[Tom Vaught]

1970 GTO
2 Inch "dropped height" springs
17 Inch rims 8" front 9" rear (Performance Years aluminum wheels)

Going for the resto-mod look

Rear tire is 255/45-17 mounted on the rear

Front Tires (recommended by PY Members)

Tires will be NITTO 555 Style Tires

Post up suggestions/ Previous Experience with similar vehicle/wheels

Tom V.

[62posbonny]

I have a 1971 Cutlass with 18x8 fronts with 245/45r18 and 18x9.5 with 275/40r18 Nitto 555g2's. These tires spec out on Nitto site as 26.65" and i wouldnt want to go any shorter to fill out the wheelwells. I initially had UMI 2" lowering springs and switched out to 1" lowering springs due to severe tire rubbing on the front when turning. I like the tires for everyday driving, they track nice and are not noisy. They are not a super sticky tire, though, and traction from a stop is very limited with my 400tq/420hp chassis dyno numbers.

[1965gp]

1970 GTO, stock (original) suspension, 17 x 9 honeycombs with 275 40 17’s all the way around

[1965gp]

1968 LeMans Hurst wheels 17 x 8 (I think). 245’s on the front, 275’s on the back

[Scarebird]

Bandit U109's - Rally II look-a-like 17"

[vertigto]

1970 GTO - Viking coilovers, BMR tubular A-arms, UMI rear shock tower brace, adjustable rear upper control arms, 4 wheel disc brakes/hydroboost, etc.

For comparison, mine has 18s:

Wheels - 18" US MAGS U111 RAMBLER (Gunmetal with Diamond Lip)
Tires - NITTO NT555 G2 (245/45R18) front and NITTO NT555 G2 (275/40ZR18) rear

[The Champ]

Tom

255/45/17's are only 26" tall - I think something closer to 27" would work better (even with a 2" drop). 255/50/17 (available in the Nitto) would get your friend there. Possibly run the 255/45/17'a on the front to provide a .5" rake.

This assumes the BS on the rims will allow those sizes. If 255/45/17 is too wide for the BS on that rim, a 225/50/17 (available in the Nitto) would be almost exactly the same height, but should solve clearance issues.

I currently run 215/55/17 (26.3")front and 245/50/17 (26.6" - tallest size in the Continental DWS 06) rear on my '64. As I understand it, the '70 GTO has more room up front that I have on my '64. Looking at those Nitto's - I'd probably do a 225/50/17 and 255/50/17 when I replace my Continentals (probably next year or 2).

The reason I went with Continental's is our grandson was working for them at the time and I was able to get them at his employee cost for the GTO and the Camaro - less than $800 for all 8 tires. He's a crew chief for a VM-22 Osprey over in Okinawa now, so no more tire discounts for me....

Photos below. The Camaro has 275/40/17 rear and 235/45/17 front. Front is dropped 2", rear 1".

[JLMounce]

1971 Chevelle. Lowered 2" at all 4 corners. American Racing Rodder wheels. 18x8 front with 245/45/18 rubber 18x9.5 rear with 275/40/18 rubber.

I really do feel like the A-body can use the larger 18" wheel and the 27" overall height tire.

[Scarebird]

not so sure about that - my 71 has 17x8's with 235-55-17 (26" high) does rub on tight turns with articulation.

[JLMounce]

Originally Posted by Scarebird

not so sure about that - my 71 has 17x8's with 235-55-17 (26" high) does rub on tight turns with articulation.

My wife's Chevelle rubbed a bit as well. Most of the off the shelf wheels in the 8" wide size are going to be a zero offset. Especially with disc brake cars and many aftermarket discs, the A body really needs the wheel set inward.

A 4.75" backspace for the front on an 8" wheel would be ideal from my experience.

The problem of course is when you start getting in to custom backspacing, the price of wheels start to go up pretty dramatically.

What I did on my wife's car was to add .9" tall ball joints which keeps the camber curve from working against you and we went on the more aggressive side at about an inch of negative static camber, while going to a hollow 1 3/4" Helwig front sway bar. All of that helped keep rubbing to a minimum when we put the car 3" down in the front. The trade-off is accelerated tire wear. The handling was greatly improved though.

[The Champ]

Originally Posted by Scarebird

not so sure about that - my 71 has 17x8's with 235-55-17 (26" high) does rub on tight turns with articulation.

Those 235/55's are 27.1" tall, plus or minus a tenth of an inch.

Backspacing would be critical on a tall tire like that.

[Verdoro 68]

17x8 on 245/45/17 in the front, 17x9 255/50/17 in the rear with a 1" UMI drop and an addition 1/2 coil cut out of the front springs.

The front tires cut it pretty close, not sure you could go wider. I could have fit a 275 on the rear no problem. These are Nitto 555s that Diamondback put redlines on.

Thread is here: https://forums.maxperformanceinc.com...ne+year&page=4

[Scarebird]

Originally Posted by The Champ

Those 235/55's are 27.1" tall, plus or minus a tenth of an inch.

27" wide, measure 26" tall (vertical with weight on vehicle), so that is where this came from.

[The Champ]

Originally Posted by Scarebird

27" wide, measure 26" tall (vertical with weight on vehicle), so that is where this came from.

They are not 27" wide. The diameter is 27" - which is how tall they are.

Actual tire measurements for the Continental DWS 06:

Sect. Width:
9.6"
Tread Width:
7.6"
Overall Diam.:
27.2"

Your 26" number is possiblly correct for a parked vehicle measurement with cold tires, but not for a car driving at highway speeds. Not only because of the speed, but as the tire heats up the pressure grows causing the tire to expand.

Watch some NHRA top fuel action and you can see tires grow....