Spring rates

[quickquarter]

Have any of you guy's got corner weights from your cars?
Interested in what a 428 4speed car weighs, and front to rear bias, please.
Or what spring rates do you have? Or have used?
Thanks.
May get this shellvalley car together, after the third owner.

[Terry Stapley]

I have not weighed the corners yet but the spring rates are:
Front 350 pounds
Rear 250 pounds

Set up for Small Block Ford engine!!

[quickquarter]

Thanks Terry,
But that is what concerns me, that sounds like a lot of spring.
Are your shocks and coilovers angled? If so, what angle from vertical. This may be part of the reason. How much compression are your spring getting loaded? at ride height.
Am still wondering what the total weight is, and at least a front axle wheight and a rear axle weight.
Anybody?
I am sure a softer spring in the front could be used when a sway bar in front, is in service.

[Tim Brewer]

Everybody's shocks are angled and so should yours. 350 / 250 is most common.
Tim

[quickquarter]

Tim and Terry, Thanks for the response.
Well, I don't want to start an argument here.
If your shocks are angled, then you are not getting a 250 lb spring rate from your 250 lb springs.
I contemplate reworking the 2 x 2 frame rails behind the rear axle, to one accommodate a steel can fuel cell, two to relocate upper shock mounts, about 2" further outboard. Replacement of shock mount on axle, and thus these rear shocks will be vertical, so actual spring rate will equate to actual load on axle. I kind of guessed that 150 rate spring should be adequate for the rear, "IF" there is adequate shock valving. That is why I want to know how much preload compression the springs have from free height to ride height, from someones use of a specific spring. I would like to be able to have control over 6" of shock travel, without losing spring travel.
So if someone has an FE motor in their snake, please weigh the axle loads for me.
One other thing I am doing, is building a lower "A" frame lower control arm, and junking the stock control arm and strut rod, from the must. II front suspension, for free suspension travel, no strut rod bind. Better steering stability. The upper coil over shock mount here will also be moved outboard as space allows.
Thanks for your input.
Gerald

[Tim Brewer]

Gerald,
We realize that for every degree of angle of your shock is canted, you lose a percent of spring rate. So, regardless of what the actual spring rate actually is, we just use say, 350 /250 as a basic starting point and then maybe hone in from there. Plus, there's not really a right or wrong spring rate either. You could use very light springs for a soft mushy ride, or more than double the rate for autocross. But you can't have both.The idea of canted shocks is that it gives more travel without having to use an extreemly long shock. Anytime a shock is canted it will always have more travel. A car with 6" of travel with near verticle shocks will yield a car that looks like one of those 4WD AMC cars from the 70's, I don't think that is what you're after is it? Cobras generally have around 2 or 3 inches of travel.
Good luck,
Tim

[stuartt]

I have just re sprung my DAX it had 375 front and 160 rears, now 450 front and 250 rear, ride is much better could probably have been a little stiffer in the rear.

[mgilbert]

greetings, what about running a little lighter spring with adjustable shocks just an idea. i have 289c.i. 375 springs, adjustable shocks QA1. MUCH improved ride. like i say just something to think about. see ya Mark G.

[quickquarter]

Thanks,
Tim, the travel will be about 2 - 3 in compression ond 3 - 4 in rebound.
And no it wont use all of that, and it won't look like a, well whatever those were.
And the intent is to use adjustable shocks to stiffen the ride, and slow the spring reaction down. That is what shocks do, not the springs.
May end up with 17 or 18 inch wheels with a 40 or 45 series tire, Z rated of course. As there will be no sidewall deflection now, the spring will become much more important to ride and handling.
I think with the proper shock setting and valving, and the proper shock oil. I can make it ride as stiff as the 250/450 setup, if I wanted to.

Mark G. What have you got on the rears?

Variable rate valving also will come into play here.

I want to thank everyone for their input, please share more.
Again, Thanks
Gerald

[mgilbert]

hello again, just stock mustang crud. trying to decide if to use coilovers or go with weight jackers on lowers do you know what i mean. just finished putting on tube control arms and QA1 coilovers only took it around block a couple times, but seems to be much better on front end . nextwinter rear end. i would like to get brakes more confortable also. see ya later Mark G.

[sideoiler10]

I have a Shell Valley Cobra running a '66 427 sideoiler. I have not had it weighed, either all of it or the corners, but I have been told by Shell Valley that with the FE engine, 1 3/8" input toploader, and 9" rearend their cars weigh in at 2500 to 2600 pounds.

About a year ago I replaced the shocks and coilovers with QA1's all around to improve handling and ride performance. I have also found that the coilovers have very little shock travel on this type suspension (the springs are only 7" long uncompressed). When I replaced the rears I followed Shell Valley's recommendations and went with 250s. I wish now I had went a little heavier as the rear feels a little bit soft if a passenger is in the car. That only occurs if you hit a dip in the road at speed. Lets face it, if someone wants a nice smooth ride they aren't going to be considering a Cobra in the first place. They are supposed to be brutally uncompfortable.

Good luck, Bob