Why no Magnum 500s on Hemi cars

[8WHEELER]

I have seen so many 66 Hemi Chargers, over the last 35 years with the Chrome magnum wheels, I assumed they came that way factory   

Good to know on the C-Body size, I have at least six sets of 68 Chrome Magnum's, and all are 14x5.5 so all b-body wheels.

And the only repop size available are 14x6. I have two sets of them.

Dan

[6bblgt]

And the only repop size available are 14x6. I have two sets of them.

reproduction wheels are available in many sizes, but not 14x5.5" if that's what you meant 

The "spinner" wheel cover was STANDARD on the '66 Charger.  No other cap/cover/wheel was FACTORY available.

[8WHEELER]

And the only repop size available are 14x6. I have two sets of them.

reproduction wheels are available in many sizes, but not 14x5.5" if that's what you meant 

The "spinner" wheel cover was STANDARD on the '66 Charger.  No other cap/cover/wheel was FACTORY available.

That is what I meant, I have many repop sets of 15x8's and 15x7's as well, having four of these cars, I have collected many
sets over the years, some look better with 15x8's, and the bone stock cars I keep stock. My 74 Dart Sport 360 has 15x7
magnum's, Most people think it looks better than the Rallys.

Dan

[charge69]

Well, I have all 5 original 15" steel wheels for my Charger and 4 new OEM wheel covers that also came on my Charger but, I am kinda fond of the "day 2" look and the Cragars with wider tires.

[odcics2]

Also, the 66-68 chrome Magnum's on mopar's, were offered at 14 x 5.5 only. So I think the width came into play somewhat for the 68 model year Hemi car.

The Ford Chrome Magnums were offered at 14 x 6 and 14 x 7, I believe the 14 x 7 started in 67 or 68.

Dan

No MAG wheels from Chrysler Corp. in '66.  The '67-'68 chrome "ROAD" wheel was 14x5.5" on b-bodies & 14x6.0" on c-bodies.  IT'S ALL ABOUT THE TIRE! There are many 1970 HEMI b-bodies that came from the factory with "ROAD" or "RALLYE" wheels that were 14x5.5" with F70-14 Goodyear POLYGLAS tires (in '68 the F70-14 was a much less capable tire - GOODYEAR SPEEDWAY)

Mustang did NOT have a 14x7.0" wheel until 1970 & it was NOT of the MAGNUM 500 design.

68-69 Hemi cars got a 15" wheel for oil pan clearance. In 70 the standard wheel for a hemi was a 14x6".   

[6bblgt]

68-69 Hemi cars got a 15" wheel for oil pan clearance.

if that was true  - Chrysler could've cranked the torsion bars up for the same effect (& what changed for '70 that this was no longer needed or desired)

In 70 the standard wheel for a hemi (b-body) was a 14x6".  

CORRECT!  ..... but if 14" W21 "RALLYE" or W23 "ROAD" wheels were ordered - the wheels were 14x5.5"

[ws23rt]

If the Od of an F70-14 is 26.6'' and F70-15 is 26.9" as FJMG said that would put the car .35" higher (or just a bit less than 3/8") with the 15" wheel.
The width of the rim would not change the diameter of the tire a relevant amount.

[6bblgt]

26.9-26.6=0.3" diameter

Coker Tire shows their reproduction Firestone WIDE OVAL tires as:
26.90"(F70-15) - 26.20" (F70-14) = 0.70"

Kelsey Tire shows their reproduction Goodyear SPEEDWAY tires as:
26.51"(F70-15) - 26.20" (F70-14) = 0.31"

Kelsey Tire shows their reproduction Goodyear POLYGLAS tires as:
27.09"(F70-15) - 26.45" (F70-14) = 0.54"

half that dimension would be raising the car from the centerline of the wheel (or the oil pan)

[ws23rt]

26.9-26.6=0.3" diameter

Coker Tire shows their reproduction Firestone WIDE OVAL tires as:
26.90"(F70-15) - 26.20" (F70-14) = 0.70"

Kelsey Tire shows their reproduction Goodyear SPEEDWAY tires as:
26.51"(F70-15) - 26.20" (F70-14) = 0.31"

Kelsey Tire shows their reproduction Goodyear POLYGLAS tires as:
27.09"(F70-15) - 26.45" (F70-14) = 0.54"

half that dimension would be raising the car from the centerline of the wheel (or the oil pan)

You are right--in the difference of 26.9 and 26.6.  I miss. typed the dia.  that FJMG wrote. ----He showed the F70-14 to be 26.2" dia.  OOps. That is what I meant to say.
My point is that the difference in height of the car is minimal and makes me wonder about the motive for giving the oil pan more room as being the reason for the rim size question.

[Mike DC]

     
The oil pan clearance isn't an issue when the tire is inflated and the suspension is at ride height.  But the factory had to build cars for the 100% real world. 


Imagine driving hard into a curb with both front wheels, like at full speed.  The tire sidewalls will compress fully.  At the same time, the front suspension will be bottoming-out against the rubber stops on the LCAs.  Now the front wheel rim height is the only thing holding the chassis off the pavement. 

With the Hemi oil pan/skid plate sticking down an inch farther than stock, running the bigger wheels was the least they could do.  Even with the 15's only half of that extra inch is on the bottom side of the rim.

[ws23rt]

   
The oil pan clearance isn't an issue when the tire is inflated and the suspension is at ride height.  But the factory had to build cars for the 100% real world.  


Imagine driving hard into a curb with both front wheels, like at full speed.  The tire sidewalls will compress fully.  At the same time, the front suspension will be bottoming-out against the rubber stops on the LCAs.  Now the front wheel rim height is the only thing holding the chassis off the pavement.  

With the Hemi oil pan/skid plate sticking down an inch farther than stock, running the bigger wheels was the least they could do.  Even with the 15's only half of that extra inch is on the bottom side of the rim.

The extra half of an inch on the bottom side of the rim is not what raises the car. It's the extra .35 in. on the bottom of the tire.

My only point about all this is that the wheel/rim diameter is not what determines the height of the car.  It's the tire dia. on that wheel.
With the F70-14 tire (26.2" dia.) the car is .35" closer to the ground than it is with a F70-15 tire.(26.9")

If the car had an 18" rim with a 26.2"dia tire it would not be 2" closer to the ground because of the rim size. It would be the same.
This of course discounts any difference in side wall flex between the two examples.

With the tires fully compressed as when hitting a curb their would be a slight difference. I wonder if this is what they had in mind when the decision was made about the rim size?

[Mike DC]

ith the tires fully compressed as when hitting a curb their would be a slight difference. I wonder if this is what they had in mind when the decision was made about the rim size?

That's my point.  If the rim itself gets 1" bigger then that holds the chassis another 1/2" farther off the pavement no matter what.  



We don't think about this stuff.  But the factory does.  Not only that, the whole undercarriage of the car is designed to minimize damage if the whole car gets forced over a curb.

Look at how the stock K-frame's leading edge is curved, and how that affects the side-view angle it presents a curb.  (The aftermarket never worries about this, do they?) 

Look at how the front edges of the rear subframe rails are sloped upwards to the floor.   

There are other things to hit under the chassis, exhaust, radiator support, etc.  But all that stuff is more "crushable" compared to the subframes & K-frame.