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Discussion Starter #1
Ok guys, this search has turned up some people with all different kinds of info, none that really truly states whether or not this will work. Now for reference I used to have a 295 50 15. The tires had a nice wide stance, but barely had the height to get a nice bite with. I also had a 8.5in rim with a 3.75in backspacing, so the wheel stuck out towards the wheel well and would hit on the fender if the air shocks blew, plus they had to be jacked up to keep me off the tires. This caused issues with being able to hook as the shocks messed with geometry and caused horrible wheel hop and thus I had horrible initial times. The new engine is a 521 with 620+ hp and 670+ torque. So I plan to change the rims to either a cragar ss polished or a torq thrust polished. (Note: opinions on this are welcome!) So it will be a 15x8 with a 4.5 in backspacing. Now considering the old rim was a 15x8.5 with a 3.75 in backspacing, the new rim should in theory pull the tire in towards the frame approximately an inch to an inch and a half by changing the size and the backspacing right? If so, do you guys think the 295 width will still fit? Does anybody know if a 28x12x15 tire will fit, this would be ideal so that I can use the Sportsman s/r tire. Otherwise I will be stuck taking a safe route of 275 60 15, which I lose an inch in width, but gain an inch and a half in height at least. I would love to see pics if anyone has them of this year with the tires on the back, plus rim types! Thanks in advance!
 

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Ok guys, this search has turned up some people with all different kinds of info, none that really truly states whether or not this will work. Now for reference I used to have a 295 50 15. The tires had a nice wide stance, but barely had the height to get a nice bite with. I also had a 8.5in rim with a 3.75in backspacing, so the wheel stuck out towards the wheel well and would hit on the fender if the air shocks blew, plus they had to be jacked up to keep me off the tires. This caused issues with being able to hook as the shocks messed with geometry and caused horrible wheel hop and thus I had horrible initial times. The new engine is a 521 with 620+ hp and 670+ torque. So I plan to change the rims to either a cragar ss polished or a torq thrust polished. (Note: opinions on this are welcome!) So it will be a 15x8 with a 4.5 in backspacing. Now considering the old rim was a 15x8.5 with a 3.75 in backspacing, the new rim should in theory pull the tire in towards the frame approximately an inch to an inch and a half by changing the size and the backspacing right? If so, do you guys think the 295 width will still fit? Does anybody know if a 28x12x15 tire will fit, this would be ideal so that I can use the Sportsman s/r tire. Otherwise I will be stuck taking a safe route of 275 60 15, which I lose an inch in width, but gain an inch and a half in height at least. I would love to see pics if anyone has them of this year with the tires on the back, plus rim types! Thanks in advance!
1) What city do you live near?
2) For a good lanch you need weight transfer. Try drag shocks? 2 or 4?
 

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Discussion Starter #3
I went with Monroe sensatracks simply because rear drag shocks are a 50/50 generally, not much different then a regular shock, the fronts I have thought about changing to a 70/30 shock, I think 90/10 would be too extreme! For the meantime, I still have Monroe sensatrack on the front as well, the air shocks were so jacked up you could wiggle the springs in the cups, thus the car was fully riding on the shock, which was too rigid for a good launch. I just really want to use 28x12x15 if possible, but from the searches I have heard only 275 60 15 is the only size that will fit under this car, anybody know for sure?
 

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Discussion Starter #4
Ok, well no comments yet on any info, so I ordered 28x11.5x15 mickey Thompson et streets. I ordered 26x8x15 for the front, sportsman s/r tires, and I ordered the polished aluminum torq thrust II wheels. I got the 15x7 with 3.76 backspacing and 15x8 with 4.5 backspacing. I will comment with pictures and fitment on stock suspension (minus adjustable upper, lower, and panhard bar) but the shocks and springs are stock but new. So we shall see how these fit in the hole! Parts will be here in like 4-5 days. More to come then with pics!
 

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Discussion Starter #5
Ok, so here it is.....15x8 with a 4.5 backspacing and a 15x7 with 3.76 backspacing all fits top notch here. The front 26x8x15 could have been a little wider and not hurt a thing, but they look good the way they are. As for the rear, I have an adjustable upper/lower/panhard set up. I need to move the panhard bar to pull the wheels towards the drivers side. I have 1'' on the drivers side between the wheel and fender lip, and 1/2'' between passenger tire and lip, so if I move it a quarter inch, both sides will have 3/4 in space with the 275 60 15 tire. Also, there is about 1 1/2 in between the frame and rear wheel. If one were to use a 8 in with a 5 or better yet a 5 1/4 backspacing there would be plenty of room for a 295 tire if anyone is wondering. Here are the pics of the torq thrusts installed, nice to finally have it ride on suspension over the air shocks....
 

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Going off of my old school experience I suggest not using air shocks and going to a drag shock front and rear. Also have you replaced all your control arm bushings? If not I would suggest poly ones which should straighten out yout rear end shift. If I recall Sphon I think it is makes upper and lowers for these. I do also know that pinion angle does make a difference but only know the guy to talk to about it and it isn't me lol. Move the battery to the rear and take some weight out would be other areas to look at.
 

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Discussion Starter #7
I am running the spohn setup..they are great due to adjustability..strength..etc. i am also running poly bushings up front as well!
 

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Hey, I'm new to the forum and I only hope I'm going to the right place with this question. I've got a '64 Galaxie 500 running on 14" wheels. I want wider tires all around but understand that I will have to step up ot 15" wheels to get a wider tire...what are the considerations?
djones525
 

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Welcome, DJ

You can probably get some pretty wide tires for 14" diameter rims, wider than for a 18" rim, for example. That's because on the big wheels the tire is low profile and can't stick out much past the rim. If you get too much stick-out though, it gives a balloon look, kind of goofy, imo.

The critical measurement for tire width is wheel width: 7", 8", etc. The wider that measurement is, the wider a tire it can take.
 

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Ford - I run a 27x 11.5 quicktime pro with 5.5 bs and it looks very close to yours. On hard launch it would hit the wheel lip. A passenger side airbag with 10psi took care of that with out raising the car.
 
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