace. The tool hits the upper global west arm at 90% full lock. So we went with 5" back space and it just touches the arm at full lock. We will add steering stops to correct.

As for the tire we set the tool at 275/40r18 in the font but the tool is hitting the back of the inner fender ( not just a rub but will not rotate past point of impact by a good 5/8"), and the 18" tire will hit the upper wheel inner fender bolt area under suspension travel, not just the bolt but actual inner fender lip.

Results after testing, we could go with a 255/40r18 on a 18x9 with 5" bs but that was close every where or drop down in wheel size to a 17". This would give back the ability to run the 275/40.

I see a number of guys running 17x9.5 rims and I am not sure why I can not get those to clear, Maybe because my global west arms are old, not sure if newer ones have a redesign to run the bigger wheel, also we just added a 2" drop spindle to clear the upper ball joint issue.

I think my easiest path is running a 275/40r17 on a 17x9 w/5" bs. Now to figure out the back. We might consider running a 19" rear.

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

Andy,
I have my wheels off preparing for the GS Nats, and measured the backspace.
My front 9" wheels have 5 3/4" backspace, and I am using an 1/8" spacer. The tires rub the sway bar arms at full steering lock. If you autocross, you will be at full steering lock! A 1/4" spacer would be better, but I am trying to keep my scrub radius to a minimum. I have a Detroit Speed splined front sway bar that is modified to move the arms inward. This is the main reason I can run that much back space. With a stock type tubular front sway bar, I would say 5 1/4" backspace is the max. I have some wiggle room at the fender lip, so if I had 9.5" or 10" wide wheels with the same backspace as my current wheels, it would be awesome.
On the rear, my 11" wheels have 6 3/4" backspace. I am running 7/16" spacers. My mods for this wheel to fit were mentioned in my early post.
That's all you can fit in a lightly modified GS folks!!!
Rich,
May I suggest changing to a 35 series front tire? The 40 series you are planning around is taller than optimum. This is a contributing factor with your mockup tire hitting the fender well at the top, and at the back. You may pick up a half inch of clearance, which would probably solve your problems. Also, check your caster. You may have too much if your suspension is just loosely assembled. On this note, some aftermarket A-arms move the ball joints fore and aft, so you can run more caster without the tire hitting the back of fender. You want to run tons of caster for performance handling, and what are experiencing is a common interference.
Back to tire and rim sizes. Allow me to soap box for a moment. :Smarty: Rim diameters............
A major automotive magazine (Car and Driver, I think) did a handling test using the same car and the same tire (brand and type) on the same day, but different rim diameters. As rim diameters increased, handling improved. But............... only to a point. There was a tipping point where handling decreased as the rim diameter increased further. As they got into "drug dealer" diameters, things got worse fast. Guess where the magic point was? 18" Why? As diameters increased, the weight of the wheel/tire combo increased. Increasing unsprung mass hurts handling, as most know. Also, a certain amount of sidewall flex is good, allowing the tire to conform to irregularities in the road surface. Those "rubber band" tire just don't handle!
Also, larger diameter wheels allow for larger brakes. But brakes that are needlessly large also increase weight needlessly. So, what diameter of rotors is the sweet spot? 13" to 14" is all that is needed. And guess what, they will fit in an 18" wheel. Cool, huh?
Ok, how about some further evidence? There is a new tire for absolute maximum summer performance, and it has only been out about a year. It is marketed to serious people competing in autocross and track day events that require a 200 minimum treadwear. It is the BFG Rival, and they are pretty expensive. Go to their website and see what sizes are available. Mainly 18". There are only token sizes in other diameters. Also note that there are no 40 series tires over 245 mm widths. They are just too tall for performance.

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

on a side note.
I you really want to run some wide tires up front, theirs a new FSB that's coming out that's even better then the splined detroit speed bar Jeff and I have..but it will require Speedtechs ATS/AFX spindles

Jeff, quistion for you

What do you think it'd take to fit a 295 series mounted on a 10 wide rim upfront

 

Re: anybody running this combo: 315-35-17x11 w/ 6.25 bs, 275-40-17x9.5 w/ 5.50/5.75

Thanks for the feedback Jeff. I'll have the shop set up the wheel rite tool to run 265/35r18 on a 18x9 with 5"bs and see how well we make out with figment