Spring Rates : John

[James]

Hey John and everyone else, id be interested to here recommended spring rates for my second gen civic for a good sporty ride. I am looking at getting some 36way adjustable coil overs for my car and wondered what springs I should order.

These coil overs will also suit citys, so Ill let you all know how they go.

[wkthyk]

A lot of choices. If you get a japanese brand coilover it usually comes with progressive springs. The cpring rate usually varied from 5 to 14K...I think 6 to 9K springs will enough for civic or city. You can try Tein as they do quite a reasonable price among those Jap brands, and you can put EDFC with it so you can adjust the shocks in your car. If you only want to get a set of spring, you may think about RSR or Quantum. Bilstein is also good, not expensive compare to other Jap brand.

[James]

You didn't quite get it there wkthyk, I know which coil overs I am getting, I just have to pick which spring rates are gonna be best for my car. At the moment I have 6kg in the front and 9kg in the back. The front is a good rate and I think I will stick with that, however the back is wayyy to stiff, I just wanted to hear peoples suggestions.

I doubt that either bilstein or tein or any of those brands have coil overs that will work in my car, they have the same strut mountings as city's, quite different from most modern ones.

EDIT: sorry just re-read my original post, it was pretty vague so I can understand your misunderstanding wkthyk

[wkthyk]

I think using 5 or 6K at rear will be better, more balanced. Most weight and tractions are concentrated at the front, a bit stiffer at front comparing to rear would be better at those slow sharp corners.
But if you are going to drag your car, then F6R9 will be good. That gives you more grip a launch, and good balance when your car speed up and centre of load is transferred to about the middle of car.

You may find a set of springs with prograssive rate, or two springs at one shock with spring separater, such as the HKS Hypermax II setting. Although two springs on one shock will gives you more acurate spring rates than prograssive spring, but that cost you a bit more too and hard to source the ring separating the springs. I used be using a set of HKS prograssive springs on my R33 with Hyper Drag damper. The spring rate is F:11/14 R:9/14. Of cause they are too hard for Civic, and my R33 is RWD. But Prograssive spring can give you a high spring rate under high load with acceptable rate for grip and comfortability at normal drive.
I think I heard Mugen got the springs for old civics, as I heard someone using that before for the 1600cc race in Macau, but I am not quite sure.

[James]

Hmnn some interesting ideas there wythyk. The 9kg rear is even to hard for drag races, any bumps in the road at high speed make the car feel like it is going to lose control. I think I will keep 6kg in the front and go for some 5kg in the rear and see how that suits. I actually have some of those spring seperater things on my car at the moment because I am running coil over springs with keeper springs on standard struts to keep them captive.

I am talking about an '83 civic aswell, eif mugen made stuff for it its not very likely its around now

[Colza]

From what i have been reading in what is left of civic1200.com, 6kg front and 4kg rear with a rear swaybar, or 6kg front and 4.5kg rear with no swaybar.

That is a race setup for a 1200 which will probably be good for your 200kg heavier car on the street.

For my street EB i will be looking for 4.5kg front and 3.5kg rear.

Remember that with the coilovers you can increase your effective spring rate by precompressing the spring. By raising the spring seat by an inch you can add approximately 1 kg/mm (so from 6kg up to 7kg etc)

[James]

Serious? I wondered what preloading it did, I was gonna ask you. You could work it out couldn't you from how much force you are exerting on the spring to compress it that far and stuff.

[John_S.]

Well, I wish I could come up with a simple and to the point answer about this, but I don't have one. I was lucky to get a set of the B+G springs from a USA supplier, but it was their last set. Supposidly they are still available in Sweden where they were made, but I don't know this for sure. I haven't mounted them as yet, but they are made of smaller in diameter material, so I can't even guess as to the ride quality. Jarcaf has them on his 4-DR and he likes them, but with ride quality and handleling what we each like on an individual basis is what it is.
What I will say is this, stiffer springs most of the time do not lead to overall better handleling, at least not by themselves as an improvement. Plus if they are too stiff it can make a car way too unpredictable. The better way to go is to leave a certain amount of compliance in the suspension, then control that compliance with proper sized anti-swaybars, and superior damping action.
Lowering these cars properly is a "'pregnant dog" to  do properly, and always expensive.  All of this above is why I am working on a redesign of the factory strutcap assembly to allow the full action of the strut, and still drop the car. This is also why I haven't mounted all the nice parts on the car. I don't want to ruin the Konis, and just using a shorter spring is simply too risky. Although heavier swaybars would reduce the danger some, I'd much rather wait till I can work out a proper way to drop the body in relation to the strut itself.
Sure would like to finish it up though 'cause those parts will make it handle like you won't believe.
One final thing...I have driven a 2ndGen equipped with larger front and rear bars and no other modifications and it IS worth the money for the proper bars. In fact they are probably the first mod to make after tires and brakes...for the street at least.

[James]

Sweet thanks for your input.

The suspension I have my eye on is a set of 36 way adjustable coil over monotube struts from D2 suspension.

http://www.d2racingsports.com.au/images/d21.jpg

The picture is huge so it will take a while

As you can see from the picture the entire shock body is threaded so this lends itself to be mounted on variety of cars.

This base shock is the same one they use on every type of macpherson strut car that they do kits for, that is why they have such a range of adjustability.

I am going to make some custom bottom mounts that bolt into the pinch fitting on our 2g's and have internal threads so I can raise and lower the car without changing the spring and shock dynamics, this seems like a great way to go about it to me.

The only hassle is the inside of our pinch fittings is like 45 mm and these are 50mm shocks so the shock will always have to sit just above the knuckle, I just hope the shock itself is short enough to get the car decently low with the shocks sitting just above the knuckle.

At the moment I am probably going to go for 5kg/mm springs in the front, as I have 6 at the moment and its pretty good but when I get a beefier front bar then it might be too stiff, I can preload the 5 upto a 6 if i want anyway.

As for the rear I will probably go for a 3.5kg/mm as this is what they recommend for a sporty street spring for a honda city new shape which is about the same size as my car.

I would like to see how the rear bar is mounted because mine doesnt have one on there and it doesnt appear to have the mounting except for the holes in the top of the leading arm to bolt it too.

I was hoping to get away with standard strut tops for now and then change to a pillow-ball style mount when I can to get the possiblity of going a bit lower. I will also fabricate some camber plates so I can control that when I go real low.

Have you got any ideas as to what modifications I can do to reduce the bump steer? It is something chronic at the moment and quite a bit of force is required to hold it stright through funnily contoured road. I guess it will involve re-mounting the steering rack or something

[John_S.]

I don't see a front strut steering bearing in that schematic/ Do they just leave it out? ???

[John_S.]

Oh and regard to bump steer. I just recently read an excellant description of the dynamics of it all on another website in the last week. I think it was on one of the sites I follow about guys building up their old English Ford Anglias,(105 Speed.com), or maybe one of the other numerous sites linked through it concerning Escorts, Cortinas, and/or Capris.
I didn't print it because I was out of paper, so I'll have to find it again. I know it was on one of the forums.
In any case, its all pretty interesting stuff  the mods they are making, and it all follows similar paths and they face similar problems as we face with our modifications on our cars.
I find it hellps me to know their are actually lots of guys out there who though starting with their own choice of "block of Marble", are sculpting some trick "Pocket Pockets", and as you stated earlier they are easily on par with most of the new stuff you can buy today.
But hey, as long as you have they money, almost ANYone can buy a NEW car. ::)

[James]

Yeah I know what you mean. The environment over here is starting to get a bit chilly towards people who modify their cars, due to the 10% of teenage idiots the farked it up for the rest of us, its really annoying

Anyway, with that steering bearing, you see part 2 in that photo, the strut top. That has an integral pillow ball joint as far as I can ascertain. Incase you call them something different thats a ball with a hole in it sitting in a socket, like a track rod end joint with both sides open and a hole through it .

I would like to use their strut tops but they cost several hundred on top of the struts themselves so initially I will try and use the civic strut tops with the top spring cup they from those coilovers, and then when I get up enough money to buy 2 loose pillow balls I will machine up some housings for them with a camber adjusting plate so I can fine tune my settings  ;D

[Colza]

The D2 suspension comes with 'pillow ball' tops on the MacPherson fronts, but not on the rears or the 'A-arm' struts.

[John_S.]

Those pillow balls you speak of, are they lifetime lubed, or do they normally have zerk fittings? I recieved an Email back from the Gent who owns Milton Racing in the UK. The gave me some specifics on the strut cap pieces they manufacture, and also mentioned the same type of setup. He says they tend to last ten years or so, and there is little or no increase in stiffness associated with their conversions, so that path looks good from here...other than price anyway. Just have to save up, and bite the bullet. ;D

[John_S.]

Oh, hey Bigelboe, I forgot to mention that the 1stGen  Prelude front struts are 50mm OD as well as threaded, and therefore the uprights are 50mm ID. They are a direct bolt on  to the Civic except you do have to use the Prelude lower control arms as the balljoint stud is heavier duty. I wonder if you could just permanently bolt down the upright tightning bolt and have the inside of the upright threaded to match those custom struts you are talking about? If that works, it shouldn't monkey with the factory designed in bumpsteer.