AMC suspension (looks like an early mustang)

[dusterbd13]

i know this may sound odd, but were doing an AMC spirit for a friend of mine. it'll be a daily driver, and also compete in the GRM 2008 challenge. presently, we've rebuilt the stock suspension, used poly bushings throughout, KYB shocks, 1 1/8 ADDCO front sway bar, 3/4 rear, eliminated the iso-clamp system, and lowered the rear of the car 2 inches over stock (three inch blocks, as the iso clamp was an inch). using 15X7 steel wheels with a 25 inch tall tire (havent gotten the tire size nailed down yet). stock brakes, stock steering, etc.
were trying to figure out what other changes to make a drastic improvement for cheap. id love to do stiffer springs, but all i can find are 5 1/2 diameter springs, and these are 6. and no one makes rear leaves,even stock ones. id put another leaf or two in it out of my old Dakota springs, but that would bring ride height up even more.
also looked at subframe connectors to increase rigidity, but i cant figure out how to make them.
weve reduced weight as much as possible on the front for a street car (no front bumper, no smog, no AC, relocating battery), and its going to be a 6 cyl car (if were far enough under budget, we'll do a 4.0 HO swap with a 258 crank for a stroker).

the long and the short of it, does anyone have any experience making these cars handle? if so, what else can we do to aid it for insanely cheap? can we use early mustang parts?
thanks
Michael

[dusterbd13]

no ideas?
anyone even ever considered an AMC?

[BRIAN]

There is a coil over front kit out there but you can easily fab your own.

[67bird]

I am no expert, but how similiar is the spirit frame to say an AMX? If it is close, have you tried researching what they did with them back in the day for trans am racing?

[dusterbd13]

well, there are no similarities between the early AMX cars (68-70) and the spirit. however, the late AMX 79-82 is the exact same body/chassis. basically a V-8 spirit. unfortunately, i cannot find any info on the late ones.
good idea, though.
Michael

[67bird]

First thing I would look at is eliminating the three inch lowering block. See if you have a good spring shop in the area, they can make springs for you. Then I would do some research on what rates they have avalible for the front and rear. Maybe use a v-8 spirit with AC spring, with a coil removed. Lastly, I would look at possibly getting adjustable shocks of some kind. You didn't mention if your KYB's were adjustable.

[4birdman]

Yeah, ditch that 3" rear block. I just wouldn't feel comfortable running that. Go with what 67bird said and have them rearch those springs for the drop.

[Beige]

They changed the suspension in all of the cars in 1970 to the ford style to get some anti-dive for racing.
So you can look into 1970 and later trans am AMC's for ideas.

http://www.amx-perience.com/TransAmRacing1971.htm
for example, shows some of the parts they used. Most of it looks like reworked stock parts.

http://www.amx-perience.com/amx-enterprises/AMXEntGymkhanaSuspension.htm
not much but they sell sway bars and shocks for later AMC's (bottom of the page)

Other than that, you can probably apply the early mustang tricks to the car, even though you won't be able to use the parts.

[dusterbd13]

hmm...
after looking at those links im half tempted to yank the front end again and box everything.
we may go with dearched/stiffened springs sometime soon, but for the initial shakedown well keep the blocks. theyre actually cast iron units off my old one ton ram. so im not worried about breaking them, just massive amounts of spring wrap.
as far as the rates go, with that one coil cut, the front end is incredibly stiff. i dont know if thats due to the KYB's, or what, but there is almost no gove. hopefully there is some travel in road conditions, and its not bound up.

what do you think about a home made montecarlo bar? we wouldnt be able to get it right between the shock towers due to master cylender and carb placement, so would it even be worth it?
also, if we rearch the springs, would there be any advantage in installing a panhard rod?
reason i dont want to go adjustable is because of cost and the fact that we scored the KYB's already at dirt cheap.

keep the suggestions coming
Michael

[67bird]

I know its not suspension related, but what rear does the car have? If if is the AMC 20 please upgrade the axle shafts. Support bars if the front probably wouldn't hurt. Also you didn't mention tranny. I would think this probably has a 904 or a derivative. If so may want to look at doing some stuff to it for durability standpoint. I wouldn't think you would need the panhard bar with leafs.