1983 Electra: Who Runs 235/75-15 ?

[SBRMD]

Recently acquired one, tires are old.  Factory tire is 215/75-15, diameter 27.7 inches.  Considering upsizing to 235/75-15, diameter 28.9.  Anybody with experience here?  Interested in comments for any full size Buick 1980-85, I think they'd all apply, probably 1977-79 too.  Outside of the obvious speedometer error, I'd like to know if people experience any rubbing, etc.  Seems to me that the wheel wells are quite roomy.  Thanks to all in advance 

[60FlatTop]

That is a big tire. I would stick with the original specification. Thousands of them were worn out on those tires. I remember a term called "over-tired" some guys used that might apply.

Kind of goes along with wanting a 4 core radiator, new station wagon springs, and those other Heavy Duty things that are the topic when uncles get together in the living room after dinner.

[SpecialEducation]

Pretty sure my ‘82 used 205/75s. 215 might have been an upgrade size, but I don’t think I’d go much bigger than that. I’d certainly downsize the series if I went bigger. I often thought 225/50s would look good on her, but I think we figured anything wider than 215 would rub. 

[SBRMD]

215 is standard and 225 is the upgrade size.  So certainly no rub with those.  Just want to know if anyone has used 235 and gotten any rubs.

[NTX5467]

NO need for a P235/75R-15 tire on that 4000lb car.  PERIOD.  Even a P225/75R-15 tire can be too large/tall, too.  If you want something a little bit wider, aim toward a P225/70R-15, which should be the same revs/mile as a P215/75R-15 tire.  Even in whitewalls, in some brands.

 

NTX5467

[Lesabre T-type Chris]

Hello,

 

I own a 1977 Buick Riviera.  The 1977 and 1978 Rivieras were the last RWD Rivieras and they were built on a version of the GM B-body platform.  LeSabres and Electras are also on this platform from 1977-84 (through '85 for the Lesabre...).   I researched tire sizes quite a bit a few years back so I can give you some insight on your question.

 

When I bought my Riviera back in 2017, the previous owner had been running P205/70R-15 Blackwall tires on it.  In my opinion, they were way too small.  The car sat too low to the ground so it didn't look right from the side and I had to be careful about frequently 'bottoming out' when going over bumps, hills, driveway approaches, etc...  Also, when looking at the car from both the front and rear the proportions looked way off to my eye.  It looked like she was on ice skates because the tires were so skinny!

 

I did a bunch of research on the original factory options for tires for my car.  What complicated things was that for a few years in the 70's a metric tire size was used in the US--something along the lines of GR-15, HR-15, etc...  Anyway, I found that the HR designation (which was an optional size) was an equivalent to P225/75R-15.  Interestingly, I also found that a white-letter tire option was available from the factory!  I wanted my Riviera to have a little more sporty look to it so I went with white letter BF Goodrich Radial T/A's.  I could not find P225/75's but I was able to find P235/70's.  They fit perfectly and filled out the wheel wells much nicer.  When you look at her from the front and back the proportions also look much better.  A little muscular but not over the top!  I have 15x6 Buick Road wheels (5x5 bolt pattern) and love the look.  I will see if I can find a photo and post it (she is still in winter storage right now).

 

I have not had any rubbing issues.

 

Chris