What size wheels?

[Mean50]

I plan on switching to 28X12.5 ET streets and I was wondering what size wheel would be best. I know that 9 inch wheels with 5.5" back spacing will fit the car, but I was wondering if I could get a 10" to fit. If it would, would it have to be with a 6" backspacing, b/c I don't think there would be enough room to the inside to go with a 6.5" backspacing. Would a 9" wheel be too small for the 28X12.5s? It is on a 89 coupe.

[Dark_5.0]

You will have to roll the fenders and beat the ***** out of your car to get those tires to fit.

Been there done that.

Stick with the 10.5's

[andy669]

Yeah, exactly what Dark_5.0 said. Why do you want to run such a big tire?

With a rearend that is stock width, a 10" rim usually has a 6.5 backspace. You'll need to do a little clearancing on the inners. I took me about 20 minutes to do both of mine.

Andy

[drudis]

Although this is for roadracing... Here are some install photos of 17x9-1/2" wheels with 6.6"BS and 275 tires:
Link: http://www.dariusrudis.com/mustang/wheels/

[Mean50]

I have 26X10.5 on it now, and it needs a little more traction. I am going to play with the pinion angle some when the track opens. I need the 28" tall b/c I am crossing the 1/4 mark at 7000rpm now. The only time my car has ever hooked good was at FFW Bristol. I have tried coming off the line on just the motor, then hitting the juice and it still breaks loose. I will at least go with the 28X11.5s on a 9 inch wheel.

[andy669]

Pinion angle is not going to do a whole lot for traction. What is the rest of your suspension set up like?

How old are your tires? I can tell a difference in the way mine hook after 10 passes. After 30, they are shot. What pressure are you running in them?

I think going to a bigger tire is just going to be a band-aid fix for your traction problems. I'd look in to getting the rest of the suspension in order, first. Do you know what your car weighs, how about your weight bias?

I think with the proper suspension set up you should be able to hook that thing on a 26x10. Then if you need more top end you could step up to a 28".

Andy

[420nitro]

Originally posted by andy669
Pinion angle is not going to do a whole lot for traction. What is the rest of your suspension set up like?

How old are your tires? I can tell a difference in the way mine hook after 10 passes. After 30, they are shot. What pressure are you running in them?

I think going to a bigger tire is just going to be a band-aid fix for your traction problems. I'd look in to getting the rest of the suspension in order, first. Do you know what your car weighs, how about your weight bias?

I think with the proper suspension set up you should be able to hook that thing on a 26x10. Then if you need more top end you could step up to a 28".

Andy

Andy is right on the money. Mean 5.0 try to spend more time with your suspension and chassis. You should have no problem hooking up on a 10 inch tire. You will also go faster on a smaller tire. Just about everybody I know that has a 10 sec. car is hooking up on a 10 inch tire! The only guy that comes to mind that has to run a bigger tire is a Mustang that weighes under 2700lbs w/driver (9 sec. car)

[420nitro]

Hey Mean 50,
I just saw your list of mods on the "user rides".
With the nitous on, I would definitely run 28x10.5 slicks! On motor run the tires you got.

[Mean50]

According to a lot of local drag racers and articles that I have read Pinion angle does affect traction. Getting just the right amount of negative pinion angle will help. If not then why else would they make adjustable upper control arms, or even ladder bars; it is to tune the pinion angle. I have southside machine lift bars on the rear and I am in the process of getting 90/10s and trick springs for the front.

Most of the mustangs that run in the elevens or the tens at Bristol have at least 11.5" tires on them. I have looked at several cars and talked to the owners. During something like FFW they prep the track exceptionally well and I can hook on the 10.5s, but that doesn't help the rest of the race season.

Take a look at www.photomagic-digital.com for the Thunder Valley Fun Ford Weekend (true street) pictures and see what you all think of how my car hooked. It is white with red stripes and a small pro-stock style scoop (tag is Mean 5-0). Thanks!

[420nitro]

Originally posted by Mean50
I have southside machine lift bars on the rear and I am in the process of getting 90/10s and trick springs for the front.
5-0). Thanks!

I assumed that you already had 90/10s and front drag springs
After you do that and have the battery in the trunk you should have no traction problems.

I used to street race with 70/30s and 4 cylinder springs in the front. 50/50 rear shocks and Fairmount springs in the rear with an air bag. South lift bars and the battery in the trunk and a 6 point bar. This car would hook and lift the tires (a little bit) on the street with 26x10 M/T drag tires!!!! This is spraying the car with a 175 dry shot from NOS with 4.10 gears!!! Car ran 12.40 off spray. Don't know how fast w/spray but beat ALOT of mid to low 11 sec cars!
Is the issue you want to hook on D.O.T.S or does it matter if your on run on drag slicks?

[Mean50]

The main goal is for the true street class and street nights at the track, so I will be using MT ET Streets! I know that the struts and springs will help a lot, so hopefully it will be okay. Since I have to go to the bigger 28" tall tire I figured I would go wider as well. Maybe the 28X11.5s would be the way to go.

[andy669]

You can play with the pinion angle til the cows come home. Its not going to turn a tire fryer into an instant hooking machine.

If you have solid control arm bushings the pinion angle should be negative 1-2 degrees. If you are using rubber bushings it should be negative 3-4. Basically what happens is, during launch the rearend will want to rotate up. Setting the pinion angle negative will bring the pinion straight inline with the driveshaft during launch giving you the most efficient power transfer.

I have friends that run 9.70's in a 3300 lb stick car on a 26x10.5.

Andy

[Mean50]

Was the 9.7 run on drag slicks or on DOTs??? The 10.5 ET DRAG is wider than the 10.5 ET STREET!!!

[420nitro]

Originally posted by Mean50
Was the 9.7 run on drag slicks or on DOTs??? The 10.5 ET DRAG is wider than the 10.5 ET STREET!!!

Ok, calm down..
Look,.. M/T is a little misleading when they come to there tires.
Yes there drag tires are bigger then there ET streets.
Heres the info on sizes, and you decide.

M/T drag slick on a 15x8 rim (28x10.5)
10 inch tread
11.7 sec.
28 dia.

ET Street on a 8 inch rim (28x11.5)
8.6 tread
10.9 sec.
27.5 dia

Et street on 10 inch rim (28x12.5)
9.9 tread
12.5 sec.
28.2 dia.

If I was going to run d.o.t.s, I would try the 28x12.5 tires on a 9 inch rim first. Try to bring down the sec width enough to hopefully get as close to a 28x10.5 drag slick as possiable, because I know for a fact the 28x10.5 drag slick fits on a 8 inch rim on my car!
Good luck and hope this helps.

[Mean50]

Thanks!!! I will try the nine inch wheels with the 28X12.5s!!!