FMJ leaf springs

Did some research on here, and elsewhere. I am 95% sure but figured id ask just to be sure. FMJ's share the same length leaf springs correct? Calvert lists caltracs for an f body, so if they share leaf spring size then they will fit on my Mirada. Also anyone install these? Do they have a shock plate? or do I reuse mine?

Same part numbers for fmj in my parts book.
I have a complete set from an F coupe, ex race car that I parted.
Even saved the calvert front shocks and aluminum spring eye inserts.
They have a shock plate much like the non-iso rears use.
Using them eliminates the iso stuff as well as the rubber spring bushings.

Thanks for the reply. When you say complete set, what all do you have? Did the car have their monoleafs on it? Also what about rear shocks?

F body Deconstructor Jim said:

Same part numbers for fmj in my parts book.
I have a complete set from an F coupe, ex race car that I parted.
Even saved the calvert front shocks and aluminum spring eye inserts.
They have a shock plate much like the non-iso rears use.
Using them eliminates the iso stuff as well as the rubber spring bushings.

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JIM- do you still have the Caltrac setup?? Your inbox is FULL. Please message me, I need the setup for my Volare.

Jim hasn't been on this site for a couple years. Not sure what happened but, he just vanished suddenly.
Also, sorry but I completely forgot something. Check your PM.

Im sure you know the FMJ caltrack/mono spring setup is one of the best for the mopars as far as instant center goes since it has the long front spring segment.

Yes thanks. My friend has a set for a Camaro with 26" front. Use these with ARE 105 1.5" shorter hangers and bingo! Have to make a driveshaft anyway

At times I really read things backwards so I might be 180 off on what I wrote below.


Im a little confused with the Use these with ARE 105 1.5" shorter hangers part as are you moving the axle forward? If you use the fmj calvert monos why the need to move the spring forward? Are you moving the axle forward? If so your headlong into the pinch point far past what even a 275/60 would fit when if done well you can get a true 10.5W and although ive never tried it (a 325 Radial) a 10.5W specs out real close to a 325 tire.


If you unbolt the caltrack mono springs there is a pre drilled hole to move the axle one inch as well, one can move the axle back one inch and gain that inch in the tightest spot that impacts a larger dia. tire and width as well. Im referring to the inner front lower portion of the wheel well area.
Also if its a non important type car you can cut 3 slots (a 1/8 thick wide diamond tile wheel makes a perfect cut) in the seam that holds the lower portion of the inner fender to the fender well and gently use a mallet to roll it inward. It can be done gently enough as not even to crack or chip the oem paint off.

the camaro spring is longer by 2" in the front segment to the locating pin, thus use a 1.5" shorter bracket to put the actual axle 1/2" rearward of the stock location.

Dad has a set on his 408 powered Diplomat Coupe. Retained the five leaf setup. With 275-60-15 Radial T/A it dropped the quarter time from 13.2 to 12.9. Made a huge different in how the car tracks from a dead stop. Instead of being squirrelly it launches nice and straight. This is on both a prepped track and on the street.

Only made a couple runs last year with them. Need to make some more adjustments and better tires.

My friend has a set for a Camaro with 26" front. Use these with ARE 105 1.5" shorter hangers and bingo! Have to make a driveshaft anyway

Im thinking you might check things really close before you purchase the ARE 105 hangers as they leave just enough room to hang a spring but several factors tell me its going to put the front pivot assembly of the cal track in a bind. But you could possibly trim a bit of the caltrack side plates.

Looking at the pic of the are 105, yes you can get a spring eye to fit but it looks close and the spring eye on the ct spring is pretty big.



Here are some pics with the oem spring hanger mount center at approx 2 3/4 and when adjusted out properly is very close to being in a bind, so taking 1.5 inches off that I think might be a stretch.



During the off season I back off all the tension. The next two pics show it backed off alot, the second pic shows the line where the front pivot assembly sits when adjusted and you can see its pretty close to a binding situation as is.

So im wondering what things will present themselves if it were all moved up 1.5 inches.




Looking more at the are 105 vs the are 109 F hanger you can see the big difference in room.





Ive a street handling setup with a no arch spring a shorter CT segment bar. And a track setup with the CT setup as delivered.


You can see again in the pic where the CT pivot assembly sits at rest and im still thinking if it were 1.5 inches up it would bind.

So it might be worth checking





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Well I had to find out, so I went out and adjusted it just to the spring with no load on the bar and it looks to be dead on 1.5 inches, so if your ARE 105 is a real 1.5 shorter then a oem F. Hmmmm. Check, check, check.





But then again, I read into everything backwards, so your case might be a non issue, but maybe worth checking.

I was just wondering if I might of used a non f front hanger so I went and looked at one of my "I will restore one day" f-s and it is a oem hanger im using and you can also see how the oval eyelet fills the hanger and although not relevant here it looks like the shortest hanger that will work with a oem spring.

Thanks for all the info and come to find out, the Camaro spring is only 1" longer in front and 2" shorter overall. So the axle will get moved back 1" using the stock hanger and we'll make some longer rear shackles. Best of both worlds!

One thing you need to be aware of is the rear spring hanger eye in the frame should be 1" farther forward than the spring eye with the car weight on the spring.

Another thing to keep in mind, one inch back will make shocks with a big diameter like the rancho 5 ways if mounted in the oem spot. A small diameter al. body single or double adjust will get by. But you can make a filler where your shock would go and run a longer bolt or stud and attach on the back side of the mount bracket. And if your going to get serious about racing, just plan on cutting that oem shock cross member out and weld in a proper bar to attach shocks to, one way or another either by you or the abuse its gonna come out.

the stock spring shackles sit vertical to the rear frame eye in the hanger.