SGOGT4

Assuming that I can put the 16" 86 turbo wheels on my 86 na... is it correct for the factory equipment to have different sidewall heights between the front and back. I understand width is different, but tirerack tells me that factory fronts are 205/55-16 and rears are 225/50-16...

thanks

Thaddeus

Take a look at the "Watercooler" web site, they have wheel offset info posted there... http://www.cantonia.com/watercooler.html

I have no idea if it's accurate, they have a disclaimer there so I disclaim it too. But I have no reason to think it isn't accurate.

~cheers~

Thaddeus

adrial

I believe that the sidewall height number is not a hard numbers number, that it varies with the width of the tire. Possibly in a ratio er something, I really dont remember. What I do remember is going to a CART race and walking through the pit area...I looked at the size on a tire and the width was in the 300's, height in the 40's or 50's, but the sidewall was pretty high though. That's where I started to wonder about the sidewall height numbers.
My '89 951 has 245/45-16 in back and 225/50-16 up front, so yep...it's correct (the '88 951S and '89 951 have different wheels/tires than the '86-'88 951).

As far as offsets (to see if wheels fit), check the watercooler with the link that Thaddeus gave.

rangelica

In '86 the 944NA had 7Jx15 215/60VR 15 on the front and rear as standard.

The '86 951 has 7J x 16 205/55 VR16 front and 8J x16 225/50VR 16 on rear.

Rick

'86 951

Greg Hammond

In a tire size like 225/50R-16, the "225" is the width of the tire in millimeters, the "50" is the % ratio of the sidewall height to tread width. So, your true sidewall heights are:

225 * 0.50 = 112.5mm for the backs
205 * 0.55 = 112.75mm for the fronts

The 0.25mm height difference isn't noticible when looking at the car, but yes - the heights are indeed "different".

Keep in mind, the width number isn't a hard-fast rule in determining true tire width. Some manufacturers/brands of 225 wide tires might be the same as another manufacturer's 215 or 235 wide tire. Go figure.

Greg

Olli Snellman

in 1986 several tire/wheel combinations were available.The entry level was 185/70-VR15 front & rear.The wheel offset was 23.3 mm.
Second option was 215/60-VR15 front & rear with wheel offset 23.3mm.The third option was 205/55-VR16, wheel offset 23.3mm front & rear.The fourth option was so called sport pacakge with 215/60-VR15 with wheel offset 23.3mm rear & 10.6mm front.
All wheel were 7 j x 15 or 7 j x 16 expect the sport pakcage has 8 j x 15 rear wheel.
1986 Turbo has 205/55-VR16 front tiers & 225/50-VR16 rear tiers.The wheel size was 7 j x 16 front & 8 j x 16 rear.The offsets were 10.6 front & 23.3mm rear.

Olli
'88 Turbo

Dave

Olli, Best info I can find suggests that US cars were only available with 15" wheels with 215/60-15, or 16x7&8 with 205/55-16 & 225/50-16 from the factory. It seems that there are always fewer options here then on cars built for other parts of the world.

Danno

NO, NO, NO. Don't fall for the incorrect info found in the 944FAQ. There has been numerous errors in measurements or calculations that resulted in these mistakes in the 944FAQ. ALL pre-'87 cars had 23.3mm offset in all sizes and options. Simple.

I made a new 944WheelsFAQ on my website and shows you how to correctly measure and calculate wheel sizes and offsets: http://members.rennlist.org/951_racerx