M/T 325/50-15s

[87SS]

I have the chance to purchase a pair of used M/T ET Street Radials 325/50-15s for $125 for the pair (not many passes on the tires at all).

I realize I will have to do a full notch to the inner most section of the frame, roll or cut the lip, mini-tub and probably use a wheel with 5.5 BS (or somewhere around there)etc.

I was curious if anyone has regretted using this size radial. I see a lot of people running the 295/60s and I believe they are a couple of inches taller and slightly narrower. Since I will be doing a notch either way, I figured if the 325s were too wide I would pass on the sale and go with the 295s. At the stage I am at now fixing all the frame and body issues (frame off) I would not consider purchasing the tires, but it appears to be a good deal and I planned on notching the frame anyway within the next few weeks and thought this would be a good time to plan ahead.

These will be on a G-Body width rear and I have not selected a gearing yet. Also (if this is important) the motor will be a twin turbo 406, but not until later next year. Until then it will be a pump gas 406 N/A.

 

[Mark 79 Monte]

I have those tires on my 79 Monte. I've not regretted it, but I've considered switching to the 295's after i wear these out. I don't have any issues with them being too big, they fit inside my modified wheel wells just fine with a 5.5" offset.

 

[87SS]

Thanks!

 

[10secBu]

I've run 275/60's, then 295/65's earlier this season, then back to 325/50's just recently. For my combination with 4.10 gears, the 30" tall 295/65 killed too much effective gear ratio. The 325's were much more intune with what the car wanted gear/rpm wise. The thing now is I can keep the 325's with the 4.10 gears or go back to the 295's with a 4.56 gear.

The 295 really fills the wheel well, but gives the car too much rake for my taste. The 325 just has a more level stance. I can't lower the back end anymore for the 295's without messing up the rear suspension geometry, plus the shocks would wind up being too long and are compressed most of the way. With a slightly shorter spring I have here, the shocks only have 2" of usable compression compared to 2 3/4" with the current spring.

Sure wish QA1 stocker stars (dbl adj) were made a bit shorter.

EDIT: I initiall installed the 295's as the taller sidewall will give more consistent traction on a marginal track. This taller sidewall is more forgiving and will give the tread a better chance at staying hooked. I don't have many passes on the current 325's, so time will tell how they will do on marginal start lines the rest of the season.

 

[87SS]

I've run 275/60's, then 295/65's earlier this season, then back to 325/50's just recently. For my combination with 4.10 gears, the 30" tall 295/65 killed too much effective gear ratio. The 325's were much more intune with what the car wanted gear/rpm wise. The thing now is I can keep the 325's with the 4.10 gears or go back to the 295's with a 4.56 gear.

The 295 really fills the wheel well, but gives the car too much rake for my taste. The 325 just has a more level stance. I can't lower the back end anymore for the 295's without messing up the rear suspension geometry, plus the shocks would wind up being too long and are compressed most of the way. With a slightly shorter spring I have here, the shocks only have 2" of usable compression compared to 2 3/4" with the current spring.

Sure wish QA1 stocker stars (dbl adj) were made a bit shorter.

EDIT: I initiall installed the 295's as the taller sidewall will give more consistent traction on a marginal track. This taller sidewall is more forgiving and will give the tread a better chance at staying hooked. I don't have many passes on the current 325's, so time will tell how they will do on marginal start lines the rest of the season.

Thank you. I know what you mean by too much rake. I would rather have a more level or close to level shot front to back. I have seen the 295s on a couple of cars and it really does fill that wheelwell up. I think I will try these for the price I am getting them for and see how they work.

Thanks again.