Moment center design

[drifttec101]

Has anyone measured or messed with the moment center location of our 2gn's?

[fixitmattman]

You'll probably be hard pressed to find more than a few people who even know what you're asking here, let alone actually taken the measurements.

While I've thought about it, I've yet to muster up enough ambition to actually go out and determine roll stiffness or even find the approximate static roll center. The roll stiffness is probably going to be more useful to you than the roll center location.

[drifttec101]

I was thinking maybe some autocross guys have messed around with this before. I'm not sure how much it could be tweaked with our cars anyways... you can't purchase control arms that aren't stock dimensions correct?

What really sparked my curiosity in the MC is that so many people here have lower their 2gn's, but god only knows what that does the the MC. I need front struts on my car because they are over 90,000 mi on the OEM (ouch). When I get new struts I might as well get lowering springs too ya know. I'm thinking H&R because they don't put the car on the ground. I just want a stiffer ride, but I don't want to screw with the geometry. If I could, I'd put stiffer springs on the car that didn't lower it, but I don't think anything like that exists.

If it does someone let me know.

[fixitmattman]

The roll center is the least of your problems when you drop this car. Just like any car, the closer you get the weight to the ground the better off you're going to be. The issue is the suspension geomtry goes to absolute shit when you lower the car much more about an inch an a half. At about 2 / 2.5 inches the front / rear lower links are about parallel to the ground at ride height. At that height and geometry you end up getting a camber curve that gives you positive camber gain. With a bit of math and custom fabrication you can fix that to give you a nicer camber curve, but it's not the easiest/cheapest thing to do and takes a bit of time. Then add the fun added by the bump steer change. Hence why I've had almost an entire suspension and front end sitting in my basement for a while. By the time I get around to it the neon will probably be in the junk yard.

Stiffer springs with only a mild drop would probably be the best.

[drifttec101]

Yeah stiff with a mild drop is ideal in my opinion. The only problem with that is the aftermarket almost ONLY caters to those who want to slam the thing on the ground. It's kind of funny actually.

I didn't even think about bump steer... that must go to hell when these things are lowered haha.

[occasional demons]

Not sure if they sell HD springs for the neon, but those would stiffen the ride. Not at my normal PC, or I would list the spring PN's for the various trim levels/exports. Dante may be able to get some spring rates on them, but I can't promise anything. That would be for him to answer. Even if there was an HD option, it would prolly give you lift anyways.

[drifttec101]

What do you mean by HD?

[Mopar_Korean]

HD=Heavy Duty.

I think what hes getting at is putting springs that were designed for a heavier neon (or another car) on a basic and lighter neon. This will result in a stiffer ride and a slight lift. You would have less weight on a spring making it harder to compress it.

Really the only real options are some coilovers or H&R springs, Eibach Pro springs and Blues, or you can call Performance Driven LLC and order some High Rates, X-High rates, or XX-High Rates. They have them for the 1st gen neons and 2nd gens as well.

http://www.performancedrivenllc.com/default.aspx

[drifttec101]

Wow what a great tip... that company is just minutes down the street from me!

[hansken_yo]

My personal recommendation for what you are looking for is ful-adjustable coilovers like, if not, BC coilovers (though they do not adjust caster). This is just one aspect of being able to control the geometry of the vehicle once lowering or leaving at normal height (who would want to do that)...

If you were to do this then you would also need to find a shop that can corner balance the car along with an alignment.

Pretty much with the coilovers (along with other modifications such as sway bars, tower strutbars) I've got my car balanced to a 63/37 weight ratio, with a 51% cross balance. I've set my Camber to -1.75*front and -1.25* rear and I've so far adjusted the dampeners to 8 clicks from hard.

My description of this setup has me handling corners pretty damn close to neutral leaning slightly towards understear (I really don't want my back end coming around). Problems I come across is being able to keep power down on the road when it becomes really bumpy streets giving me some mild skip.

There are some rear adjustable control arms available in the aftermarket, but I haven't found the need for that quite yet. I'm still researching how I can improve my setup but as of right now and my driving skill this works pretty damn good.

[drifttec101]

Yeah I'd love to have some coilovers but I was looking at the trade in value of my car and coilovers are actually worth about the same as my car is. So I can't really justify getting coilovers in my opinion.

Why do you run 51% cross weight? I would assume that keeping it neutral would be the best.

[neonslg09]

Then why do anything to your car?

[racer12306]

Then why do anything to your car?

[drifttec101]

Because my front struts are shot. I really need to replace them, and stiff springs feel good so I'm going to get some.

[racer12306]

Well, the only way you will ever be able to adjust anything related to suspension geometry is to spend the big bucks.

[drifttec101]

yeah exactly that's why I don't want to slam my car on the ground. That way I won't end up with awful suspension geometry that I can't adjust... get it?

[hansken_yo]

51% is the best that I can get for cross balance which is very good regardless. If I paid hourly at the shop they would get it to 50% but when they tell me that 49-51 is very good I'm not going to fret the difference and end up paying even more than I already do for an alignment.

Frank is right, if you want to be able to adjust the geometry of your car you are going to have to spend the cash. On top of that, the value of your car really shouldn't matter. What should matter (imho) is the value you get out of your car. If spending the cash for coilovers and other suspension parts increases how long you keep the car and enjoy the car and get what you want out of the car then there is value there.

[occasional demons]

What should matter (imho) is the value you get out of your car. If spending the cash for coilovers and other suspension parts increases how long you keep the car and enjoy the car and get what you want out of the car then there is value there.

If you are looking at it as an investment, $ wise, then stop now. New struts/springs/bearing plates/tophats, etc, to do it right/or complete, are going to be $600 plus.

[hul kogan]

...the value of your car really shouldn't matter. What should matter (imho) is the value you get out of your car.

Amen, well said.

If I looked at it this way, my car wouldn't have much done to it...if anything at all. I know many other people would be in the same boat, too.

[drifttec101]

I think everyone is missing my point here. I want a decent handling car, without investing a ton of money into it. A ton of money would be buying coilovers. I can avoid the doing that if I don't slam it on the ground. That way I still get a good handling car, and I don't have to worry about suspension geometry. Does that make sense?

[racer12306]

Just because you have coilovers doesn't mean that the car has to be slammed to the ground.

Like Occasional Demons said, struts/springs etc etc will add up to near what coilovers cost, you would be better off just getting the coilovers for the extra money.

[drifttec101]

I don't want the adjustability of coilovers... I want the car to remain very close to stock ride height in order to avoid the need adjust geometry design. Do you understand what I mean?

[racer12306]

Yes, I do but you can keep the same height with coilovers. You don't have to lower it.

[drifttec101]

Yes, and then I just spent $1200 ish. I can put some springs and front struts on for much less than that.

[hansken_yo]

Burn the car.

[drifttec101]

How would I get to school and what not then?

[Danteneon]

Has anyone measured or messed with the moment center location of our 2gn's?

When you first posted this, it seemed as though you were interested in an aspect of your car that not many people are aware of. That would lead me to belive that you were serious about supension performance. But looking through the rest of this thread it now seems like you want nothing more than a stock car with higher rate springs. OK then...

Get some OE quality struts and mounts, and stock SRT springs. That will give you a higher rate of spring, the front will be nearly the same height and the rear will drop slightly (appox 1/2"). No need to worry about moment center design.

[drifttec101]

I am interested in not screwing up my geometry. I do know a bunch about moment center, bump steer, camber change curve, ackerman effect etc. Since I understand what these things do I really feel bad screwing them up. That's why I want to keep stock parameters, but stiffen the ride. However, the aftermarket doesn't cater to people like me (I'm different).

SRT springs could do it... I was looking for a little stiffer, but that's certainly an option to consider. Thanks

[racer12306]

I think you are over-thinking this.

[hul kogan]

I think you are over-thinking this.

This.

Just snag a set of Tokico Blues (nice aftermarket struts of OEM quality/performance) and throw some SRT springs on them. Done...and you've accomplished your goal without spending too much.