>Well, I'd like you to know that I really appreciate your help and sharing
>your knowledge & experience.
Your welcome, but I was beginning to wonder how valuable it is. I haven't
kept
up with what's available or what the latest tricks are. I decided if I was
going to continue this thread then I needed
to be 'enhanced', so I made a couple of visits..........
>Maybe I could start with new rubber bushings and do something to them to
>harden them up a bit. What if I bought both rubber and poly bushings,
>turned down the poly ones on a lathe to say 1/2 of their original diameter,
>then bored out the rubber ones and inserted the poly ones inside? Is this
>an idiotic idea? Probably ;) What about just pounding some nails into
>them? ;)
I'm going to pretend I didn't see the first idea. :^)) So you know the old
hotrodder's nail trick huh? It works. I went to Super
Shops this morning and they said so many people wanted poly bushings, that
they
came in street and competition hardness now. Shock bushings, the whole nine
yards. The bad news is the street versions are almost as hard as the old
race versions. I'm guessing 5X
more than rubber based on an impromptu hammer test. Race versions are now
mostly metal. I drove a '67 Camaro
and a '94 Paseo with the polys and while definitely harsh, I could
live with them on the Paseo, but they do tend to emphasize any chassis
shortcomings. The Camaro creaked and groaned and felt like a Flexi-flyer
with overinflated tires compared to the Paseo. Since you have the chance,
make the chassis STIFF, so you can use the poly's.
This Camaro also had a nifty
rack 'n pinion setup made by Sweet Manufact. (616/344-2086) that may be just
the ticket. It appeared to have about the same turns lock to lock as the
Bricklin, 3-1/4?
Both cars had custom
progressive rising rate springs, 1" shorter than stock by Eibach Springs
(714/752-6700).
>> >Is a stiffer rear bar reducing understeer by: helping front traction,
>> >hurting rear traction, or both?
>>
>> It moves the polar moment of inertia forward (pivot point changes)
>slightly,
>> improving front/rear weight distribution.
>
>Forward or backwards? If the weight is biased to the front, moving the
>polar moment forward would make things worse, wouldn't it?
Forward and towards the loaded wheel. I gave a too simple definition to an
infinite number of points
along the roll axis in 4 pi (3D) space. This point has nothing to with the
center of gravity (CG), but concerns the transfer of body roll (sprung
weight) to a particular corner of the car as opposed to dynamic weight
transfer which occurs whenever you accelerate / decelerate. Still a too
simple answer to a complex interaction of forces.
>
>These guys have a shop that's primary purpose in life is a place for them
>to build cars that they race. They do a bit of fabrication for other
>people to try to pay the bills. I'll have an in-depth chat with them about
>the project. It will certainly help to be able to share the thoughts of
>somebody who knows a lot about the Brick.
What kind of cars do they race?
Just so there's no confusion, I've never modified one. What I have done is
compare it to what I know about Vettes and how similar the philosophies are.
Check into how much mods it would take to convert
to coil overs front and rear. They showed me a plethora of shock/spring
options. This would definitely be a quantum leap in suspension upgrades and
allows better options for hooking up all that HP. This afternoon I visited
my buddy Wayne, who does all the Panoz alignments for the factory and has
helped them with a redesign. It uses a modified version of the Thunderbird
IRS (I didn't even know the T'bird had IRS!). It can be modified for
perimeter style chassis mounting, a big plus. Panoz replaces the lower 'A'
arms with a tubular version that does away with the spring perch and adds
coilover mounting, but you could probably keep it ~stock for cost /
simplicity. Don (Panoz) arrived with two to align, so I got to drive one. It
handles like a go-cart with a relatively supple ride. He says after
alignment they are tested and average 1.08g on Road Atlanta's 200ft skidpad.
We discussed the Bricklin and we all agreed though that coilovers in front
with custom 'A' arms and the Lincoln rearend with coilovers, watts linkage
and swaybar was probably the best in terms of performance / cost ratio for a
daily driver. Also, the latest issue of Kit Car has an add from C.W.I.
(714/642-9807) listing several different IRS combo's including a custom
using a Ford 9" center ~$2000.
>I'm thinking that aluminum heads and intake, plus replacing the cast
>exhaust manifolds with headers should help me shave 50-70lbs off of the
>front. Is that a pipe dream or is it realistic?
S.S. said to expect ~ 35lb / head reduction, 25lb / manifold, 35lb / exhaust
or ~165lb.
>
>OK - how about at 100 mph ;) I wouldn't mind a car that pulls from 100
>twice as hard as my RX-7, as long as it could do it without getting
>sideways ;) I've heard that the SV-1's handling strength is straight-line
>stability... How well-behaved are they at triple-digit speeds?
The one thing Bricklin accidentally got right was the aero package.
Beginning at about 80 mph, downforce causes the car to squat. The faster you
go, the more it squats. This is why the car has cooling problems with the
original hood/firewall rubber seal in place. Heat can't properly escape
underneath the car, so must exit out the top which helps to increase
downforce. The bad part is that just like a ground effects race car at high
speed, if something unsettles the car in a corner, then it snaps away from
you. This happened to me on a 100+ mph on ramp blast, and while I caught it,
my passenger's reaction was, in Bill Cosby's words: "first you say it, then
you do it". A spoiler at the rear would help this some and also help to hook
up the tires above 70-75 mph.
>> That seems a bit different than your original stated goals. :^))
>
>Well... I guess you've got me there. ;) The truth is that I'd prefer a
>sports car over a muscle car. If the SV-1 is a diamond in the rough, then
>I wanted to get to work on polishing it. If it's always going to be a pig
>rutting in the mud, well, I guess I'll get my slop bucket ;)
If you could go the coil over route with the other mods discussed, I think
it would have real possibilities. It's never going to match the Mazda
without significantly lowering and moving rearward the CG, plus lowering the
roll center. Ultimately, tires would be the limiting factor. You just can't
put much rubber down without some serious wheelwell flares. BTW, Super Shops
recommended staying away from 35-40 series tires on older cars. Their
customer's experiences indicated that, unless the chassis was really rigid,
tire wear, handling at high speeds and ride harshness was unacceptable, and
in some cases, downright dangerous. Another thing would be to dump the V8
boat anchor in favor of an alum. V6 with dry sump to get it lower in the
car, with the oil pump / tank in the rear axle area. This would probably
help handling as much as all the other mods combined.
GM
|