Sidewall width of a mounted 390-45-17 ?

[RandTx]

Can someone tell the measured sidewall width of a mounted M&H 390? and what width rim they are measuring over.
Looking for measurement such as the mounted tire laying on it's side from the floor to it's opposite sidewall.
or over a stack of 2 and divide by 2.
Thanks
Randy

 

[Trainman]

Randy... I just got a new set of 390-40-17 M&H's mounted on a Weld Racing Cheyene 5D 17 X 10 wheel and the sidewall width is 13 1/16 "

 

[RandTx]

Randy... I just got a new set of 390-40-17 M&H's mounted on a Weld Racing Cheyene 5D 17 X 10 wheel and the sidewall width is 13 1/16 "

Thanks that what I was looking for.
I figured it was quite a bill narrower than they spec..
My 325-45-17's are only 10 3/8 mounted on 9" rims

Dang at 13" on a 10" rim I can sure see why some people put em on 9" rims now.
Actually at 13" wide I think there is a chance we could widen a stock wheel , not rub on the inside, and have them stick out less than my 305 street tires.

 

[SlicksMH]

On a 12" wide rim, here is the spec.

S.W. 14.3

SlicksMH

 

[RandTx]

So how bad is it to run those on 9" rims?
with about 2200 lbs on the axle, under 110 mph, drag strip use only?.


Stock backspacing is about perfect on the 9's at 19 mm
if I widen a 9" stocker to 10 it's expensive and getting a tad too close on the inside.
On the 058 wheels: the 17x10 starts out with 1 3/4 too much offset widened to 12 they would still have 3/4 too much offset widened to 13 would be nice with a 1/4 more offset.
but considering that my 325's dang near damage the rims when I lay them on the side I 'd want the sidewall width at least 1 1/2 -2" wider than than the rim. that limits me to about 11 1/2" max
Boy they didn't make it easy to find an affordable light weight wheel solution for dodge truck wheels.

 

[SlicksMH]

So how bad is it to run those on 9" rims?
with about 2200 lbs on the axle, under 110 mph, drag strip use only?.


Stock backspacing is about perfect on the 9's at 19 mm
if I widen a 9" stocker to 10 it's expensive and getting a tad too close on the inside.
On the 058 wheels: the 17x10 starts out with 1 3/4 too much offset widened to 12 they would still have 3/4 too much offset widened to 13 would be nice with a 1/4 more offset.
but considering that my 325's dang near damage the rims when I lay them on the side I 'd want the sidewall width at least 1 1/2 -2" wider than than the rim. that limits me to about 11 1/2" max
Boy they didn't make it easy to find an affordable light weight wheel solution for dodge truck wheels.

The more you push the sidewalls in, the more the center of the drag radial comes up, the less contact patch you will have. Guys are running the 10"x17" and hooking up nice. Just last night Trainman, got a 1.65 60ty on the same wheel and here it is. :congrats:

http://www.vtcoa.com/forums/showthread.php?t=31090

SlicksMH

 

[RandTx]

The more you push the sidewalls in, the more the center of the drag radial comes up, the less contact patch you will have. Guys are running the 10"x17" and hooking up nice. Just last night Trainman, got a 1.65 60ty on the same wheel and here it is. :congrats:

http://www.vtcoa.com/forums/showthread.php?t=31090

SlicksMH

So is 9" wide just diminished traction issue vs an unsafe condition that would make the tires come apart or something?.
My longer term goal would be to have a set widened to 10-11" but for now I mainly need to see how it reacts to the taller tire diameter.
The 325's hook great most of the time. (on the same 17x9 rims)

 

[SlicksMH]

So is 9" wide just diminished traction issue vs an unsafe condition that would make the tires come apart or something?.
My longer term goal would be to have a set widened to 10-11" but for now I mainly need to see how it reacts to the taller tire diameter.
The 325's hook great most of the time. (on the same 17x9 rims)

No, you will be find on a 9" BUT you will not have all the contact patch to the ground.

SlicksMH

 

[RandTx]

Good deal. that's what I need to know to get the ball rolling.
Placed an order for a set O 390's this morning.
Thanks
-Randy

 

[dodgeram]

slicksmh your pm box is full

 

[SlicksMH]

slicksmh your pm box is full

PM sent. :rock:

John
MandHtires.com

 

[spedly]

Randy I'm getting ready to pick up a set of these too. Have you ran the 1/4 yet on them? What do you think of them with the 4.56s

 

[RandTx]

No At the Little River after the Killeen GTG last Sat, I ran on the 325's
I ran one night on the 1/8 went a smidge slower, but didn't do anything to try to up the launch torque. (still running the 3" x 18 torque tubes)
The 390's mounted up on 9" SST rims about 12 1/2 sidewall width, didn't measure but they were the exact same width as my 305-50-20's
On the 9's the contact are was reduced quite a bit, but they still hooked great.
I took the wheels in this afternoon to have them widened from 9 to 10 1/4 (all by increased backspacing) . Got my fingers cross that is going to work out and not rub on the inside going around corners or something.
Should be finished Fri, Ennis is open Sat but the forecast is for something like 2500 DA
If I get out there I'll probably try make comparison runs of the 325's to the 390's.

edit the pic is coming through, that a mounted M7H325 in the middle of unmounted 390's
huge eh?

 

[spedly]

Ok I think I'm going to order a set in the next few days. I'm assuming dealing directly with M&H would be best

 

[RandTx]

you swapping to 4.56's?
The 390 do look a lot better. almost look like they belong on there even without my truck being lowered. Still have the itch to sometime or another tub the bed a little and push the tires right up against the springs.
Think in the long run they will be just as fast if not faster.
What wheels are you going to try?

 

[spedly]

I'm just getting the eagle 058 since they are proven to work. I have 4.56s 4.10s and 3.55s at the house so I'll just play with gears until they work. I think the 4.56s are going to be about perfect though

 

[RandTx]

O58's should be a good wheels,then if you ever decide to widen them to 12 or 13 they'd still fit. Think 4.56 and 390's should go to mid 12's before running out of rpm.

 

[spedly]

Hope so. I do my own gears so If I have to do a swap or 2 to get it righ tno big deal. I ordered the tires now I have to find somewhere with the wheels in stock that doesn't want a arm and a leg. Then swap converters tand I'll be ready for the track again

 

[RandTx]

Probably not going get this completed till next week sometime.
Here's a few more teaser pics of the progress:
Oh an I did finally notice they are 390-40-17's not 45's duh!

These are stock 9" SST rims I had widened to 10" taking the offset from the stock +3/4" to + 1 1/4. That results in 1 inch clearance between the inner sidewall and the springs.
The wheel well liners stepped out portion will have to be trimmed out a bit to clear the tire but that should be no problem. The 390's o the widened wheel stick out a smidge less than the 305's do on the stock rims.

 

[RandTx]

Hey just wanted to say thinks again to John and M&H.

The M&H 390's ROCK. :rock:
They served me well last weekend in some very difficult track conditions, and that played a significant role in my winning that day.