DIY Coilover Folks Please entAr!

[jaredperry]

I took it u on myself to build a set of coilovers for my dime and I have a couple questions.  I constructed my kit with the following items:

 

Rear:

-Subaru Loyale Struts

-Ebay Coils / Locking collars

-2.5" DI HDPE Material for top Hats

 

Front:

Ebay lower bump stops

Ebay universal Camber plates

T3 Top hats

Ebay coils / Locking collars

MR2 Inserts

Shortened Housings

McMaster Carr Locking nuts

 

Overall I feel Mehh about the set up.  The rear is good with the "shot in the dark" spring rate and the average feeling rebound.  I actually would like to believe say that the rear is good to go.  The only real issue I have is the front.  The car literally feels jarred when a marginal bump is hit.  There is a clunk on transitions and it sounds like the damn thing is falling apart.  I have adjusted the spring height and have gotten nothing good from the adjustments.  I have come to the conclusion that the strut insert may be too tall and that there is not enough room for the shock to actually do what is supposed to.

 

The reason I think this is because when the strut assembly is out of the vehicle, the springs hang out low and the shock top is pretty high up, as in there is about 6-8" of the shock rod exposed until there is a load on the assembly.

 

So the questions we have all been waiting for...

 

Why does it clunk?

 

Is there supposed to be strut rod exposure?

 

How long are the coil springs supposed to be?

 

What is the shortest strut insert I should use in this case?

 

Should I just spend the money on a T3 setup so I will stop complaining?

 

 

 

 

 

[flatcat19]

I like when people answer their own questions. 

 

lulz

[datzenmike]

FRONTS...

Shortened housings.... does this mean the strut tubes were shortened, if so how much?

MR2 inserts................. Must fit into the shortened tubes. Any left over space below must be filled with a spacer or washers to support the insert.

Lower bump stops?..... Do you mean bump steer spacers?

 

 

Other questions...

 

The spring length is a function of the spring rate, wire diameter, coil diameter and number of coils. There is no exact answer for this.

 

Yes the strut rod will be exposed. If not exposed how can it compress into the strut?

 

Clunking could be the insert bottoming out or wrong spring rate. Too stiff like 500 pounds/inch.

 

 

 

 

 

 

So these Ebay coils... what spring rate did you ask for??? Do you know what the stock rate is? because you have to know that before you can order stiffer ones. Before attempting this maybe some research should have been done? 

[jaredperry]

The housings were shortened to fit the inserts.

 

Yes, I meant bump steer spacers.

 

When I mean exposed, they pertrute far above the coils when held.  Maybe I could do an MS Paint drawing... ha ha

 

Do you have any suggestions on Ideal spring rates for DD and slammed datto?

[Just Joel]

FYI DD and slammed will never be ideal ;) your compromising a lot when you lower a car this much. Ideally, you want a rate around 175 lbs (what I run) for DD status but because your so low, you'll need a siffer rate to keep the car from bottoming. I'd say you'd need to run something 250 lbs + but that's just a guess seeing as I couldn't possibly know your preference in ride characteristics or your perception of "ideal"

[Stupid_fast]

Why not S13(89-93 240sx) coilovers  

 

Go look how its done on a 280zx.  Same way on a 510.  

Megan, bc racing, stance, PBM, fortune auto ...  I hear PBM are designed to go low.  Need custom threaded sleeve though as the ones they come with are aluminum.

 

8k(448lb)/6k(336lb) springs usually too stiff for a street 510, but if your ride is slammed they may actually be right for it. 6k front 5k rear would probably be better ride quality.  Depends on where and how you drive. 

 

With a coilover setup like this you can adjust ride height without changing shock travel.  When you lower with a ground control style, you take travel out of the shock and the spring is no longer seated on its perch ... when suspension droops there is basically no spring rate... when comes back down you get a clunk as the spring slaps back into its seat.

 

Most datsun guys probably don't do it due to cost.  I want to 4-link my wagon just so I can run s13 coils. 

 

 

 

OR cheap solution shorten your front struts and run good MR2 inserts and stiff springs like most of the 510 guys do.  I have that setup... whatever it works.

 

 

@Just Joel ... IDK I feel higher spring rate with matching shocks makes it more comfortable.  Maybe its the difference of how the roads are over here, but I couldn't imagine taking spring rate out of mine and its not slammed !

[datzenmike]

FYI DD and slammed will never be ideal ;) your compromising a lot when you lower a car this much. Ideally, you want a rate around 175 lbs (what I run) for DD status but because your so low, you'll need a siffer rate to keep the car from bottoming. I'd say you'd need to run something 250 lbs + but that's just a guess seeing as I couldn't possibly know your preference in ride characteristics or your perception of "ideal"

.

So again what spring rates did you get from Ebay? Need to know where you are so you can plan where you want to go. If unknown that's good too.

 

Stock front 510 spring rate is 89 pounds per inch. The rears are almost 4 times that because they are cantilevered. Say about 300/350 lb/in. If running a coil over, the shock is much closer to the axle so something that matches the front could be used.

 

 

 

FYI DD and slammed will never be ideal ;) your compromising a lot when you lower a car this much. Ideally, you want a rate around 175 lbs (what I run) for DD status but because your so low, you'll need a siffer rate to keep the car from bottoming. I'd say you'd need to run something 250 lbs + but that's just a guess seeing as I couldn't possibly know your preference in ride characteristics or your perception of "ideal"

.

 

 

Severely lowered and raced 510s see 300 lb/in on the front and 1,200 lb/in on the rears. This is way too much for simply driving on the street. Every one is different. I think 175/200 would be tops for me. 300 is way too much so maybe around 225/250 would be good as Joel said. The thing to do is start light and work your way up till you get where you are comfortable.

 

Have you given thought to the mad rear wheel camber this lowering is going to cause? Nothing looks quite as retarded and rear wheels tilted in at the tops. Research '510 slotted rear cross member'

 

 

I made my own height adjustable struts (for my 710) and cut the stock spring to raise the rate 50% to 150 lb./in.. It's nice and I thought it ideal, but the last year or so I've thought of going higher. Joel I was afraid of too stiff and not liking it but 175 may be the perfect compromise.

[Just Joel]

I started with #250 then tried #200 before finally arriving at 175 lbs springs. I felt the ride was far to stiff with the higher rates even with the takicos set at the softest setting. After reducing the rate, I now have the shocks set at half way (3 out of 6) and I feel the ride is responsive and far smoother than before. All and all I'm happy with the suspension up front at this point but again, I'm not extremely low. :)

[Uber Deaf One]

Severely lowered and raced 510s see 300 lb/in on the front and 1,200 lb/in on the rears. This is way too much for simply driving on the street. Every one is different. I think 175/200 would be tops for me. 300 is way too much so maybe around 225/250 would be good as Joel said. The thing to do is start light and work your way up till you get where you are comfortable.

 

I run 275 lb up front with my DD KA 510, and 1000-1100 lb springs in the rear.  My dad has a bad back and one of my buddys has a bad back.. neither of them have issues riding in or driving my car.  It's not slammed but it's pretty low.  Keep in mind you also need shocks that can control stiff springs, if your ride is bouncy your shocks aren't stiff enough.  Ride quality is improved a LOT with shocks that can control the springs.  

 

510s are so light you don't need a shitton of springrate to keep ride height under control.  It's all personal preference though, and my 510 is setup for autox/track driving.  It also has a heavier KA up front... L series 510s shouldn't need as much springrate.

 

Just my 2 cents.