Hey all so I am currently trying to decide between the Tein street flex and the D2 RS Coils. I have around 1k to spend give or take so the price isn't really a deciding factor at all. I just want the better product, both build wise and performance wise.
My car is a '96 ek civic 2 door with a full b20 swap. currently it is just on cut springs and the ride is F'ing terrible obviously. It is my daily so i would like to have as nice of a ride as possible while being able to go LOW, i know there has to be give and takes between the two but id like the best of both if possible.
So I have read good things about both coils. I have a buddy that says to go with the D2's because his buddy has them and "they are the best". But i have also read reviews on the D2's where people were complaining of how the did not allow the rear to drop as low as the front.. This i a big turnoff to me as that is one of my side-goals is to be able to have the car siting level front to rear. I've also read that the Teins do not hold up to harsh weather and winters as well due to the fact that they are made using steel instead of aluminum, how true this i i have no clue as i have no experience with either coil.

So with all that I want to ask yall's opinions and experiences with both products. which wold you recommend? Thanks!

LINKS: TEIN.com: STREET FLEX - PRODUCTS
http://www.d2racing.com/coilovers/rs-series/

 

Aluminum bottom coilovers do arguably worse in bad weather than steel ones. Because the shock inserts are usually steel...the bottoms are aluminum. Thats a disaster.

Fully aluminum coilovers that are made by reputable companies are usually above the $2500 mark.

Those D2 RS's have aluminum hats (so do the teins, IIRC). But...the bodies are steel. If the lower collars are aluminum and the shock bodies are steel...that's going to corrode SO badly if the anodizing flakes off.

Here are my Tein SA's after some Chicago winters. They are corrosion proofed very well. Mine now have ~36k or more miles on them. They are powder coated...which is much more corrosion resistant than anodizing. And the threads are zinc plated. Zinc provides modest corrosion resistance....but still probably better than anodizing.

I put them on and sprayed the bodies with clear coat.



I would use antisieze on the lock collars on ANY coilover used in harsh conditions....except the german ones that are stainless steel with plastic collars. I also pressure wash the chassis as often as possible to get the salt off in the winter. Car washes have this option. I also have a pressure washer.

The D2's are almost surely steel as well. Teins get my vote, hands down. Better quality. R&D in the USA. Made in Japan.

I'm sure D2 has come a long way since I experienced them like 10 years back (they sucked so badly that my friend sold his car and moved across the country to forget about how badly they sucked).

Then again...Tein has come a long way as well. The original Type Flex I had on my S13 weren't bad....but not that great either. Their new street stuff is VERY impressive and has a european feel to the damping curve.

 

If you have $1000 to spend I highly recommend you save another $100 and go with Fortune Auto.

 

I have never heard of fortune? why do you reccomend those over the Tein?

 

They are assembled in the USA.

Custom spring rates.

Shocks are valved to the spring rates.

Digressive shocks.

Every set comes with an actual shock dyno.

5 year warranty.

They actually know what they are talking about, and they aren't pushing off the shelf, generically valved crap from Taiwan that is made with ZERO R&D or real world testing.

http://www.fortune-auto.com/shockdynobasics.htm

 

I've heard good things about fortune. Never used a set, though. The 5 year warranty is a nice touch, as well as digressive damping (for real?).

Tein does do their own R&D as well....not to take anything away from Fortune Auto.

Its nice that Fortune will set the damping to your choice of rates too. Definitely worth looking at.

 

Hmm Youve caught my interest... am going to have to look into them, andthey are actually made in richmond which is like an hour from my house which is kind of cool.. How is their ride quality? smooth enough for a daily?

 

I like the fact that they also rebuild shocks in house. I would consider these.

 

Well ive been reading up on the Fortune autos and so far they seem decent (besides the fact that there are hardly ANY good reviews around the intereweb). But one thing ive seen that sort of turns me off is the fact that the fortune auto 500's are only single adjustable, whereas the Teins are duel adjustable... How much better is the duel adjustablility?...

 

Teins are not dual adjustable for damping. They adjust bump and rebound together...emphasis on rebound. Just like the fortune auto.

 

Any coilover under $2500 will be 'single' adjustable and adjust rebound and compression together.

 

Gotcha. But from what i was reading (I could be wrong by all means) the Teins allow you to adjust ride hight independently from rebound, where the Fortune Auto's do not... Am i wrong on that?
ALSO, has anyone here used the Fortune Auto's? it's so hard to find someone that has...

 

That's called full body adjustment.

Damping adjustments (rebound and bump) are shock adjustments (stiffness of the shock).

Independent Height adjustment or full body adjustment is the ability to adjust height without affecting shock stroke length. Basically, you thread the entire shock into the bottom mount instead of threading the spring down. They should both do that.

 

For slamming the car...if its not full body adjustable, you're probably just about to have a bad time.

 

Linear springs don't change spring rate with preload.

Just sayin'

 

Not sure what you mean in relation to the topic. They don't change rates...but loading springs up changes the ride and handling quite a bit.

The spring can sometimes top out the damper with most of the car's weight on it.

And it would take more force to compress a preloaded spring than a non-loaded one. If a 500lb/in spring is compressed 1", it will take 1000lbs (total) to compress it an another inch. So...of course preload changes suspension stiffness.

But...what's that have to do with slamming cars?

Being able to adjust height independently from shock stroke is the biggest advantage of full body coilovers.

 

The way you worded that, I can see how you're confused.

Yes, if a spring is compressed 1", it will take a total pressure of 1000 lbs to move it 2 inches. But, if it's compressed one inch, it already has the first 500lbs on it, so all you need is another 500lbs.

If you apply 30 lbs of pressure to an uncompressed linear spring, and 30 lbs to a compressed one, they will move the same distance.


Preload is a marking gimmick on our cars, but you are correct that not reducing the shock stroke is ideal.

 

Lets play with some easy numbers.

Take a 500lb/in spring. Compress it 1" via preload.

Say the car puts 500lbs of force into that shock mounting point at that corner.

When you put the car down...the spring will now compress 0 inches with the wheels on the ground.

The spring is already compressed 1", which is normal...but it will also expand at a much faster rate, with a higher force as the car rebounds from cornering or bumps.

-The car will need ANOTHER 500lb of force to compress it 1" further.
-the shock will run out of stroke before the spring stops expanding at full force. This will also affect piston speed on rebound quite a bit more than having an unloaded spring. There is a minimum of 500lb of upward force on the assembly at any point in its stroke.

Ofcourse that adds roll and ride stiffness.

When the spring has 0 preload on it...it is true that the CAR'S WEIGHT will compress it 1". But...as the car rebounds past ride height, available force is between 500lb and 0 lb, depending on how far the spring is expanded. Minimum is not 500lb of upward force now.

Being able to preload a spring gives you flexibility on shock stroke and force required to compress the spring. Being able to adjust height independently of preload is a useful tool. Not just marketing.

Think about making a transition from left to right. A preloaded spring on the right side doesn't have to start from a lower point to start resisting movement. Its already coiled down...even at full extension.

There are positives and negatives to this type of tuning.

I assure you I'm not confused.