Best way to adjust rear coil overs for proper height on my SPF

[elmariachi]

I learned a lot about my car while working through setting up alignment, ride height and suspension. Measuring the corner weight is an integral part of this process and made a difference in how my car handles. No point in owning one of these cars and not making every effort to set it up right. I have also found that understanding your weight distribution helps you understand why the car handles like it does.

[Jerry Clayton]

If you take into consideration that many of these cars have 600 hp and weigh aprox 2400 lbs, its easy to see that on a perfectly balanced 50/50 f/r weight that you have 1/2 hp per lb of weight on the tire----now what is harder to see is that if unbalanced, its not that a little hp transfers to the lite side , but most of the hp as soon as the wheel loses a little traction, all the hp goes up in smoke---

Complicate this into the braking situation---front rear bias, anti-dive, maybe some cornering---

It should become abundantly clear that corner weights being pretty close instead of just pretty is a necessity in a car like these

[akfish]

Here's some information I found when setting up my car.

''There is a poor man's corner weighting method that involves using a floor jack on center with the front and back of the car. As you slowly raise the front end (for example), one tire will clear the surface faster than the other. So to put more weight on that tire (so that both rise off the floor at the same time), you have to "jack up" the opposite corner (i.e. crank more tension on the spring). Of course, you're supposed to do this with driver's weight in the front seat, too.

You do this back and forth (front to rear) until you achieve as near balance as you can. It doesn't account for fender gaps and overall stance (which may end up not being what you are after). But what you will achieve is a very close corner weighting without using scales.''

[D-CEL]

Patrick,
Not mad, irritated, but that is your goal. So maybe I should adopt the DR385 “shtick” and interject it into all of your ERA/FE posts.

Jerry,
Not so much, I left the brake bias set for dry day with too much rear. Operator error.
But no worries on the CWs, I have an (old) set of Longacres in the shop. Ill make sure it’s good to go before I’m out on the track.
I think you guys are adding complexity and cost to what he is asking. Remember, Pman is looking for an aesthetic RH adjustment, not curing a handling malady or reducing lap times. To me it’s not a necessity, let alone critical at this stage in his game.
Few push these cars to the place where setting CW is beneficial and fewer are willing to sacrifice the change in stance (read “look”) to get optimum handling.
I will say “corner weighting” will not make a street tired Cobra hook 600 hp, I don’t care what you do!~
I’m all for setting and adjusting, tinkering and playing. It’s what I live for. I don’t care (much) what it looks like, so long as it works, but that’s me.
Everybody owns these cars for different reasons. Very few seem interested in going fast, be it on the track or the street. Most are cruiser types. They love talking about their dyno-sheets and the wax they use, but have little interest in spring rates, brake bias or ackerman, The mechanics are lost on the vast majority. But that’s ok, they love the cars for what they are to them.


Jason

[Tony Ripepi]

Hello All,


Just helped one of the guys here in the BACC, with a ten year old SPF, change out the AVO shocks to QA1's on all four corners. When it came time to adjust the ride height and set the shocks we simply went with the recommendations included with the shocks measured from the center of the wheel to the lip. We also changed the rear mounting bracket so with all of the changes Pat drove it for a couple of hundred miles then we reset the adjustment on the shocks and the ride height. Look at the QA1 site for recommendations, SCOF is great and possibly something from Bilstein.

This is a street only car and driven for pleasure, the four corner weighting may be a nice to do as opposed to a need to do for street driving comfort and handling. The four wheel alignment really does add improvement to handling.

As for the wrench, it has been pointed out earlier in this thread what you need, I found that once the weight was off of the spring on the lift it could be turned by hand on the QA1's. I am not familiar with the Bilstein set up but, it can't be that difficult. I do have an old Moroso spanner wrench that has worked on all of the shocks for my SPF, Shelby, GT40 and Daytona Coupe and worked on the QA1's.

Best Regards,

Tony R.

[Jerry Clayton]

So you were just picking at Patrick???

[D-CEL]

Jerry,

LOL picking on Patrick? You must be joking. Calling him out for talking crap about SPF owners and offering nothing to the OP with regards to his question?

Absolutely!


JASON

[Pman1961]

D-Cel hit nail on the head. I'm adjusting the height primarly for aethestics because the car has a squatting appearance. I've had my car since September of 2008 and been very busy the past few years with little time to drive much less personalize. This year I transplanted the 351w 385hp crate motor with a KCR 445 611hp, change TKO 500 to a TKO 600 4617, modified sidepipes by Perf Engr, radiator and oil cooler guards, Kirkham billet aluminum brake and clutch reseviors, quick jacks and pipes to black from silver, leather moto lita wheel replaces the wood wheel with other items planned for the future. My driving is mostly through the suburbs with a dart down the highway prior to coming home. I do not intend to track my car as insurance does not allow (however, I hear tracks may offer some temporary insurance). I do not have a vehicle nor a trailer to do the track thing anyways. I've always been a straight line hot rodder. I do not or will not test the limits of this car cornering. I'm sure it may sound boring to some. Yeah, I've got more horsepower than me and most of you will ever need but it is the look the sound the feel that I was and am going for....menacing like the original Cobras. For me, I like the smile the car brings to my face every time I fire her up. Loud, shakes, stinks........ahhhhhhhhhhhh. Gotta go fire her up!

[Jerry Clayton]

I guess I'm melloing out a little bit as I've always sorta thought that any person who would have a car like this and put 600 hp in it but didn't want to fine tune the entire package to the best overal vehicle was nothing but a poser and I'm starting to think that way again when I read threads such as this---nothing personal guys, but really????

[dont]

I doubt that the majority of the cars here have been corner weighted or have a 50/50 balance ratio. So the majority are all posers.

[akfish]

Calling people names,for having fun with there car,which is different than the way you see fit is just lame.

[DanEC]

OK - no arguing that knowing the corner weights of your car is of interest. But, for education purposes - what exactly are you doing with this information, especially for a strictly steet cruiser? I'm not going to shift the battery front to rear or side to side. And I'm not going to add lead to one side or drill holes in the panels or gain/lose weight myself to even things up. Brake balance is going to be a trial and error thing during break in. I'm going to set the chassis up according to the manual and evenly side to side. I'm not disagreeing - just curious what I would do with this information.

[patrickt]

Originally Posted by DanEC

I'm not disagreeing - just curious what I would do with this information.

It's not what you do with information, it's how you adjust the coilovers so that you have the proper ride height while having as close to 50/50 cross-weight distribution with your body weight behind the wheel. Your car will do everything better if you set it up this way and it costs nothing to do it.

[Jerry Clayton]

It isn't a matter of what you would do with the information---
its just the correct way to set up a car--why even have coil overs if you aren't going to use them correctly???

[dont]

The corner weight that they are talking about here is done with the coil-over springs. You try to get even weight on the rear tires and the front tires by raising or lowering the coil-over to add or subtract weight from a particular tire. The problem is with out a properly balanced car from the start you wind up with a lopsided look because of uneven tire gaps.

[Silverback51]

A 50/50 balance is not necessarly the best set up on a Cobra due to the tire size difference from front to rear.

Now you can compensate up to a point with tire pressures, sway bar sizes and adjustments, and spring rates.

You have to consider all factors, not just corner balance.

It's like saying a 650 CFM carburator is the right one for all 302 to 350 cubic inch motors. It's just not true. To many other factors that can affect it.

[Pman1961]

Akfish...as they say around here 'you are my kinda people'. I have started threads seeking advice on many occasions. Such as how to remove the engine and transmission (as a unit or separate), crankcase ventilation, clutch recommendations, etc. Then somewhere down the line the thread goes off in another direction. Example..advice for modifying my side pipes. There were Firefly, Full Throttle, Classic Chamber, Performance Engineering comments. Positive comments on all, more some than others until I elected to go with Performance Engineering and posted my decision then all the negatives came out. I became stupid. End result I was happy with my decision as they did a great job and achieved what I was seeking. I will not push my car cause the street is not the place to do it and quite frankly do not wish to end up in a ditch. My car makes me happy for what it is....looks great, sounds great and when I want to feel my butt pressed into the seats...just crack the throttle!!!

[patrickt]

Originally Posted by Silverback51

A 50/50 balance is not necessarly the best set up on a Cobra due to the tire size difference from front to rear.

Crossweight. Unless you're only turning in one direction you want a 50% crossweight regardless of your tire sizes.

[ACademic]

Originally Posted by Pman1961

I'm adjusting the height primarly for aethestics because the car has a squatting appearance.

For what it's worth to you, that slight reverse rake/look is actually what most Cobra owners are after! The wheel arches in the front actually make the car look a little taller at that point in the body. Having a slight air gap in the front wheel well and little to none in the back is the look, and if you research originals in several published books and journals you will see the same thing. I'm not certain if that is the way they came originally, or you now have a bunch of sagging originals that people want to keep as they came to them. But simply raising up the azz end will actually make the tail lighter under heavy braking and you may actually worsen the balance. And I know from experience that sticking to the "factory" settings of 27" (ground to wheel lip) is actually too high.

Again, personal preferences and enjoy your car!

[Jerry Clayton]

But what you aren't getting is that if your off with the proper set up, you can easily end up in the ditch--dodging some kid chasing a ball into the street, dodging an animal, motorcycle, texting driver-----

These cars aren't BMW, Mersedes or even Chrysler 300s---- they are like playing Russian Roulette with 5 rounds in the magazine and the street is the most unpredictable place to be with them--on track is much more predictable.

But mechanical and maintenance work needs to be done properly and according to a standard that is fitting to the vehicle---any car under 3000 lbs , with 600 hp-----