EM corvette front spring rate?

doitover · #1 (**permalink**) 12-04-2002, 03:20 PM

I need a lighter spring for my Corvette suspended EM Cobra. The ride height is too high and my body weight on the front won't deflect it. From talking to them in the past they apparently received some 600 lb springs and I probably have one of those.

The question is, what rate do I want? The engine is a Chevy LT1.
Any opinions?

Thanks,
Doitover

scottj · #2 (**permalink**) 12-04-2002, 03:43 PM

I diditover with coil-overs front and rear. Ride height problems aren't uncommon with the Vette Brakes springs and neither VB nor EM knew what rate I had.
Scott

doitover · #3 (**permalink**) 12-04-2002, 03:54 PM

Scott,

Who's coilover's did you get for the front? Did you have to modify the frame? I actually like the idea of the monoleaf but the lack of ride height control and just lack of information bothers me. In the past though I've been told there aren't any coil overs that fit without reworking the frame?

Thanks,
doitover

mr bruce · #4 (**permalink**) 12-04-2002, 04:25 PM

www.flex-a-form.com

scottj · #5 (**permalink**) 12-04-2002, 05:06 PM

doitover,
I have 13.4" Proshocks w/4" stroke and 2-1/2" ID springs. Yes the frame is modified, Brett built the frame with upper mounts that are to drawings that I supplied. Because I wanted heims I needed to make the top mount 1" taller. I also have a clevis for the lower mount that bolts to the stock location on the control arm. If you want to use the stock style upper mount you could just reinforce the top plate, although I know of guys that didn't do this. QA-1 and Proshocks make shocks that will bolt right in using the lower clevis. COBRA427 has a set of the QA-1's without frame mods, you might try a PM to him for specifics.

I'll put some pics in my gallery you can check out.

Scott

SpitzSpitz · #6 (**permalink**) 12-04-2002, 06:26 PM

doitover you can adjust the ride height of the front with the EM corvette spring. the bolts the ends of the springs simply need to be adjusted down, if yours are like mine you are already adjusted all of the way down I believe the bolts are 8 inches long. simply purchase new bolts two inches longer and adjust down until desired height.

Even with this the ide is harsh, I sayw a coil over kit on this site one time that did not need frame mods, if anyone remembers that string, that would helpful.

If you need more specifics let me know, I will make measurments or send pictures, whatever will help.

The Spitz

scottj · #7 (**permalink**) 12-04-2002, 06:44 PM

Spitz,
You're thinking of the rear and that works well since the rear rate is already good. The one thing to watch, both front and rear is that you don't lower it so much that the lower control arms go past parallel getting you into an undesirable positive camber gain situation. There are simple mods you can do in the rear that will improve the camber gain.
Scott

SpitzSpitz · #8 (**permalink**) 12-04-2002, 07:01 PM

scottj darn it your right, got my head up, oh never mind. any advice on the coil over conversion.

Spitz

BT SNAKE · #9 (**permalink**) 12-04-2002, 07:24 PM

Spitz is right, I too have the front coil over shocks and I did my
modification 14 yrs ago. I took the lower control arms and had
an aluminium U bracket welded into the pocket. I then drilled
a hole off the side of that pocket big enough to insert a large
allen headed bolt throught the bracket and the new shock. I used 12" total lengh Eagle one shocks. The top mounting
bracket is too close to the frame and it has to be extended outward about a 1/2". That's it. Then you can throw that fiber spring as far as you can.

It was one of the best mods I ever did to the suspension. It's easily adjustable with a spanner for
sring rate or turn the little knob for 15 position dampening.

Hertsh

scottj · #10 (**permalink**) 12-04-2002, 08:09 PM

Spitz,
For the front the clevis is $60.00/pair and a 13" extended length shock then bolts right as long as the top mounts are welded on straight. EM's tend to have some shift of the upper mount during welding which can then cause interference with the spring. You may or may not have to relocate the hole for the top shock mount. Ed B. aka COBRA427 used the stock-type upper mount and had no problem with his conversion while I did. I used 350#, 8" springs with an aluminum sm blk.

There are a couple of different ways to do the rear, both being more involved and require fabricated lower mounts and different trailing arms to gain clearance for the coilover. The trailing arms are a good idea even if you dont go with coilovers since the stock EM arms allow toe changes under hard acceleration out of corners. On the street it's not that big of a deal but on the track it makes for erratic handling... not good with a 90" WB.

If anyone is interested in more specifics PM me and I'll give you my number.

Scott

SpitzSpitz · #11 (**permalink**) 12-05-2002, 07:21 AM

Scott, thanks very much for the info, I may want more detailed info in the spring.

Thanks again.
Spitz

doitover · #12 (**permalink**) 12-07-2002, 09:15 AM

Thanks all, we had a little power outage here and I'm just now getting to log in. I'm thinking about finishing the car the way it is and putting this decision off until I know what the weight on the front is. The coil overs are sounding pretty good. I'll file this away until then. Thanks,