Howdy gang! I have been feverishly researching new wheels and tires for my ride ever since installing SPC upper front control arms and springs. Right now, I have 15x8s steel wheels with 245/60/15 Cooper Cobras in the front and 275/60/15 BFG Radial T/As in the back. I love the big sidewall old school look, but lets face it, the grip sucks, the wheels are old, dated, and heavy, and well, I am kind of on this pro-touring kick right now lol. After all of my research however, I am more confused than ever! Just when I think I have decided on a combo, I completely change my mind. I'd say the first decision is whether or not to run 17s or 18s. I am leaning towards 18s for looks and performance, but 17s for cost and practicality. Our roads are terrible here in Wichta Falls, which worries me a bit. Which size do you guys prefer, and why? After cracking that nut, tire size is the next issue. I was pretty sold on throwing the fattest and tallest tire I could in the back on a 9.5" rim, but after reading a lot about actual handling characteristics, it seems that the best way to go is to have a 'square' set of tires, meaning, the same size all around as opposed to a large stagger between front and rear. Apparently it really effects the balance between under and oversteer in the turn, and large stagger can lead to the car push through the turn. Obviously, the large stagger looks way cool, but maybe a compromise would be ok? Here are my initial thoughts: 245/45/17 front - 275/40/17 rear: Same diameter tire front to back, with only 30mm stagger in width... should be a solid performer, but not very visually stunning. More stagger could be had with a larger rear tire. 225/50/17 front - 275/50/17 rear: 50 mm stagger in width and 2" in diameter. Probably not the best performer, but lots lots of sidewall and stagger for the visual pop. (I really dig the sidewall!, but is 50% apect ratio too tall for performance driving?) 245/40/18 front - 275/40/18: seems like a pretty common 18" setup, and similar to the first 17" combo I listed. More stagger could be had a larger rear tire. 255/45/17 or 255/40/18 all around. A true square setup like this as I understand promotes the best handling. Biggest concern is will the front tire fit without rubbing? Is an 8" rim the way to go all around for this or wider? For the tire make and model, I will probably go with the Nitto 555. I don't think they make a 255/40/18 so I might have to shop around there. This is a street car, so I don't need a track compound! Any other favorite tires you guys are using? For wheel make and model, I really like the Centerline Lazer II, Summit Series 143 Torque Spokes, and the Coy's C-67. I am also considering the US Mag Bandit U109 or just a black or grey 5 spoke. I'd like a sweet mesh wheel from on of the forged wheel companies, but not for the kind of money they want for them! What do you guys think? I hope this thread generates some discussion on topics like handling and stagger, not just "run this its the best because its what I have/looks the best." Thanks!! R
I always run the biggest tires I can fit. I recently put new wheels on my 71 Skylark too. I also spend time researching tire price and availability before buying wheels. 18's look better than 17 but 17s are so much cheaper. I did 275/40/18 on the front with 9.5" wheels and 295/40/18 on back with 11" wheels. I do very careful research on offsets too, mine are all -5mm offset which barely rubs the tire on the wheel well trim on the right rear and the top center inner fender bolt on the front on big bumps so 0 offset would be closer to ideal I think on these rim sizes. I also went very unconventional on wheels. I bought adapter spacers to convert the bolt pattern from 5 x 4.75 to 5 x 4.5 which opened up wheel choice immensely. The spacers are 25mm thick so wheel offset is actually + 20-25. I can guarantee no other Buick runs the same setup and I like that. The only advantage to square for me is tire rotations and spare tire matching. If I want more or less oversteer adjust suspension accordingly
Wow your setup sounds awesome. I also found the thread talking about running a 9.5" rin the front. I am concerned about my spc drop springs and stock sway bar causing issues. Where are the pics?
I'm not sure what you're using/planning to use for brakes, but keep that in mind when you pick out wheels. I'm running 17" black torq thrust m's right now and I love the way they look. However, most of the brake kits I'd like to swap into wont fit inside the barrel (spoke clearance issues) of these wheels. Now I'm stuck deciding between getting the brakes I want and changing wheels, or compromising on the brakes. If you're not upping the brake size any, then any of your choices would work fine. I have found that the 17" tires are much cheaper than the 18" equivalents. Also make sure you keep an eye on the backspacing of the wheels you choose. That one measurement can make a huge difference in both appearance and performance of your setup.
On my 70 GS I am running 18x9.5 wheels on the rear with Nitto 555 tires size 295/45/18. This is a big tire, but it has a decent size sidewall, which I like. I don't like the rubber band look (and ride quality) of the shorter sidewall 30s and 35s most folks run. The tires come real close to the upper rear inside fender lip, and I am sure it would rub in some situations. The car is not on the road yet, but if they do rub I will give them another 1/4" or so clearance on the inside lip.
My '68 has 18x9s all the way around. I have a 265/40 in front and 275/40 in back. As for wheel diameter, I'd personally go 18s, as the tire industry seems to be making that more of the default size for performance tires and many sizes are becoming hard to come by on 17s. This is all driven by OEM wheel sizes on performance cars. As for stagger, since you have the SPC arms which should correct geometry and help reduce the A Body tendency to understeer badly, I'd suggest at least some stagger. We're putting a lot of power through a solid rear axle with a so/so chassis design, so while you may read a lot about staggers causing weird handling habits, take it from my experience - you're going to want the extra grip out back. Assuming you can get the front end sorted out and gripping, these cars go from the factory designed understeer to serious oversteer. As such, put some extra tire out back, at least more than a 255 if you can. I'd go more than 275 on mine but my wheel size limited it. You can see pics on the last page of the "Lets see some pics" thread in the pro touring section. Hope this helps. Jon
Awesome, thanks for the input and clarification. Jon your car is absolutely gorgeous by the way! That is the direction I think I am leaning towards for my car. How did you adapt the bolt pattern? I will definitely go with at least 275 in the back, maybe 285 or 295. I am still thinking about the fronts. I'd really like to cram a 255 in front, but a 245 is probably more realistic, as I want to continue to run the stock swaybar (for now at least!). The tires i have now rub slightly when turning, especially when backing up, and I really want to avoid as much of that as possible. For what it's worth, I did have an epiphany: All of the front tire combinations are slightly smaller (though some up to 1" smaller) in diameter than what I have on there now, surprisingly enough. For whatever reason I kept thinking bigger wheel = bigger overall wheel+tire diameter. That will only help with the rubbing, but the wider wheel and footprint must cause their own problems right? I am really digging these wheels, especially for the price, and want something different! (yeah I know they are four-letter-word wheels, but I like them minus the spinners!): http://www.visionwheel.com/wheel.cfm?id=14894 18x8.5 +10mm Offset (4.64" bs) front 18x9.5 +18mm Offset (5.46" bs) rear or http://www.coyswheel.com/coys-c67.html 18x8 4.75" bs front 18x9 5.5" bs rear
Don't worry about ride quality when switching to low profile tires. The springs and dampers do "all" the difference. Tramlining and noise is what you get with sportier tire combos. I have tried tons of different combos on several cars and the only time the cars get significantly less comfortable is when I change springs and/or dampers. There is one myth killed for ya If you want low unsprung weight you should keep the 15 inch wheels. Bigger is always heavier. I have 275/40-20 rear tires on 20x10 (0 offset) inch wheels and they weigh in at 29 kilograms!!! 64 lbs that is. No rubbing, except for when cornering hard the tires rub on the inside. But that is probably due to old bushes. Slightly oversized fronts, 245/45-18 on 8x18 (0 offset), rubs when I drive around parking lots (low speed, no issue really). The car is dropped 3" in front though ... 20s rear look awesome, the 68-69 Skylarks heavy hips need lots of tires and wheels to lighten up visually.
Nice car Fredrik. Ryall, I used a set of custom T6061 billet aluminum adapters to get the BMW BBS wheels on my hubs. I got them from a company called Motorsport Technology out of Nevada. They can adapt any wheel stud spacing and hub bore you want, so the sky is really the limit there as long as you can get an adapter width that ends up giving you the backspacing you want. The BMW wheels I have had a 5.75" backspacing, so after the adapters, which I ordered at .75", I've got 5" all the way around. They're roughly $60 a piece. I like those wheels you pictured. I run a set of off brand wheels on my daily driver and have never had an issue, but many complain about them. As for fit, remember that the larger inside diameter can allow you to clear some suspension parts that otherwise would hit on, say, a 15x9" wheel. I have a 1" drop at the moment and can go full lock with no rubbing with the 265/40/18s in the front of my '68 with a stock sway bar. I could likely have gone even 275 or 285 in front after having looked at it. I'm not sure how the 70-72s fit though. Also, these sites may be of help, especially the first, as it will overlay the position of your current versus planned wheel and tire setup in your wheel well. http://www.tire-size-calculator.info/ http://www.rimsntires.com/specspro.jsp
I have 275 50 17 rear on 17x9.5 w/6.5 bs, front 225 50 17 17x7 w/4 bs on TT2's. You can see my pic in the "lets see some pics" thread.
For the price I seen on these, and the classic look, I do not see what the question is? Go for it and post pics.....
I am really close to pulling the trigger on those rims! I did realize that I goofed calculating the backspacing they offer!!! Here is what they have: 18 x 8.5: 4.01" / 5.14" / 5.54" / 6.01" 18 x 9.5: 5.25" / 5.72" / 5.96" / 6.75" I want to sanity check my backspacing requirements, because I have read A LOT of threads. Some made sense and concur with each other, and others are contradictory (not all on V8 Buick either). From what I understand (please correct me if wrong!) 0 offset works on the back. So, 5.25" backspace for a 9.5" wheel, or 5.5 for a 10" right? Which means the 18x9.5 with 5.25" bs should work no problem. The front confuses me a bit. Does the same zero offset rule apply to the front? If so, then there is not a wheel listed above that would fit, unless I chose the 5.14 and used a spacer (I have 1/4 spacers on there now, but would like to not have to use any). Or, is there a different requirement for the front? The Coy's come in 4.75 and 5.5, which have more than 0 offset. The other wheel I am looking at is the Centerline Laser II. They are twice as much, but you can get any backspacing you want, and they are from a well known company. They look wicked as well! I am just really attracted to the Visions since they are unique and priced well! I really don't want to mess with a spacer. For tires I have two sets picked out to choose from: BFG Sport Comp-2 sized 255/40/18 and 275/40/18. These will be a little bit more similar in size and sidewall, but the rear is smaller than I really want. or Nitto 555 sized 245/40/18 and 285/40/18 This has the big rear tire I want, but I am concerned the sidewalls will look odd with one being 114mm and the other 98 mm. Why must the tires I want always be in some obscure odd size, and why my each manufacturer size their all differently lol!? HotWired: I do really like the setup you have. It is kind of a compromise between old school and modern.
I think I have settled on the Vision wheels, 18x8.5 +10mm offset front (5.14" backspace) and 18x9.5 0 offset rear. I am still wishy washy about the back space on the front, but if guys are running 9.5" wide wheels on the front with approx 5.5" backspace then I imagine these should work fine. I will go with the BFG Sport Comp 2s with 255/40 and 275/40 out back. Any last rebuttals before I pull the triggers?
Yep - the heaviest wheel/tire combination in my corral is on the Taurus SHO. They are aluminum 20" with 245R45Z rubber and they easily outweigh everything else. My unscientific testing (back strain meter) says 50 percent heavier than the 17" steelies on my truck.
I agree that lowest unsprung weight is desirable, but based on what I have seen looking up wheel weights, the steel 15" wheels are comperable in weight to the average aluminum 18" wheel. Of course when you get to 20s, that is a lot of weight. With the 15" wheel you then have to think about all that tire weight added to it, which I would think weighs more than a tire of the same outer diameter, but sized for an 18" wheel. Then if you think about all of that additional tire weight near the outside of the wheel, that puts the rotational center of mass further out, which increases the rotational inertia. Id really like to weigh everything when the new stuff shows up to prove/disprove my theory. I can also calculate the rotational inertia as well.
I am considering going 18s on the wagon. I already have the tires. The 235/40-18 Eagle F-1s take off from my 13 Focus ST. They are summer only tires. Being that the wagon isn't driven in the winter should be perfect. I haven't decided whether or not to go the 18s ( Summit legends) or rehoop my Motorwheel spyders to 15s and run as wide as I can find speed rated. Tim
What is on the wagon now? I assume you mean 15" wide right? I would think that if you are wanting to increase performance, increasing the width of tires on the Motowheels would produce diminishing returns as the sidewall height increases. Throw those 18s on the wagon and drop it a few inches and show us the new hotness!
