< WBoyd1959:
> I'm new to the group, so if this has been covered ad nauseum, I apologize
in
> advance.
>
> I have a an early 67 1600; put on 15" Panasport rims with Toyo 195X 50
> series tires. Front end sits way to high off of tires and needs lowering.
> Rode in a car with Comp springs and it was extremely stiff; too much for
me.
> Need to lower about 1 3/4" or so. Maybe as much as 2".
>
> Some other Roadster owners have cut off one coil from the fronts, or heat
on
> end and collapse one coil. Is either method OK, or is their a better way.
I
> heard there is a kit out there somewhere that's made for 510's and Z's
that
> you install with new springs and allows for adjustment by a threaded
sleeve
> both up and down.
In addition to the comments from Tom and Todd I'll add the following. Since
the car wasn't designed with 50 series tires, using them or any wheel/tire
combo that's much smaller in diameter than OEM may not "look" right, but
that doest mean the suspension needs to be altered to achieve what's
essentially a cosmetic fix.. Still, if you want to do this don't lower the
car by heating the springs, cut them. If you heat the springs, there's no
way you can control the results nor are you likely to end up with the same
rates on both springs. It just ain't gonna happen in the real world. You can
cut them using a cut off wheel in either an air or electric die grinder, or
with a Dremel tool which will probably take longer, but it can be done. Same
idea if you're tempted to cut them with a torch, don't. Cut them, or have
them cut.
For street use I think you'll regret trying to drop the front two inches, at
least all at once. Aside from the big increase in spring rate caused by
shortening the spring enough to lower the car two inches, you're loosing
that two inches of suspension travel, too (already pointed out), and you're
almost certainly going to mess up your suspension geometry, since the
geometry is designed around the stock ride height.
What do I mean? Well, for a number of reasons the wheel doesn't move
straight up and down with the wheel/tire combo always perpendicular to the
road. The angle changes constantly as the suspension moves up and down. When
you alter the static (at rest) ride height of the car by lowering it, at
least without also relocating the suspension attachment points, you may not
have enough alignment adjustment available to compensate. Traditionally
you'll end up with way too much negative camber, with the top of the tire
tilted in toward the car's centerline.
I know it'll be a hassle to do, but I'd suggest cutting off no more than a
half a coil at a time and then reassembling the suspension to evaluate the
changes. You can always cut more off, but it a real PITA trying to super
glue springs back together. ;>) If you're going to test drive the car after
a change, then you really need to get it aligned, every time, first. Or, you
could just roll it back and forth a few times to get the suspension to
settle in before deciding to take more off, or not.
Finally don't get sucked in to slamming the car just because it looks
"cool". I see so many otherwise very nice late model import sedans and
coupes that almost drag on the pavement and that have incredibly obvious
misalignment problems. They've got to be uncomfortable and at the least a
handful to drive, if not actually dangerous.
One of the biggest mistakes folks make on 510's is excessive lowering in the
rear which, unless you go to the not small expense of relocating the
suspension pickup points, causes a toe out condition in back. This creates a
very loose handling condition which has caught many by surprise big time,
often with very unfortunate results. If you look at the BRE 2.5 Trans-Am
cars so prominently covered in a number of magazines the past couple of
months, you'll notice that they actually sit a bit higher in back than in
front. There's good reason for this. The ride height was adjusted for the
best handling, not just for looks.
Lowering vehicles the right way is the reason that a number of companies
offer dropped spindle setups for newer vehicles, particularly trucks. Moving
the wheel spindle up lowers the vehicle while leaving the suspension in it's
as designed position. Then the main thing you need to worry about is speed
bumps and such tearing up your (usually) custom bodywork and paint.
Bottom line, take your time and approach your goal slowly. If you don't have
them already, I'd recommend buying a decent air compressor (two
cylinder/belt drive/20 gallon tank or larger) along with a fair set of air
tools. You should be able to get both from Costco or Sam's for around $400
or $500. The tool quality won't be the best, but should be good enough for
the weekend hobbyist. Take the word of this "old guy" (ask Gordon if you
want/ need that explained), these tools will make work go much faster,
probably safer and are well worth to investment.
FWIW,
Ron
Ronnie Day
ronday@attbi.com
Ronnie_day@acd.org
Arlington, Texas
***********************
'71 510 2-dr (Prepared Class Autocrosser)
'73 510 2-dr (Street Toy)
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