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I am thinking of switching back to the original wheels for my cutlass after I get them media blasted and painted. When I bought the car I switched them out and put 15x7 Cragars on because of how low the car was sitting (I kept bottoming out on speed bumps). I know that original equipment is 215/75-14. However, all the BF Goodrich tires that I am finding are 215/70-14.
My question is this...how big a difference is there is a aspect ratio of 70 instead of the original 75? Will I be hugging the ground again? I'm not a tire guru so I really have no idea.
Aspect Ratio is sidewall height as a % of width. width is stated in millimeters Comparing a 215/75 to a 215/70 the 70 will be a little less than an inch short.
225/70's are available and fit a little better
I am thinking of switching back to the original wheels for my cutlass after I get them media blasted and painted. When I bought the car I switched them out and put 15x7 Cragars on because of how low the car was sitting (I kept bottoming out on speed bumps). I know that original equipment is 215/75-14. However, all the BF Goodrich tires that I am finding are 215/70-14.
My question is this...how big a difference is there is a aspect ratio of 70 instead of the original 75? Will I be hugging the ground again? I'm not a tire guru so I really have no idea.
Go 225/70R14. My 70S has a ridiculous amount ground clearance, especially on the front, 205/70R14 and 225/70R14 BFG TA's. My 88 has low ground clearance as well. I have 205/75R14 front and 215/75R14's on the back on the 88. It has helped compared to the 235/60R14 that were on it. Remember one size wider in a 70 series will be close to a 75 series in height. Here is a good calculator.http://tech.oldsgmail.com/axle_RPM.php
Last edited by olds 307 and 403; November 12th, 2018 at 09:46 AM.
Go 225/70R14. My 70S has a ridiculous amount ground clearance, especially on the front, 205/70R14 and 225/70R14 BFG TA's. My 88 has low ground clearance as well. I have 205/75R14 front and 215/75R14's on the back on the 88. It has helped compared to the 235/60R14 that were on it. Remember one size wider in a 70 series will be close to a 75 series in height. Here is a good calculator.http://tech.oldsgmail.com/axle_RPM.php
Thanks for the info. Two more questions.
I have the bezel rings, but do not have the center caps. I don't mind buying repros, but everything that I am finding does not have the mounting hardware included. What does the mounting hardware look like and are the SSII and SSIII center caps the same?
If the rims are original to your car they'll have bolt on caps so all you need are a handful of bolts/screws that thread in. SS1's you a retainer.
SS2 & SS3 are the same except for the paint
That tire size didn't exist when your car was new. Original equipment was F78x14 (G78x14 for cars with A/C due to the extra weight). G70x14 was optionally available.
What matters is overall tire diameter. F78x14 tires were 26.5" diameter. G78x14 were 27.02". G70x14 were 26.82".
225/70-14 tires are 26.4" diameter. 215/75-14 are 26.7" diameter. Keep in mind that radial tires have more flexible sidewalls than do the original bias ply tires. The actual ground clearance will be slightly less than the theoretical diameter would suggest because of that.
75 to 70 is not very noticeable. 60 is noticeable from a 70.
You need to do the math. 225/75-14 (if you can find them) is 27.3" OD. 225/70-14 is 26.4" OD. 225/60-14 is 26.05" OD. The difference between 75 and 70 is 0.9". The difference from 70 to 60 is 0.35".
Thanks guys. They are the original rims. They came with the cutlass when I bought it. I just never mounted them because they were all scraped up and I figured that I would wait until I had put back enough money to paint the car and then get the rims done at the same time.
Thanks guys. They are the original rims. They came with the cutlass when I bought it.
Just for grins, why don't you post a photo of one of the wheels so we all know for sure if they are bolt-in or snap-in. I suspect that most early cars now have snap-in SSII/III wheels.
Here are a few pictures. It appears that at one time the previous owner painted them black. No idea why, but he made a mess of it. About half of the bezels that I removed from the rims have paint on them. Easy fix though.
So much for the pics...for some reason I am unable to upload them. I'll keep trying.
Last edited by chip-powell; November 12th, 2018 at 02:08 PM.
Reason: saving pics
You need to do the math. 225/75-14 (if you can find them) is 27.3" OD. 225/70-14 is 26.4" OD. 225/60-14 is 26.05" OD. The difference between 75 and 70 is 0.9". The difference from 70 to 60 is 0.35".
The 225/60R14's are 24.6" tall. Myself and few others have found the BFG's shorter than they advertise but it gives an idea.
if you like the ssII style I would suggest you hunt down some 15-7 ssIIIs, you will find many more tire options and the rims will look essentially the same.
the bolt on ctr cap IMO does look a little nicer than the snap on style, but most will never know the difference, the snap on ctr cap rims like you show came in 14-6, 14-7, and 15-7. You can find a stamp on the rim that will state the size.
The 225/60R14's are 24.6" tall. Myself and few others have found the BFG's shorter than they advertise but it gives an idea.
You are correct. The secret to doing math is that you have to type the correct numbers. For example, say you type 255 instead of 225, you get a much larger diameter (like 26" instead of 24.6")... Sorry about that.
FYI, it's fairly easy to refinish wheels. I redid both the 14x7 original wheels that came on my car and a set of 15x7 wheels that I bought locally.
The 14x7s I stripped with oven cleaner; the 15x7s I had media blasted at a local welding shop.
I primered both with rattle can etching primer, sprayed the backsides with rattle can black paint, then sprayed the fronts with a Preval sprayer and body color paint.
Below are finished results of the two different wheels.
One is a 14x7 bolt in center cap, the other is a 15x7 snap in center cap, both with with 245-60 tires.
You need to do the math. 225/75-14 (if you can find them) is 27.3" OD. 225/70-14 is 26.4" OD. 225/60-14 is 26.05" OD. The difference between 75 and 70 is 0.9". The difference from 70 to 60 is 0.35".
And you need to not presume I was talking about height.
The raised center circular portion of the wheel has five notches where the center cap snaps in.
The bolt-in style doesn't have that raised center part and there are five bolt holes, one on the end of each of the "points" between the lug nut holes.
I wouldn't really worry about it - can you tell the difference in the two wheels I posted above? The average person would have no idea they are different unless they saw them side-by-side, and maybe not even then.
Last edited by Fun71; November 13th, 2018 at 09:28 AM.
Just my $.02 but I wouldn't put the $$ and time into restoring 14" rims with snap on caps. Get some 15's so you have more availability with tire selection.
November 12th, 2018, 09:07 AM
