Only 335 Rear Stiffness on Tein Flex's? (need stiffer)

[allshow_2g]

That rating sounds close to Tein's S-Tech springs stiffness level. But I hear people with 400 or 500 rating springs in the rear?

My rear end is really heavy, posted about this a while ago. But anyway decided to go with coilovers now, but after seeing the ratings for the rear, I don't see where the advantage would be.

This is what I have in my rear, I dunno how heavy it is, but perhaps someone can tell from the equipment and give a good estimate on what I need.

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Thanks in advance!

 

[PaulPDX]

You can get higher rate springs from Tein or any Tein dealer.

Who did your audio install? looks good. I'm Portland too btw.

 

[allshow_2g]

Originally posted by PaulPDX
You can get higher rate springs from Tein or any Tein dealer.

Who did your audio install? looks good. I'm Portland too btw.

How do I do that exactly? I don't know what to ask for or who or where exactly hehe.

Audio was done by Car Toys, I actually bought the car from the original owner with the system. So I don't know exactly what all is inside there, like the enclourse, but I'm guessing total is probably at least a couple hundred pounds.

Hey Paul sounds like a Russian name... it would be funny if you were someone I know or know someone that knows you...

 

[PaulPDX]

Originally posted by allshow_2g
How do I do that exactly? I don't know what to ask for or who or where exactly hehe.

Huh? call or email Tein (tein.com). You can get the springs from them or they can refer you to an authorized dealer. They may even be able to suggest a spring rate.

I'd estimate the gear you've got to be around 200 lb.

Hey Paul sounds like a Russian name... it would be funny if you were someone I know or know someone that knows you...

Nope... not Russian.

 

[jtmcinder]

There are two ways to approach this issue. One has you focus on the weight to spring ratio. So, if the rear corners of a 2G usually carry about 650# each and TEIN thinks that you should have 335s (i.e., 6 kg), then they are suggesting about a 2:1 ratio. So, if you are adding 200#, which would be 100# per corner, you would up the springs by 1 kg and get 7s instead of the default 6s.

The other way to look at this, which is more appropriate for highway driving, asks that you focus on the frequencies. I will post the entire set of formulae if you'd like, but it roughly comes down to using the square-root of the above ratio, which would put you closer to the original 6 kg than to 7 kg. So, if you trust TEIN and want an even ride at 65 mph, you should probably get the default springs, even with a loaded trunk.

With all that said, I personally would move some weight transfer to the rear, so I would probably get 10/8 springs if I were to run TEINs. But that's a tad aggressive and would be pretty nasty on the street (what with every bump slamming the rear of the car upwards), so I'm back to suggesting 7 kg springs in the rear of your car. The other option would be to leave the rears at 6 and back off on the front to 9. If you aren't going to race, there's little reason to have 550s in the front.

- Jtoby

 

[allshow_2g]

Originally posted by jtmcinder
There are two ways to approach this issue. One has you focus on the weight to spring ratio. So, if the rear corners of a 2G usually carry about 650# each and TEIN thinks that you should have 335s (i.e., 6 kg), then they are suggesting about a 2:1 ratio. So, if you are adding 200#, which would be 100# per corner, you would up the springs by 1 kg and get 7s instead of the default 6s.

The other way to look at this, which is more appropriate for highway driving, asks that you focus on the frequencies. I will post the entire set of formulae if you'd like, but it roughly comes down to using the square-root of the above ratio, which would put you closer to the original 6 kg than to 7 kg. So, if you trust TEIN and want an even ride at 65 mph, you should probably get the default springs, even with a loaded trunk.

With all that said, I personally would move some weight transfer to the rear, so I would probably get 10/8 springs if I were to run TEINs. But that's a tad aggressive and would be pretty nasty on the street (what with every bump slamming the rear of the car upwards), so I'm back to suggesting 7 kg springs in the rear of your car. The other option would be to leave the rears at 6 and back off on the front to 9. If you aren't going to race, there's little reason to have 550s in the front.

- Jtoby

Jtoby, thanks for the very informative post. It brings up a few new questions though.

In the second paragraph you say having 7 kg rear will be bad for crusing at 65mph. I'm not sure exactly what you mean. Are you saying that the faster the car is going the stiffer it gets (worser ride, bumpy ride I guess)? I like to take my car to 100mph quite often, and I'd like a nice ride but have it in control, feeling the stiffness (not sure exactly how to explain that, I think you get me here).

I don't know how 550 feels in the front, um I do like street racing, so if thats good for me, then I may want it or I may not if it feels like your driving on rocks. How would you say it compares to KYB AGX shocks w/Tein S-Tech springs (my current setup)? I guess just looking for a rough estimate, kinda to give me an idea.

But lastly, I don't know like what kind of springs they offer. Or what kind would be ideal (what I was saying to Paul basically). Also wondering if that affects the cost. I guess I'll try and email them later tonight and see what they say, but I never seen anyone offering different springs with Tein coilover setups so I'm not familier with that at all.

I guess your saying either go with softer front same rear or same front stiffer rear to balance it out. Guess I just now need to figure out which would be better. But if I'm planning on adding a turbo setup to the engine in the future, that addes weight, making me think of going with 550's. Also I'm adding power windows, and more insoluation, so the car will be slightly heavier than it already is, .

Thanks for your time so far guys!!

 

[allshow_2g]

Oh and another thing...

For the Tein Flex coilovers, is there anything else I need to buy? I dunno how they work, so I dunno if I need camber kits as well or if that is like included in the coilover kit somehow or what not. (wow long sentence...)

Basically everything I need to buy to make this thing work.

 

[jtmcinder]

One place where the relative frequencies of the front and rear suspensions play a role is in the levelness of the ride of the car at speed. If the frequencies are just right, when you hit a cross-road bump (at the speed the car was designed to cruise at), the front of the car goes up slower than the rear, giving the rear some time to "catch up" (as it were), so the whole car seems to rise and then fall as a unit. If the rears are too soft, then the front goes up and, then, as the front is coming back down, the rear finally goes up, which can make for a stomach-churning pitch. If the rears are too hard, the rears actually catch up and pass the fronts, such that you seem to be launched off each bump and then settle down, butt first, which is also unpleasant.

With that said ...
When I first got new springs, I spent a bunch of time calculating the rates to get a level ride at 65 mph. A year or so later, I threw these values out the window and got stiffer rears, because I wanted less understeer. It's another tradeoff. And it's one where the motto of "performance is king" implies "ignore me," so I apologize for bringing it up ... I was probably just doing it to show off.

- Jtoby