Marcos Maniacs

Hi Maniacs,
Some recent postings were discussing the various choices between wire 
wheels,aluminum wheels, various diameter wheels and tires.  While I 
certainly don't have the definitive last word on this subject, I do 
have some real life numbers from my car.  My car, a 1966 Marcos 1800 
had Dayton 14 X 6 inch, 60 spoke, wire wheels in the rear (with 215/60 
Yokohama AVS tires)and 13 X 5.5 inch wheels in the front (185/60 
Yokohama AVS tires).  I have converted the car to Panasport aluminum 
wheels which are 13 X 7 inch wheels with 205/60 Koyo RA1 tires all 
around.  So first, note the differences since the comparison isn't 
exactly "apples for apples".  The new rims are wider than the previous 
rims.  In the rear the new rims are 1 inch wider.  In the front the 
new rims are 1 1/2 inches wider.  The original tires in the rear were 
slightly wider and of a larger diameter (215/60/14 vs. 205/60/13).  
The tires in the front were narrower but the same diameter (185/60/13 
vs. 205/60/13). Now the numbers.  The rear wheel assemblies (meaning 
the wheels, tires, and everything needed to mount them) the numbers 
come out like this.  Wire wheels with knockoffs and 215/60/14 Yokohama 
tires weigh 47.4 pounds EACH.  The new Panasport wheels with lugnuts 
etc. and 205/60/13 Koyo tires weigh 29.2 pounds EACH.  So the new 
aluminum wheel assemblies in the rear weigh 18.2 pounds LESS for EACH 
rear wheel.  So the total weight savings for the two rear wheels is 
36.4 pounds which is a lot!
The numbers for the front are 39.0 pounds for the original wire wheel  
and  29.2 pounds for the new Panasport wheel with a difference of 9.8 
pounds per wheel or 19.6 pounds for the front end.  In addition, I 
changed the front hubs from steel to aluminum.  The original steel 
version weighed 5.4 pounds and the new aluminum hubs weigh 3.6 pounds 
for a savings of 1.8 pounds per hub or 3.6 pounds for the front end.  
So the new wheels/tires/hubs saved 11.6 pounds per front wheel or 23.2 
pounds for the front end of the car, which again, is a lot!  Total 
weight savings for the entire car is 59.6 pounds of unsprung weight. 
It is also interesting to note how much heavier the 14 inch Wire 
wheels (with 215/60 tires) is than the 13 inch Wire wheels (with 
185/60 tires).  The 14 inch Wire wheels(and tires) weigh 47.4 pounds 
and the 13 inch Wire wheels (and tires) weigh 39.0 pounds, a 
difference of 8.4 pounds per wheel.   Part of extra weight is in the 
wider tires and some of the extra weight is in the wider rims but I 
think we can safely say that the larger rims weigh more... quite a bit 
more. So the numbers are not small and for the best handling you want 
the numbers (unsprung weight) to be small.  If you want the best 
looking wheels then the wire wheels, in my opinion, win easily.  By 
the way, I changed to the aluminum hubs in the front to get the same 
bolt pattern (4 1/4")on the front as is on the rear.  The fact that 
the hubs weighed less was a bonus.  I could further reduce the 
unsprung weight in the front by changing the front brakes to lighter 
units which are available. 
I just received my new springs for the front and the rear today (merry 
Christmas Mike) so once I have installed those I will post a report.
By the way, has anyone else noticed the new changes at the Marcos 
Maniac web site?  What do you think about the changes?
Mike Denman
1966 Marcos 1800
Chassis # 4079

The original tires in the rear were 
> slightly wider and of a larger diameter (215/60/14 vs. 205/60/13).  
> The tires in the front were narrower but the same diameter 
(185/60/13 
> vs. 205/60/13). 

Mike,

The 205/60/13 tires have a diameter of 22.7" vs. the 185/60/13 
diameter of 21.7".  Am I wrong or did I miss something??  Seems like 
you gain an inch in height in the front and lose 1.5" of height in 
the rear.

My 195/70/HR13 tires with original wheels (cast aluminum I suppose)
weigh in at 32lbs. mounted, balanced, and lug nuts included.

Where are the pics of this new setup??

Don Lattimer
#3M5759 V6
Willits, CA

Hi Don,
Yes the diameters of the new tires are a little different from the old 
tires.  The shorter rear tires have put my acceleration back into the 
"warp speed" category even with the 3.77 rear end.  According to the 
calucations the difference in rpms at 60 mph was like 160 rpms more 
(or something like that).  At any rate, the acceleration is noticably 
quicker.  The handling is improved but I am in the process of "pricing 
out" a Quaife limited slip rear end to help keep the rear end "hooked 
up".  I am still playing around with the spring rates in the front 
(225 lb)and in the rear (150 lb.).  I am also going to change the 
anti-sway bar diameter from .690 (approximate) to .875. So, I still 
have a ways to go before the suspension is fully sorted out.
I'll post some pictures when I am a little further along in the 
progess.
Mike Denman
1966 Marcos 1800
Chassis #4079

--- In MarcosManiacs@y..., "mcaqmd" <donlattimer@p...> wrote:

>   The original tires in the rear were 
> > slightly wider and of a larger diameter (215/60/14 vs. 205/60/13).  
> > The tires in the front were narrower but the same diameter 
> (185/60/13 
> > vs. 205/60/13). 
> 
> Mike,
> 
> The 205/60/13 tires have a diameter of 22.7" vs. the 185/60/13 
> diameter of 21.7".  Am I wrong or did I miss something??  Seems like 
> you gain an inch in height in the front and lose 1.5" of height in 
> the rear.
> 
> My 195/70/HR13 tires with original wheels (cast aluminum I suppose)
> weigh in at 32lbs. mounted, balanced, and lug nuts included.
> 
> Where are the pics of this new setup??
> 
> Don Lattimer
> #3M5759 V6
> Willits, CA