I a trying to decide what i should run for my 83 t/a with a 383 build up in progress. Should i go with some sticky 15"ers like the indy profile S/S or something else for 16" or 17"? I need ok treadwear as i am a HS student still (last year baby!)
Will i be able to squeeze either of these in?
345/50-15
275/60-15

what offset will i need to run for 15x10's in the back. Ill run the indy profile out front if i go w/ the S/S's

 

the 345/50-15 will be to wide unless you are running wheels with a different backspacing

I run 295/50-15's on the rear and I had to do some mods to the inner fenders for clearence.

the largest tire I have ran on the front was a 235/60-15 , they dont rub anything but to go as large as a 275/60 on the front I would say there going to rub.

 

anything bigger then 275 is gonna do more harm then good

 

I cant fide the specs on a 345/50-15 tire but I bet its close to 28 or 29 inch tall tire with aroung a 11 inch width
where as a 295/50-15 is 27 inches tall by 10 inches wide

and a 275/60-15 is 27inches tall by 9 inches wide
compared to a 235/60-15 is 26inches by 8 inches wide

 

heres a pic of the 295's im running out back.

 

the pictures are from my picture phone and are not the best quality but you should get the idea, im sorry the tires are dirty. as im going to repaint the car soon, the tire on the right rear is almost bald right know I will try to get a better pic from the rear of the car . only from the rear can you tell just how wide the tires really are.

 

I was planning on running a larger backspace, thats why i was wondering how far out id need to make it.

From:
http://www.jegs.com/cgi-bin/ncommerc...56&prmenbr=361

Estimated Metric Equivalent: 345/50-15
Tire Overall Diameter: 28''
Tire Tread Width: 11.8''
Tire Section Width: 14.1''
Wheel Diameter: 15''
Approved Wheel Width: 8'' - 10'' - 11''
Tire Weight: 40.0 lbs


Estimated Metric Equivalent: 275/60-15
Tire Overall Diameter: 28''
Tire Tread Width: 9.5''
Tire Section Width: 12.3''
Wheel Diameter: 15''
Approved Wheel Width: 7'' - 10''
Tire Weight: 37.0 lbs

I figured with some good suspension setup, the 11.8" tread would hook unbelievable with a burnout (get even stickier as they get hotter, they say rear only b/c of that. )

Either

Estimated Metric Equivalent: 235/70-15
Tire Overall Diameter: 28''
Tire Tread Width: 6.5''
Tire Section Width: 9.2''
Wheel Diameter: 15''
Approved Wheel Width: 5.5'' - 6'' - 8''
Tire Weight: 31.0 lbs

or

Estimated Metric Equivalent: 215/70-15
Tire Overall Diameter: 27''
Tire Tread Width: 6.0''
Tire Section Width: 8.5''
Wheel Diameter: 15''
Approved Wheel Width: 5.5'' - 6'' - 7''
Tire Weight: 27.0 lbs

out front. Same tire line, just not as reactive to heat so they will be better for front/handling.

Any idea of the tread wear of these?

Some pics would be wonderful, i am curious how big these are actually going to look.

 

Whoa... upon further searching, mickey thopson just came out with the Sportsman S/R Radial street tire. They look pretty mean. http://www.mickeythompsontires.com/s...rtsman_sr.html they even have them in 26" diameter to fit nicely. Just called jegs and they said they can order them in any size MT makes. Looks like they would have some decent tread wear to boot. Kinda pricey at over 250 each for the rears. Would go with somehting different for the front though... Indy's looking pretty nice for the dough compared to these. Hmmm... decisions decisons.... any one have a couple thousand dollars laying aroud they want to give me?

 

as soon as I can im going to take pictures of the tread on my tires. they are almost bald!. and I have done a few burnouts the longest burnout I have done was right at 150ft and that chewed about 1/4inch rubber off my tires.

If you want to do major burnouts and not burn up you'r pocket.

get a set of dirt cheep tires for the rear for when you want to smokem! and a good quality set for when you want the car to just take off like a rocket and not sit there spinning the wheels.

.also a few weeks ago I saw an episode of horsepower tv and they showed a tool it was a guage for finding the wheel offset and backspacing, it looked so easy to use, but I dont remember much else about it or who makes the tool.

 

they tend to be about 26.5 with about a 9-10” tread width, 11-12” section width depending on the wheel you mount them on.

they tend to be just over 28” tall and about 8” or so of treadwidth, 10-11” section width on street radials. Drag radials tend to run bigger.

Darrell, are those stock firebird rims that you have those 295’s on? If so they’re either the narrowest 295’s or the widest stock rims that I’ve ever seen, can you take a picture of them at an angle so I can see how much they bluge on the rim (they should be too wide to mount on that rim). BTW, what picture phone do you have? Those are some of the better picture phone pictures that I’ve seen (I plan on replacing my phone this weekend…).

I’d go with a 26 or 26.5” tall tire in the front, 235/60/16’s (26.1) fit very well, the stock tires are between 25.5 and 26.1” tall

The 275/60/15 look a bit ******* on the back of the cars, but do fit well, sometime requiring a little bit of clearancing of the wheel well (just some quick work with a hammer, in my case with DR’s they didn’t really need it but there were a couple of places that you could see that they were lightly touching once in a while and I did it just in case).

 

The bottom line is that you should buy a set of tires having a speed rating one above what you think you car is capable of.

And (for the speedo to read correctly) you want a tire of the same DIAMETER as the stock tire diameter. The aspect ratio doesnt mean anything here except for getting the correct OD for a given rim diameter, that will lock in the aspect ratio that you need.

Having said the first statement:
speed rating of tire,,, max speed of tire
..........S............................112
..........T............................118
..........U............................124
..........H............................130
..........V............................149
..........W...........................168
..........Y.............................186

So, first how fast is your car going to be?, and what is the factory tire diameter?, and what rim diameter do you want to use?

I can pick the right tire size for you if you get back with the info above.

 

here is a pic I have, I can get a better pic of the tire , on or off the car, tomarrow I will be pulling the rear axels to replace some leeky seals.

 

and the wheels are stock , it was a real pita to mount the tires on the factory rims.

the phone I used to take the pics with is a sony ericsson model Z500A. I wished it had a built in flash to brighten up the pics a little more.

 

Top speed: Whatever an aprx 400+ hp 383 can push it too.

Diameter: 26" diameter, however, doesnt matter as i am changing gear ratios, and running an electronic speedo so can easily recalibrate.

Rim Diameter: I have 15x7 Rims, would like to keep them as i have put a good deal of work into polishing them so far. Looking for something wider in the back, sticky would be nice but i still need some decent tread wear.

Those tires look nice Darrel. Nice stance, considering going even a little wider for a little more agressive look.

I guess the indy profile S/S is not very good for tread wear according to hot rod but they get the power to the ground. Also, Anyones opinion on the Firehawk Indy 500?

 

P235/60R15 is 26.1" in diameter and the design rim width is 7.0".

Now you need to find a tire company that makes that size in a W or Y speed rating.

 

I checked my tires and I have a few better pics of them.

the pic here is with the tire off the car so I could get a better pic of it and if you can make out the tire's tread width is 11 inches on the wheels it is mounted on.

the tires are to wide for the rims but they do look and grip the road just fine.

 

this is how much of a buldge there is

 

at a closer look

 

and with the height they are actually less than what they should be

 

if you look to the right of the ruler you can see "105S" that is the speed rating

 

also the fender lip height with the car sitting level .


and one last thing . if you can afford them try to get a tire with a v or higher speed rating .

the tires that im using came from my old 69 chevy pickup , I used them on both front and rear of that truck untile I sold the truck.

I thought it would be a smart swap. to use them on my trans am, and I would have 2 spare tires. bad part is a spare that big wont fit in the rear hatch of the car.

 

Thanks for the kick *** pictures. They helped alot actually. I will be looking into tht size. Thanks!
I am not aware of any company that makes V rated in that size, S is the highest i know of. Do you know of one?

 

I have found that TOYO PROXIES ST 295-50r15 has a H speed rating , not as good as a V rating but an H = 130mph and V = 149mph.

 

partially correct. "s" is the speed rating, 105 is the load rating.

Here's a chart reference-
Load Index -Pounds

71 -761 / 91 -1356
72 -783 / 92 -1389
73 -805 / 93 -1433
74 -827 / 94 -1477
75 -853 / 95 -1521
76 -882 / 96 -1565
77 -908 / 97 -1609
78 -937 / 98 -1653
79 -963 / 99 -1709
80 -992 / 100 -1764
81 -1019 / 101 -1819
82 -1047 / 102 -1874
83 -1074 / 103 -1929
84 -1102 / 104 -1984
85 -1135 / 105 -2039
86 -1168 / 106 -2094
87 -1201 / 107 -2149
88 -1235 / 108 -2205
89 -1279 / 109 -2271
90 -1323 / 110 -2337

 

arent the proxies a light truck/SUV tire though? Wouldnt that hinder the grip a little? What about running the BFG Gforce sports in the front (yes i know they are a sport compact tire) and the BFG Drag radials in the back? I wouldnt remind replacing those occasionally as they are only a 135 a tire or so.

g-Force Sport Tire,
225/50R15 $85.99

G-Force T/A Drag Radial Tire
P275/50R15 $136.99

The sport tires would have a decent tread wear so i wouldnt have to replace all 4 that often, the Drag radial probably would have some decent cornerning abiltity too. 2 drag radials every now and then? I can handle 270 once in a while, If im nice im sure i could get quite a few miles out of them.

 

Speed ratings only apply to “sustained speeds over ____” If you really think you’re going to be spending a half hour or so at 180mph or so then have at it.

225/60 and 275/50 F/R tire sizes with a DR on the rear… I’ve been debating buying some big wheels (15x8 F and 15x10 R) and running those on the street, with a Nitto DR. I’d be happier with a 235/60 on the front and a 295/50 on the rear, but I don’t know of anyone that makes a _really good_ 295/50.

 

How do you like it? that's one of the ones that I can get for free with my current plan. It's supposed to have a built in brightness control for the pics...

All I really want is a reliable phone, the camera phone thing would be nice and a calculator that is fairly straight forward to use (ie, doesn't **** me off) and can do basic scientific functions.

 

I have searched online, and there's not very many companey's that make a 295-50-15 , either they are for sport trucks or sport compacts.

If you know what your total vehicle weight with you and how ever rides with you plus and cargo. lets say you would be somewhere in the nieborhood of 4600 lbs ( my guess), and letts say on the weekends you head to the track to shedd a little smoke. and still drive the car anywhere at anytime of year reguardless of weather, then you should consider buying 2 sets of tires or you will have to make a compromise, and sacrifise a little performance for a little driveability.

if you are realistick about what speeds you'r car can reach on the track, and know what the total weight of the car, than you can call local tire stores near you and , dont ask them , but tell them what you want, as they will only insist on selling the correct size (factory)of tire for your car.

also from my white knuckles last winter, dont try to drive a car with a 295-50 on snow. I had to build up speed to climb a hill, and at half way up the rear would break traction and go sideways with me. I drove down a one lane blacktop country road for 48 miles . it would have been fun if my wife sitting beside me wasnt chewing my head off .

one more thing I measured my backspacing on my factory wheels and came up with 4 1/2 inchs.
if you'r going to buy a set of wheels ? try to get them with about 1 1/2 - 2 inch addition clearance for the inner fenders. if you plan to run anything wider than 10 inch.

 

It's awsome to be a free phone.

the built in brightness doesnt do a whole lot for the pics I posted. the phone needs to have a built in flash. then I would say the phone ROCKS!

 

This is a summer only car. So sacrificing treadwear and all weather isnt huge but i dont want to replace them more then once every year or two. Yes i know driving in the snow is a ***** because i did it with bald 245/60-15's all the way around (Radial T/A's none the less) boy i would have had better luck driving a buttered snake. That was truely a bad choice. Hit the curb alot so i probably broke something, hit a street sign and broke my grill on the driver side, and found it literally impossible to make it up the hill to my house, had to take aback road. 2 sets of tires is an idea. Because my rear wont be built for a while and my engine will be able to tear it apart i will have to drive it super nice, a set of street tires like the indy 500's wouldnt be a bad choice. They come in 295/50-15's i believe. Not reccomended for 7" wide rims but oh well, just keep the pressure low i guess. the 275's arent a bad choice as you only lose .9" of tread http://www.bridgestonetire.com/tires...productid=1056
When im on the prowl, car shows, or racing, i could run drag radials possibly. The N-555R I hear gets impressive tread life for a drag radial.

 

I ran 33x12.50 tires on my jeep with 15x7 (actualy measured out at 6.7 in wide. for a while and did'nt have any problems...then I got rid of it. lol. The buldge look is sick! lol. I think I'm going to go to a 275 for the rear on mine though.

 

With a tall, offroad tire you want them on a narrower rim and they are designed for it… on a narrower rim they’ll flex more protecting the bead and the wheel and allowing the tire to conform to the odd surfaces that it is subject to better. It’s just the opposite of what you’re looking for with handling.

 

Great stuff here, but can someone please help me, I bought 4 Goodyear 245/50/16's and they are not wide looking, this from Goodyear. I want a wider tire as the Formula rims are stock WS6 16", can someone give better numbers from me to put on and be safe, Thanks! Andy