I am running a fiberglass spring also and after the bolts that came with it caused it to rub the tires I switched to a 10" bolt and then had to cut about a good inch off of the bolt after it was all done.

 

O man... would love to see some picks of the TRW spring cut shorter... did you re-drill the holes further in also? did you grind them or???

but to the OP... I currently have the TRW on a 79 with stock 15's and had to grind just the lip of the steel that protrudes out... <1/4" then even in hard turns no rub... but it is very close...

O, and I am dropped about 2" and want to go 1" more

 

Why is it o that many of the aftermarket springs are too firm.
The PO replaced the rearspring in my, don't no the brand; and it sits too high as well. I haven't replaced the bolt with longer ones yet as I'm a bit reluctant to do so.

Anyone here who would know the consequences, or possibility, in removing one of the leaf's in order to get that rear back low where it belongs?

BR
Lars

 

Wow I just replaced my spring yesterday with a TRW #340 rate, rear sits a little high. Seams like I might have opened a can of worms. Hope I don't regret this choice!

 

I got a new shorter main leaf from Guldstrand and removed 3 of the original leafs to make it sit lower so I wouldn't have to use longer bolts.

No problems and it rides the way I want it to.

 

I feel like it's time to chime in here. I have been considering a change to a monoleaf and started another thread about which brand to choose. After reviewing VBP, Hyperco and ZIP, it seems these products are very similar and I have made the following observations from reading threads and the various opinions and issues on monoleafs in general. Flame away!

1. All monoleaf product literature I have seen across the board states " restores factory ride height"!

2. Most forum members believe factory ride height is too high, so they try and modify it with longer bolts. This compresses the spring it seems, which flattens it out and extends the horizontal span. Then you end up with the issue the OP submitted.

3. I will make an assumption here that using longer bolts reduces spring travel and increases spring rate....similar to cutting coils from coil springs? Any opinions on this?

So it seems to me the manufactures need to get with the times and offer various different spring arc that adjust ride height without the need for longer bolts to lower the car. This seems to be the source of the issue. Buying a new spring for $300+ dollars and having to buy different bolts and then grind off pieces of the spring and washer is not a solution to me.

After reading this thread I think I am leaning towards
going with a factory 7Leaf.

peace

 

You could always order a shortened spring. Get a 1/2" off each end.

On another note, I wouldn't let the end of the spring bolt go below the lip of the wheel. If your tire blows out, your rear end could be next.

 

Hope you can see this picture. I didn't move the hole although if I did this again I would remove the metal plates, grind the end of the spring till it has enough clearance then reinstall the plates and redrill the hole to match. I have more clearance than needed as I used to run a 16" wheel, now run 17's with 4 3/4 backspace. This car is only raced and it has been this way for 10 years, no problems.

 

noonie, did you actually removed some of the leafs, in such a way that you are driving with less leafs?
This is what I have in mind, but is curious how this will affect the spring rate.

BR
Lars

 

Yes I removed some and it drives very well.
I'll try to find some pics when I get home tonite.

 

Compressing the spring does extend it out horizontally, but longer bolts do not compress the spring more.

Longer bolts have no effect on spring travel or spring rate.

 

Huh? That makes no sense! For the Spring to extend horizontally it HAS to be compressed, at least a little!

Except for the fact the longer bolts compress the spring, which reduces overall travel at least a little

I also am interested in Noonie's solution.

 

I think you need to look at the pictures again to see how the longer or shorter bolts work.

 

Here are some pics of the Gulstrand lower leaf. It's 3/4" shorter each end. Original was too close with the stock alloys and BF Goodrich 255 60 tires.
Thicker than stock spring.



Less arch than original. This shows the difference in length when it is flatter as discussed in several earlier posts. It makes quite a difference.
The flatter Gulstrand is actually 1 1/2" shorter than the spring above it.



The head of the new center bolt had to be ground to recess into the centering hole, so as not to poke a hole in the diff.



I made a plate to reinforce tha original that bends easily. It also served as a spacer, so that the original mount bolts could be used along with a couple of the old springs cut for spacers. It can be changed back to oem easily.



Mounted to the diff.



You can count the leafs. (Leaves doesn't sound right)
6" bolts were used and poly cushions cut to half thickness on a lathe.
My intent was to end up with about 1 to 1 1/4" gap between the top of the tire and the fender lip.
The ride is firm and it will not bottom out on the bumpers, but we probably have the best roads in the country down here too.
The shocks are full hydraulic Konis, that are neutral in any position, unlike the gas shocks.
Don't know what the spring rate is, but the ride is firm, the travel is minimal and the cornering is great. My wife doesn't even complain, but it may be too firm for some.

 

Try to look at it this way. The car "hangs" from the T/A's via the spring and bolts. The bolt length affects the frame height ONLY. They act as "hangers," and nothing else per sey.

 

Finishing up my resto: Have placed a new, 7 leaf spring in the back with 8" bolts. Left is 29 3/16" and Right is 29 5/8". AIM states a ride height of 27.03". Very little gas is in the tank and the car has never seen the street to allow any settling. Many opinions in previous posts in this thread: should I go with the 10" bolts (if so, does anyone know the size and thread count)....should I drive it a while and see if it will settle out? Thanks for the help.

 

I was actually going to try using longer bolts as well because my ride height is a bit high as well but I cant seem to locate grade 8 1/2-13 x 10" bolts.

If you dont mind me asking, where did you pick those up?

 

The 10 inch bolts can be had from VBP and are listed as C4 rear lowering bolts. They work perfectly for C3s. Just watch the wheel-tire clearance.

 

I had installed VBP offset T/A's and rear rims with 5 1/2 inch backspace. When I put the spring in I had 3/8 clearance (17" rims). Uncomfortable feeling about it, I called Gary at VBP to ask if it would be OK for me to shorten the spring. As the end already has holes, and shortening it would require either slotting or re-drilling new holes(depending on how much I would shorten) the end of the spring would be weakened. The uncomfortable feeling was back. His response suprised me, "Just bring me yours and we'll custom make you one, the most I would go is 3/4"shorter each side". I went 1/2" shorter each side and problem solved. By the way he charged $0 for the custom spring. I was able to drop and pick up the springs myself so you may have to pay shipping (which would only be fair) To end this novel, 3 cheers to VBP for customer service.

 

On a different note. Take a look at the cushion under the spring. Might want to try seating the cushion in the spring cup as it is installed now or flipping it and put the flat side of the cushion against the washer and the rounded edge side in the spring cup washer.