So I know what it IS. But I'm not sure how much is really needed or how my plans will affect it. And I'm still building so if I HAVE to change something I can.

So my old setup was:
Tokico illumina/GC
700.250.500 ERS front
700.250.400 ERS rear
GC tophats f/r

New setup:
Koni race (8041-race)/GC
700.250.500 ERS front
600.250.600 ERS rear
GC tophats f/r

Now I have read some peoples thoughts that this combo in the front will not give enough droop? Why is that exactly? I mean max droop is just with the shock fully extended right? Or can the shock droop farther and start to pull back? There will obviously be some preload on the front springs to get ride height dialed in but does that really matter much either? The car will have it's weight on it and take away any preload anyway right?

I'm just wondering how "not enough droop" affects the front suspension and if this is really something I should be concerned about. I also don't like the idea of the spring coming loose at full droop anyway so a little preload seems good right? My old setup the springs were very loose in the rear and a little loose in the front at my ride height. It seems like to have no loose springs at full droop you have to have long soft springs, long progressive springs, helper or zero rate springs added in, or a high ride height.

What are your thoughts on this? Has anyone actually tried this setup?

 

i have basically the same setup as you except for 50lb heavier front and rear(also 7in all four corners). i am not running arbs and probably a lower ride height but i have no problems with the front. at the expo banquet i did see a pic of me lifting my inside rear going into t2 which was a moderate braking zone into a right hand sweeper.

here is a pic for reference under braking in said corner.

 

I know what it is in the power industry!

Im interested in reading a proper reply from someone wiser than I.

 

I'm not really concerned with lifting the rear tire. I've read so much about people doing crazy stuff and still lifting the inside rear. I'm more concerned with what's going on up front and if I should expect any problems.

Thanks for the reply eggizzy. It does seem like you are probably lower than me. Do you have a good amount of preload in the front?

 

yes i do. and unless you bomb a curb and go full droop i dont see why you would have any problems with that setup. it is very forgiving setup. only thing ive noticed is that you get alot of pitch/roll with higher speed corners which i guess should be expected. let me find you a different reference pic of the front inside while cornering.

 

turn in.


sorry im at work so i dont have my laptop or the photomotion disc. so it has the water mark on it.

 

Thanks again. You think that pitch/roll is due to the spring rates? Or related to something else?

 

spring rates yes. i think if i had bars then maybe your droop discussion would come into play more. i think my car rotates very well and very predictable. there are a few people/mods on this board who have seen the car on track or have rode in it. hopefully they will chime in since it is my opinion and obviously everyones is different. but noone has said otherwise..i could give you some in car to look at but it doesnt really give anything that you are looking for.

 

Oh you don't have any sway bars? I forgot to mention that in my original post. I'm running stock crx si bar up front (15-16mm?) and 22mm ST rear bar.

 

yeah i failed to read your sig. there will be some differences then to my references then for your application by how much i dont know. i still wouldnt think much.

 

Up for some more opinions.

 

I don't think you are supposed to run the race version of the koni shocks with the ground control top hats because the shocks are already shortened. But what do I know, I never ran this setup. I mean, why should I even be allowed to comment on it?

Every time somebody asks this droop question, I always say that the first priority is to make sure you have enough compression travel, and then give yourself as much droop as possible, until the springs barely come loose when the car is jacked up.

 

with the GCs, the car would have to be DUMPED to get the springs barely loose. with this setup i may have to put maybe like 1/2-1" preload on the springs to get them at the height i want. but thats 250-500lbs of preload. is that a lot? ive never really dealt with preload before. i assume the car will compress them that much under its weight. so instead of losing that compression stroke with the loose spring setup i retain it and gain more real world compression stroke when the car is on its wheels. but i may be over thinking this. i should be getting my GC koni coil sleeves tomorrow and i have my ride height measurements of where the spring perch should be in relation to the mounting point on the LCA so ill have to see how this setup really is IRL lol. ill take some pics.

as for the rears. i expect them to be fine with the top hats since there is so much more droop available. the springs before were very loose under full droop and the rears arent shortened as much as the fronts (15mm vs 25mm)

 

This may not be a huge help with your current question but I have some advice if you are willing to listen. Whatever ride height you are thinking of running, raise the car another 1/2-1" from there. You probably won't do it, as I didn't do it either. But every really fast Honda I have ever seen road raced/tracked runs higher than the kind of fast guys do. Not picking on Egezzy above but that is a perfect example of a typical ill handling Honda setup. Unless he is running like 1200# front springs I bet he is all over the bump stops or slamming his UCAs into the shock towers. I ran Honda Challenge 02-03 and have done track days since as money allows. I drive the **** out of the car and have always been considered pretty quick. I was slow as ****. I ran one track day with the car 5" from the pinch weld to the ground and was blown away at how well the car turns in and handles. The front wheel well gap is funny and looks almost like a street car. But the suspension actually works now. Just my .02 FWIW. I run 900# front and 1200# rear BTW. I was higher than egezzy and still too low.

 

Droop is not set by changing the spring perch - it is set by moving the mounting position of the shock shaft relative to the chassis, i.e. top hat style.

What u should do is mount the shock without the spring, and compress your suspension all the way until something hits. (Set the bumpstop location to prevent this.) Unscrew the nut that holds the shock shaft to the top hat and push down on the shock shaft until something bottoms. This is the amount of excess compression travel that you don't need. U can use washers or spacers to lower the point where the shock shaft mounts onto the top cap.

 

not sure if this was directed at me, but I know this. But the perch location will affect the ride height and preload which was kind of a secondary question in my last post.

I had to read this a couple times to get it. But basically you are saying to find excess compression then space the top hat back up to gain back some more droop? Right? That sounds like a good plan. My only worry would be running out of threads for the lock nut. I'm going to look into this though and report back.

 

I agree with this guy. Seems like from your description of the preload you will have on the spring just to obtain your desired ride height that your shocks are too short and might need spacing downward at the top hat as beanbag recommends. No need for 3 inches of compression travel if the upper control arm bottoms out after 2.

 

On an EG/DC chassis, a 500lb/in spring up front yields a 230lb/in wheel rate. Assuming a 740lb front corner weight, this yields a static compression of 3" measured at the wheel, 2" measured at the shock. (.68 motion ratio + or -) If you have to pre-load the spring 1" as measured at the shock you will have ~1.5" of droop travel before topping out the shock. With how softly sprung that car is, it's almost assured that you WILL be droop limiting the inside front in roll. This is bad. I've found that 2" of sprung droop travel on a production based sedan is as low as you want to go when racing on smooth tracks with stiff spring rates. If your tracks are bumpy, more droop is not a bad thing. I run 3.5" of sprung droop travel with ~100lbs of pre-load.

The second problem with running Koni race with the GC top hats (besides it being a waste of money) is that the bump stops are too high relative to the top of the damper. The bump stops on the EG/DC chassis are crucial components of the suspension setup. Especially if you choose not to/can't run upwards of 1000lb/in front spring rates. There simply is not enough suspension stroke at a reasonable race ride height to obtain a good static camber number and cg height for the suspension to work without bump stops. You will have to use long bump stops, or use packers to build the bump stop stack height so that your bump stops will be effective enough to prevent the UCA from hammering out your shock tower.

So to recap, by combining the gc top hats with the koni race, you'll have wasted money on the gc top hats, have to run packers/long bump stops to get the stop back where it needs to be (and thus negating the change afforded by the gc top hats) while simultaneously limiting your bump travel and droop limiting the front suspension. Yeah, learn from the money I wasted. Don't do it!

YMMV, my .02, tip your waitress, thanks for flying with us...

 

1. I have a CRX. Generally lighter. Just thought it was worth mentioning. Not saying your info is completely irrelevant or anything, just pointing it out.

2. Money is not really an issue in my case. I bought all 4 tophats from GC like 5 years ago. I'd list them in the "spare parts" category now lol I'm not just now buying them for this setup or anything.

That said. Thanks for the info. One question I have and the lasting question throughout the thread, why exactly is having little droop bad? What happens? How does the car behave that is the problem? I'm looking for a something a little more than a "just because" kind of answer.

I am a little confused about your bumpstop argument though. What do you mean the bumpstop is too high? The bumpstop will be in the same position relative to the shock regardless of top hat used. It sits directly under the stop washer on the shock, which doesn't move. It would make the bumpstop higher relative to the upper mounting location (where the top hat mounts to the body). Also wouldn't running a longer stop reduce the compression travel? I don't think I understand how the stop can affect droop at all

I will try to get the shocks mounted up tonight and see how much travel I have.

Also, what is the "sprung droop travel" you are talking about? Is that measured at the wheel or shock?

Thanks again for the reply and I look forward to answers to these questions. Also if you don't mind, what is your suspension setup?

 

Too little droop makes the tire less capable of following the road surface irregularities. IE, the tire can't "drop" into that pothole. Think of the extreme, where you have zero droop. How well do you think the tire will follow the road surface if it's very bumpy? On the front of a front driver, this would be VERY bad as the tire would just skip all over the place, roll stiffness would be significantly higher then a similar car with droop, etc. Simply put, droop limiting is generally quite poor for handling/grip, especially when done on the driven axle.

There are some formula cars that utilize droop limiting on the front axle, but generally there are overriding concerns such as aero platform stability.

As for the bump stops, visualize the shock, spring, upper perch, and the location of the bushings in the upper perch. Switching to an extended top hat moves the bushings in the upper perch up relative to everything else, (as viewed on the car) and subsequently moves the bump stop "up".

Good point on this being a CRX. Of course, I assumed a 2400lb weight (with driver) with ~61% on the front axle, so the difference won't be very large. Just happened that the numbers worked out pretty simple like that, so I didn't bother going with a lighter vehicle weight to illustrate a point. That said, my experience with Koni yellows on EF's is that they are shorter then stock already with regards to droop travel. The standard length units on my brothers 91 require pre loading a 500lb spring to get the desired ride height, so a shorter unit is bound to have more problems. Of course, I'm not sure if Koni puts a shorter droop limiter in the shock when they build the Race units or if they keep the same length droop limiter as the standard unit. The droop limiters used in the front shocks by Koni are pretty long, so if you find that the shock is too short you could send them back to Koni to have a shorter droop limiter put in the shock. Doesn't address the concerns I have over the bump stop location, but having the nice flat surface for the 2.5" race springs isn't a bad thing...

 

Yeah. That's another reason I wanted to stick with the GC tops too. They are better suited for the 2.5" springs than a stock top hat. I wonder if anyone makes an aftermarket top hat like the GC, just not extended. I'll have to look into that.

Another thing that would be nice is if someone made an aftermarket lower shock fork that allowed independent height adjustment so you wouldn't have to worry about the ride heights affect on preload or droop. But that's way off topic for now lol

 

Skunk2 makes an Al top hat that would do what you're asking. I run them on my car now.

 

Thanks. I'll definitely look into that.

Do you see anything wrong with still using the GC ones in the rear? With my previous setup the springs were loose a full 2" (2" gap between spring and upper mount) and the rears on the koni race are only 15mm shorter. I think it'll be fine, but just asking your opinion.

 

Got a link? I couldn't find them on the site. I need more droop travel in the back on my car to stop the torsen diff unloading coming off the corners, and I was going to go back to OEM top hats, but why not some reasonably priced bling at the same time. I figure I'll get about 3/4" more shock droop (about 1" at the wheel) by taking out the GC top hats that are back there now.

 

Hrm, can't find 'em. Andy Hollis sent me the link, I figured they were easy to find and I was just being lazy. Maybe ping Andy?