Conference napalm::musclecars

    I have a question.I am now building another Z28 .It has tops.I want
    to run it at the street weenies next year.It will also be streetable
    I want to run it in the high 12's with out nitrous(it WILL)
    If I use sub frame connectors Will that lessen the chance of the
    twistage and having the t's leak .Any suggestions would be great.
    I already purchased the car. at 3000.00 it would s^ck to wreck
    this car.

    Yes !!! Connecting the subframes will help stop it from twisting!!
     The problem is finding the material and the route to connect it!!
    My brother in law had a Nova that he did it to. He used some square
    stock cut the ends at an angle,and miged it to the under carrige.
    It worked pretty good pain in the @$$.!!!
    
    There should be an easier way to do it!!!!!!!!!!!!!
    Mike.
    

    I installed subframe connectors in my 79 Camaro. I bought them from
    Competition Engineering for about $80. They wern't too difficult to
    install and they seemed to stop alot of the rattles the car used to have.
    
    They have both bolt in and weld in types. I installed the bolt in type
    but had them welded in at a later date.
    
    Mark

     I have a few questions around leaf spring type suspensions for
    the quater mile .1 I am thinking of using offset spring hangers
    with wheel tubs and offset rims .2 does anyone know of an aftermarket
    manufacture of rearched  Leaf springs.I hear this type set up used to
    or perhaps is still used in super stock classes and is good for running
    in the high 10's low 11's. Also performance wise v.s. dollar wise what
    is more cost effective  that set up or a 4 link set up .I have been 
    racing with my uncle for a while ,but he is no longer with us. So what
    I am left with is a big block camaro with est 675hp mediocore
    suspension .I know I should be able to do better than 12.20's 
    Thank for your help in advance .Val who needs a lesson in suspension
    tuning.BIG time!!!

    A more viable alternative and a fairly cheap one would be to go with
    what is called a "leaf-link" which was developed by Chrysler and Don
    Carlton in the early Pro Stock days. It involves a bar which goes from
    a front pivot point above the leaf to a pivot point on the rear end.
    Used in conjunction with an aluminum spring eye bushing, you
    effectively end up with a 4-link where the spring serves dual duty as
    both the spring and the lower bar.
    Four-bar fabrication and tuning is a real science and is better suited
    to a light car. Besides the tuning aspect they are very expensive since
    they use so many spherical joints. A relatively heavy car like the
    Camaro (can't be too light if you're running 12s) would do well with
    a ladder bar set-up. They're easier to construct and fit to the frame,
    are easier to adjust and cheaper to maintain. A 4-link offers more
    flexibility if the car is street driven.
    Your best bet is to go and look under other race cars. The majority of
    low-buck racers will be using ladder bars and if you ask them why, 9
    out of ten will tell you it's to save weight over leafs. If you talk to
    Chrysler racers, this is the only reason because the super stock
    springs work AS GOOD AS any other suspension on anything but a Pro car,
    they just weigh more.
    
    Stan

   I HAVE A QUESTION.  DOES ANYONE KNOW WHERE I CAN GET THE
   ORIGINAL STYLE SWAY BAR BUSHINGS FOR A 69 CORONET R/T?
   THIS STYLE BUSHING IS NOT THE STANDARD U-SHAPED VERSION
   USED ON VEHICLES AFTER 69, BUT IS ONE THAT SITS AT THE
   OUTSIDE EDGE OF THE K-FRAME CROSS MEMBER. I HAVE TRIED
   MOST OF THE AFTER-MARKET PLACES [YEAR-ONE, NAPA, ADDCO]
   BUT WITH NO LUCK. CHRYSLER HAS DISCONTINUED THIS PART.


   THANKS
    MIKE

    
    This should be reposted to the suspension topic.
    However, you might try Mitchell motors, Imperial motors
    or (I think) Ted Stevens.  All of these vendors specialize
    in good used Mopar stuff and might be your best bet. All
    of these vendors are discussed elsewhere in the file, exactly 
    where escapes me though.
    
    Good luck,
    
    Tom

    Forget replacing these as they aren't made and were never made to be
    replaced (don't ask me why). Seems they were supposed to be part of the
    complete sway bar assembly ONLY.
    
    There is a viable solution however. 
    
    Just pick up the April '92 issue (on your newstands now), turn to page
    16 and VOILA! there's your answer.
    
    Good luck,
    Stan

Solid streetable improvements for Late model Mustangs are harder to come by
then magazines would have you believe.  Often the best modifications consist of
optimizing things you already have; correct tire pressure would be one 
example.  Ignition timing would be another.  Let me ramble on about some
effective chassis modifications I've come across.  Keep in mind that I lean
heavily  towards little or no sacrifice in vehicle drivability and comfort. 
I've tried radical and not so radical modifications and rarely do they meet my
threshold of what is streetable.

SWAY BAR removal:  Those of the know will have undoubtedly read in countless
	magazine articles that the removal of the front sway bar will aid in
	weight transfer during hard launches.  Reports vary, but one might
	get the impression that this is an effective street modification with
	great value at the drag strip.  This is simply not true.  Even with
	chassis stiffening - such as strut tower brace, g-load brace, and 
	subframe connectors.  Body roll becomes extraordinary without the front
	sway bar.  After removing the front sway bar, I found myself at the
	cornering limit at what I consider commuter exit ramp speeds - above the
	speed limit, but not yet interesting.  Frankly, the whole experience 
	gave me the willies, and has since caused me to raise an eyebrow when
	I meet a person who has been driving without a front sway bar
        "forever".

	At the dragstrip, my 60 foot times didn't improve.  I believe they
	would have, given some practice, but the loss of the sway bar couldn't
	make up for a sloppy launch.  This is for street radial tires, smooth
	yet aggressive start while slipping the clutch; NOT the traditional
	clutch dump you might do with real drag slicks.    
                   
	BTW, the front sway bar is 1.31" in diameter and weighs about 25 lbs.
	The rear sway bar is 0.79" and about 10 lbs.  The general consensus
	seems to be leaving the rear sway bar in place.  The idea being that
	this helps plant the left and right side with equal loads.  

URETHANE BUSHINGS:
	Urethane bushings seems to be a hot item lately.  Especially the 
	black graphite impregnated ones - supposed to be less squeaky.  I've
	recently replaced the rear upper control arm bushings with urethane
	jobs I got from Just Suspension (Fairfield, NJ).  Currently I'm using
	Southside Machine Co. lift bars for lower control arms.
                         
	So far, the urethane bushings are quiet, and have *dramatically* 
	increased roll stiffness.  The bushings provide better feedback on
	acceleration by reducing squat and maintaining proper suspension 
	geometry.  There was a slight increase in road noise; but its of a 
	type that I don't find objectionable.  Essentially the noise sounds
	like tire noise, and provides comforting feedback.

	This is a keeper modification.  The car feels like I've doubled the
	sway bar size, but it isn't any harsher over bumps. For reference, I
	had stock bushings on the axle carrier, and Ford Motorsport upper
	control arms (M-5500-A) which have stiffer bushings then stock - though
	not as stiff as aftermarket urethane.

	LUBRICATE the bushings with suspension bushing lubricant, not 
	white lithium.  White lithium grease washes away within a couple
	of thousand miles.  The suspension bushing lubricant is generally
	synthetic grease with Teflon and has the consistency of chewing gum.
	It really works!  

CHASSIS STIFFENING:
	As soon as possible, you should install subframe connectors on your
	Mustang 5.0.  The increased chassis stiffness makes the whole car
	perform better, and quieter.  Same goes for the Strut tower brace.  
	After installing the strut tower brace, several front end squeaks and
	groans disappeared.  The resulting stiffness doesn't increase ride
	harshness.  I believe its because the unibody is taken out of
	the suspension system, and the springs and shocks can do their job
	more effectively.  Whatever the case, stiffening the chassis provides
	better ride quality, and improves handling dramatically.  
                                                                
        After installing new cylinder heads on I test drove the car for 
        a week without	the strut tower brace - mostly out of convenience, but
        also as	an experiment on its value.  The squeaks and groans reappeared.
        Installed the strut tower brace and they became history.

Eric

    Re -.1 good info Eric.
         
         I would also add that urethane bushings, heavier than stock
    front and rear sway bars, good gas shocks, and the addition of a 
    Monto Carlo bar (stone age for strut tie bar) greatly improved the 
    handling of my '71 Stang when I owned it.
    
             Dean

After 2 years of increasingly worsening rear axle slack and clunk, I think I 
finally may have located the culprit.  The spot welds that hold the rear
subframe to the floorpan have failed.  The dimples pulled right through the
floor leaving a stress cracked holes in the floorpan!  

Originally I thought the drivers side was the only thing affected.  I riveted
the subframe back to the floor, and the ride got really weird.  It felt better
in some conditions, and much worse in others.  That clued me in that there was
more damage.  I pulled the rear seat and insulation to discover that every
spot weld I could see had failed.  Telltale red dust (rust flakes) around each
weld is a good indicator that this problem has existed for awhile.  Both sides.

Integral to the rear subframes is the forward mounting anchor for the lower
control arms.  This would account for the axle moving around.

Now thats powershifting!: -) 

Please Mad Weldor, could you fasten my triobody back into a unibody.  I can't
race this thing with a clear conscience until its whole again.

Eric

    Eric,
    Sure..inbetween my trips to N.H,Vt,N.Y.,& Canada..over the next two months.
    
    TMW
    
    this is our busy time of the year....
    

While they seem to hold up fine with easy driving, I found that if you really
try, it only takes 1320 feet and 3 shifts to extract rivets from the subframe.

Eric

    Who said anything about Epoxy? 
    
    :-)
    
    
    TMW

Actually, the rivets and glue was more of a diagnostic aid then a fix.  I was
looking for a change the the backlash condition.  I found that there was
a dramatic improvement when everything was glued together :-).

Maybe it felt too good, because I immediately headed up to New England Dragway.
I made 2 runs - a no-traction-Some-guy-in-a-black-vette-roasted-me 14.2 ET run,
and a decent-but-damaging 13.56 ET run.  I'm seeing someone after work today
about getting the torque boxes fixed properly.

Eric

So whats holding the rear axle in place?...other than gravity:-)


R

And gravity.  These are the things that "fox" suspensions are made of.

I have three questions to throw out:

What and where might I find the right sheet metal for subframe
reinforcement and fabrication?  :-).  Can aluminum be MIG welded to the 
steel floorpan?  

Lately, it seems my friends and relatives address me with sighs, head nodding,  
and  gazes of deep concern.  Why is this?

Eric

    ....because we all know that your creativity and desire for speed,
    matched with a MIG welder is going to be a whole new era for us to get
    used to...just when we thought we had you figured!
    
    Just weld the damn axle tubes to the sub-frame and get it over with!
    
    /tb/ (I want to be there when the front wheels come off the ground!)

    Eric,
    Alum. and steel just don't mix! There are applications that can be
    joined, but not in this case.
    Did you use the Avdel rivits to attach the reinforcment channels? I
    believe the Greg Dwyer did this on his convt. We were going to weld
    them in be he felt that it was strong enough.
    
    TMW

I bought a MIG welder through the Sears Catalog.  Its a 110V light duty unit
for sheet metal - Automotive stuff.  I quickly rediscovered that welding
is difficult.  An art involving finesse, experience, and a knowledge.  Unarmed
with these qualities I made a 30-minute welding job last approximately 2 weeks.
:-) X 3.   However, I thoroughly enjoyed myself.  

Here is a list of nifty welding phrases I learned:  Out of position welding,  
slag, short arc,  contact tip, nozzle, shielding gas, anti-spatter spray, 
burn-through, stringer bead, weave, lap weld, and fillet joint. :-)

Jim, I used regular 1/8" steel pop-rivets I got from an industrial hardware
store.  I don't know that an avdel rivet is.

Eric

    Hi Eric,
     How much was the welder? How thick a piece of metal can you weld?
    I figure I can start preparing the Chief Accountant for my XMAS present
    now.
                                                               John M.
    
         

The weldor with a starter kit - gloves, tip cleaners, chipping hammer/brush, 
soapstone marker, angle magnet - came to about $475 total.  You'll also need
to locate a small inert gas tank for the 75% argon 25% carbon dioxide sheilding
gas.  Not all that cheap but I'm not sorry I bought it.  You can weld up to
3/16" metal with one pass.  Thicker metal with multiple passes.  It handles
0.024" and 0.030" solid welding wire, and 0.030", 0.035", and 0.045" flux-cored
self-shielding wire.  

The real beauty of the thing is the ability to weld *thin* sheet metal with
minimal affect on the high strength steel unibody structural members.  I was
welding 0.030" (22-gauge?) sheet metal.  With  good success after a little
practice - course this was after burning through my wheel wells and starting
to cry. :-).

Eric

    Hell, Burnthru is'nt anything to cry about.....when you hit a fuel line
    that'a  different subject....
    Sounds like you guys are gonna make me have to close the FF. (Scott
    please don't read this....you don't need a MIG!)
    
    Eric, sounds like you got a good start. Avdel rivets are what we use
    to install the upright rails on the cabs we build here in WFO. Strong
    as hell.
       
    TMW

Hi

I have a few questions around frame design for muscle cars.  If you have
a car with a big brute of an engine (>400hp) what things should consider
in the design of a frame?

What kind of tubing is better, round tube or square?

What kind of designed works best to handle the power of the engine
(ie. latter or something else?)

Where are the main stress points in the frame and where should it be 
re-enforced?

Is independant suspension better?

Thanks,
Dave.

    Dave,
    
    The type of tubing is not as important as the design of the chassis. If
    what you are takling about is a street car then some sort of unibody
    with rubber suspention isolation is prefered because of noise
    isolation. Round tubing cars can be built lower to the ground and tend
    to be more flexible. Square tubing tends to be stiffer and heaver.
    There are 2 types of tubing used for chassis fabrication, mild steel
    and chrome moly. Moly is stronger and lighter but costs more, is
    difficult to weld and cut. Mild steel is heaver and easy to weld.
    
    But, if what you are talking about is a race car.... then several
    factors must be taken into account. What horsepower will be produced? A
    2000 HP blown alcohol Pro Mod car needs a flexible chassis to absorb
    the shock produced by that much hp. A 9.90 Super Gas car needs a stiff
    chassis to transmit the torque quickly to the ground for quick reaction
    times. 
    
    Street suspension has to allow for twisting and noise isolation. Race
    suspensions must be positive and withstand severe shock and torque. 
    
    Bottom line is that chassis are designed to do a specific job. I what
    you want is a good upgrade for a street muscle car then weld in a set
    of frame connectors. If you want a race car then buy a kit from one of
    the chassis builders.
    
    my $.02
    
    db
    

Thanks for the response.

The questions came up when I was looking at a couple of kit cars.  There
are a lot of different frame designs used and I was curious as to which
ones were better.

What if you have a fiberglass body.  Does that make a difference in the type
of frame?  How about the way the body is attached to the frame?  

Let say for an engine of >400 hp, for the street.

Thanks again,
Dave.

P.S.  Anyone want to tell me if independant suspension is better or worse?

I've had a positive experience dealing with Addco, the sway bar manufacturer.
I'm installing one of thier rear sway bar kits on a 76 Camaro, and the hangers
used to go from the frame to the bar were several inches too short.  I called
them, and they made up better, more solid hangers of the specified length, 
and included all the bolts, and shipped them to me at no charge.
Matt

    
     I'm getting ready to rebuild the front suspensions in a 67 Dodge and a
    54 Chevy and have ordered catalogs from Just Suspensions and Performance
    Suspension Tech. Does any body have any experiance with these outfits
    or have any suggestions on other places to contact should I need any
    really hard to find parts.
     
     TC
    
    

    
    Ordered a PST Polygraphite kit for my `69 Cougar.  A few nits:
    
    1. No instructions, packing list, nothing.  Just a big box full of
       parts.  Luckily I recognized them all...
    
    2. For Ford products, they ship a stock lower control arm assembly with
       a rubber bushing.  It's up to you to drive out the rubber bushing
       and press in the poly bushing.  Again, no mention of this in the
       kit, and no instructions.  This one was a definate PITA....
    
    Tom