Was wondering, would a 1-inch front and rear wheel hub extension be
advisable for a c3 -1980 roadster ? The result would be the tires
jutting out an inch more on either side in the rear giving the car a
meaner look and (I assume) improving handling.
Would it be advisable ?
I'm not sure anyone can answer your question. Adding a hub extension
changes the geometry designed into the car by cantilevering the wheel an
inch beyond it's normal position, which will add stress to the wheel
bearings and spindles; it will also change the rear wheel alignment a
tad. For those reasons it's probably NOT "advisable"... now, whether the
added stress is enough to cause serious issues/failures is not easily
answered except by engineering calculations or extensive testing,
neither of which has been done by Chevy. I doubt anything catastrophic
will happen, other than that you may need to change the wheel bearings
sooner than you normally would. I doubt any improvement in handling
would be enough to notice.
ok.. but it does give the car a mean ass look !
I would never really push an old C3 really hard anyways.. a 30 year old
car should not have to prove anything... just drive around and age
gracefully (poetry in motion, so to speak)
I tried jacking it up this weekend and loosening the wheels and pulling
them an inch outward and then standing back to survey.
Damn it looked nice... So its settled then, in go the extenders .
Another addition would be extruding the flares over the wheel wells a
bit to meet the wheel extension.
This may seem like a wierd thing to do, but it makes people turn around
on the street. (if done properly)
Believe me, I have seen a car like this in the bay area.. it looks like
a killer shark !
Speaking of a Killer Shark
otherwise setting a narrow tire out wider only makes it look sad. My
guess is that those that turn around might be thinking the opposite of
what you think they are.
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I love that car! BUT I would change the wheels to period correct,
old Vettes just don't fit with Billet Wheels. And I think he blew it putting
that crankcase evacuation system on the collectors...... They don't do
squat below say 6000rpm.... Plus they aren't installed at an angle into
so I doubt they would create much vacuum at all, even over 6000rpm.
I absolutely agree, using stock wheels and tires with wheels spacers
would be cheezy IMO
as soon as you caught a 3/4 or rear view. But you know me, never replace
stock wheels and tire
without going bigger on the back, as big as you can stuff in there. But
that's just the way old hot
rodders from the Halcyon Days think. LOLOLOL
Huh.......... good catch. I got the zoomed pic of the engine and can
barely see the fuel logs.
He must have rubber hose or something over the sensor wires......
Still... maybe mount on the inside, but I guess you might have to notch
the rocker area..
Yes, you can cause problems. What are you trying for, the ricer look?
Skinny tires a foot outside the car?
First, the front end is dependent on where the tires sit as to rubbing and
hitting. The stock wheel is 8"x15" with 4-3/4" backspacing. With a
255/60-15 tire, the inner fender required trimming on '79 and earlier and
not sure about '80 and up. The factory trimmed those optioned with the
255/60-15 in '78 and not sure if they trimmed some, all, or none in '79.
Placing that same 255/60-15 on an aluminum wheel 8"x15" with a 3-1/2
backspacing (much safer than spacers) means that it rubs when turning in the
fenderwell at the back.
On the rear tires, this places the tire 1/2 to 1 inch outside the fender
which gets things chipped and dirty if you are driving and not just sitting
Spacers are bad on the studs, placing much greater stress than designed.
Corvette uses a 7/16 stud stock. In road racing, C3s during the '70s and
'80s used longer and thicker studs to prevent loss of wheels. Typically the
5/8" x 3" Moroso studs where used. It is generally recommended in racing
that NO spacers be used, however, they are not banned, but tech will usually
shoot you down as unsafe for any over 1/4 inch.
Mid America Enterprises (and others I believe) used an engineered
spacer/adapter to mount C4 wheels to the C2 and C3 cars. HOWEVER, these
spacers where necessary to fill the extra backspacing of the C4 wheel, so
the basic geometry of where the tire patch center was did not change. These
were also a high-tech aluminum alloy designed for strength and used to bolt
to the hub and then the wheel to the adapter, not merely a spacer.
So much for just the strength issue, now to design and safety.
Go to a BMW drivers school, one where they spend a day in class showing BMW
design videos and driving techniques, not just a "show up at the track and
You will find that BMW has researched the suspension geometry in much depth
before many manufacturers ever discovered that life existed beyond 1/4 mile
The location of the center of contact of the tire patch is very important to
safety and handling. It is hard to show without drawings, but imagine a line
from the upper pivot point to the lower pivot point. In the case of the
1980 Corvette, upper ball joint to the lower ball joint. Now extend that
line to the ground. This point is the ideal pivot on the ground. The
further outside or inside of that point a tire patch center is, the more
force a tire exerts on the car to turn left or right. In normal driving,
the left tire balances the pull of the right tire, however they are
constantly fighting. The further the center is from the point, the more they
fight. Add poor adhesion (water, oil, sand, snow, etc.) and you suddenly
have a car veering off the direction you wanted, i.e., ditch, oncoming
Have a flat, and you have a violent pull to one side. This is the very
problem that Ford had with the flat tires on the Explorers. They were
designed for a tall tire and so when it went flat suddenly (blowout), the
tire "moved" the contact point further from the ideal pivot point and there
was a violent pull that took the driver by surprise and, combined with the
high center of gravity, flipped them.
The Corvette, being much lower, will not suffer that flip, but you could
find yourself suddenly off the road or into oncoming traffic.
1. Spacers over 1/4 inch are a very bad idea.
2. Corvette does not have excessive fender room to accommodate offset tires.
3. A wider tire and wheel combo, with proper backspacing and offset, with
achieve the look you want and remain safe.
4. Wider tires and wheels will put a strain on the suspension, and the weak
point is the studs. Enjoy changing the rear ones. :-)
"LOLOL Get with the times man!! 13in dia w/3 in spacers....that was in
the Vanilla Ice days!
Now it's 24 in diameter and 6 in wide ultra cheezy wagon wheels.
HAHA.. 20 inch blades on the Impalaaa !!! (words of a Hip-Hop song i
heard on the radio)
insight into whats cool these days.
Honda civics with 19inch rims !!!
Escalades with Ox-cart like chrome wheels !!!
Chevy Silverados with flames paintjob and 13inch wheels (2 inches
ground clearance... WTF ???)
20 inch spinners on a Toyota Camrys.
:-) tsk tsk tsk !!!
I don't know whether to laugh or cry.
Thanks 'Tom in Missouri'.. That was the kind of input I needed.
Good thing I havent bought the spacers yet. I will stick to 1/4th as
My new wheels and tires are a little wider than stock already. (atleast
the new set i bought are, the car is still sitting on the original
Ricers ! yuck ! wouldn't go near those flimsy little japanese pieces of
sh** with a 10ft. pole. I honestly dont understand them anyways, waster
of money and mostly bad styling (especially those horrific spoilers I
see on WRXs and Civics...)
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