67 Monoleaf Spring Question
 

So, I measured the free arch on both monoleafs. One is 7 inches and the other is 5 1/2 inches.

Are there any specs other than free arch?

I read that the monoleafs should have a free arch of 6 1/4 inches. Is that correct for a 67 SS/RS 350 Muncie 4 speed and 12 bolt posi rearend with the fold down rear seat?

Also should I have my current springs recurved or replace them? Anybody had experience with recurved leafs?

Thanks...

It appears I can get a new set of monoleaf springs locally for about the same cost as recurving the old ones. So, off to pick up a set of those today.

Hope that works out for you. It has been my expearance that the guys that re-arch springs and better then factory. Base on post I have seen new mono leaf springs are a real crap shoot. When the springs are re- arched the tech will normally want to see the car on its existing springs so they can estimate the correct change. I believe they can also work from a book but you will just be getting stock spec springs which does not take into account options. I remember one large customer the spring guy wanted the car with the guy in it to get the rear leafs right. Then I did the finally alignment with him in the car. The guy was 6.5 and 385 lbs and he said it was the first time he had a car that did not pull to the left.

With most springs free length (or in this case height) does not mean much. Because of slight variation in the metal and the heat treat process the machine set the arch under the estimated load of the car. The free length is not a factor as long as the spring can be installed. As you may know in the first few days that the car is driven the springs will settle which changed free length greatly.

Well, I stopped at the local muscle car shop only to find out their pricing on their website is wrong. It's like double what they show on their website. So, now back to considering recurve on the old springs. The car is on a rotisserie so not able to take it in. I think I will talk to the spring manufacturer again about the recurve. They had said $150 for recurve (per spring I am sure). The manufacturer is Pohl Spring in Spokane Washington and they have been around for nearly 100 years doing all kinds of springs.

From my research, it appears the free arch on the 67 coupe mono leafs is 6 1/4 inches whereas the 67 convertible mono leafs is 8 inches. They both seem to have the same spring rate at 126lbs. Can anyone confirm this and, if so, why is the free arch higher for the convertible? Is the convertible heavier in the rear than the coupe?

The vert is heavier

Just find someone like me who is swapping monos for multileaf
You can have mine after I get them out in the spring
Then measure all 4 and use the best two

Any chance you are in Washington State?

I just had a long technical talk with the folks at Pohl Spring in Spokane Washington. Pohl has been manufacturing leaf and coil springs since 1915 per their website. They will do a full heat process to recurve the springs which in my mind is the right way to do it (as opposed to cold process). They show the spec for free arch for the 67 Camaro monoleaf as 6 1/2 inches. I can drop the springs off when they open on one morning and pick them up the next day after noon. The cost is $150 per spring so I am going to go this route.

Sorry, near SLC