Uncle Hulka

I had no idea tire choices could be so frustrating!

The car in question is a '69 Cutlass S. I am replacing the original 14x6 SSI wheels with a set of 15x7 SSII that I picked up. The SSII's came with two, 235/70/15 BFG Radial T/A's that are in great shape with lots of tread (90%).

I would like to buy another pair of BFG's, but I don't know what size! It will be street driven 99% of the time, but I plan on running her at Musclepalooza. I have 3.91 gears behind a 455/TH400 so I would like to get a fairly tall tire. I was thinking of running the 235/70/15's up front, and putting 255/70/15's in the back. That size would hopefully let me get off the line and let me drive at 65 mph@3000 rpm.

Is this combination is a poor choice? If I can't match the 235/70/15, I'll have to get a matching set in a more appropriate size, but finances would mandate Cooper Cobra's.

What do you guys think?

DoubleV

My thoughts are that with all the research I have done on the radial TA's, it is my belief they are just a flat out shitty tire as far as performance goes. They are popular because they come in 'muscle car' sizes and they look cool ( RWL ). Unfortunately there are not alot of alternatives. Cooper Cobras are one like you mentioned. Firestone Firehawks were good ( for this class of tire ) but have been discontinued.

I don't think your combo you are considering is a poor choice but it's not the greatest either IMO. Those 70 series tires are going to be very tall. I personally would not like that look. Maybe you're OK with that though. I would also think they would be a bit mushy on turns too.

If you're OK with buying new tires all around, I would strongly consider the Mickey Thompson Sportsman S/T's. They look just as good as the BFG's but have a speed rating 1 higher which would mean they are a more sturdy/stable tire. They have a tread similar to the Cooper Cobras but they are different and look to be a bit better for traction. They are cheaper than the BFG's too, but not by alot. 235/60's up front and 255/60's in the back is what I would do. Tire height would be about 26" front/27" rear with that combo. If you want to go taller in the back and can fit them, go with the 275/60's in the rear which would be about 28" tall. Either of those seem better to me than a 29" tall radial TA!

Uncle Hulka

Now that's a well reasoned reply, DoubleV! I appreciate your input and I'm going to look into pricing the Mickey Thompson's. I've pretty much reconciled myself to abandoning the 235/70/15's I have and buying 4 new tires. Opens up a lot of choices!

Now I personally would love to run the 275/60/15 out back with 235/60/15 or 245/60/15 up front. My concern is that I am running a 15x7 rim. The smallest recommended width for the 275's is 7.5".

What are your thoughts on running the 275/60/15 on a 7" rim?

coppercutlass

What about the drag radial t\a 's they worked very well for me and where too soft on the street to where they wore down fast and they are a full pattern tread tire.

DoubleV

Never done it but there are those who have and claimed they were fine. They will bulge out and give you that bloated look though. I'm sure they would work but not be ideal. Remember not all tires listed at a certain size are really the same size. Some tires are flat out bigger/smaller than others even though they are listed as being the same.

It may not be in your budget right now, but there are places you can go to get a wider rim put on your wheels. A 15x8 SSII would be nice.

One option is to run the 275 on the 7" rim for now and plan for converting 2 of them to 8" when the funds allow ( or just get 2 new 15x8 wheels ).

If you want to really hook up, drag radials are way better than any street tire ( especially the 15" options we have now ). A 255/60 Mickey Thompson drag radial would fit perfect on a 7" rim and be 27" tall. Just don't expect them to last long on the street and if you plan on doing alot of driving in the rain than make sure you have an up-to-date will!

coppercutlass

I had 275-50-15 on my 15x7 rallye wheels and 275-60- 15 the 50 series bulged out but looked great the 60 series looks pretty good. I have pics of both on ralyes wheels on my car I can share if you want o see what it looks like.

oldsmobiledave

275 60 15s are two wide for a 69 rear wheel well. With your 3.91 gears the 275 50 15 is too short a tire.

235 60 15 up front and 255 60 15 out back is the answer on 68-69 A body cars. Try 18 lbs air pressure on the drag radials for best 60 foot times.

chadman

That's what I have on my '68 and it is a good look.

Uncle Hulka

I've been wrestling with this long enough. The255/60R15 rear and 235/60R15 front setup was my initial thought way back when I started this journey. But then I started envisioning fat, fatter, fattest skins. I feel confident in that setup, knowing I considered all my options first.

Thanks to all for sharing your wisdom and experience!

Magna86

I run 255/60R15's on all 4 corners. Look great and I can maximize tire life through rotations.