suspension problem

lelonsbl

Member
Messages
13
hi i have a problem with my suspension. at the exit of the bend the car bounces. Anyone had such a problem and solved it?
coilovers - yellowspeed dynamic pro sport, spring rate f-12, r-20
in this video you can clearly see what I mean

 

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JustinEET

Active Member
Messages
76
If it's at the exit when you start to apply throttle. I'm guessing the engine is unsettling the car.
What mounts are you using?
 

lelonsbl

Member
Messages
13
stiffened original mounts.

but that's not it. It also jumps when it falls into a bump or grater
 

JustinEET

Active Member
Messages
76
stiffened original mounts.

but that's not it. It also jumps when it falls into a bump or grater

Well if its bouncy could be the dampers. You are surprisingly running way stiffer rates than I've seen on Dynamic Pro's;
did they do those custom rates for you 12kg/mm and 20kg/mm?
 

carl hammond

Advanced Member
Messages
3,458
I think this is a combination of a few things, how hard do you have the suspension set too (how many clicks etc)? and the spring rates, those spring rates are very aggressive.

Area's version of these (which they use on the civic cup cars are recommended to run 8kg front and 16kg rear), you have 20kg rear which is very harsh, this issue maybe (depending on how hard you have the suspension set being a case of the springs being too hard and the dampers set too soft to control them properly)

I would say play around with the dampening a bit (if it's soft then see how it acts when stiffened a little more and vice versa, it will also be different for each track/surface you are on.

More seriously though do you have the harness tied to the harness bar? if so that's dangerous, a harness bar is only to be used as a harness guide to allow the harness to be within the required degree of angle and not to be a support to hold a harness bar, if you have an accident the bar will bend and the harness slacken ending in a bad way for you. In my build thread I show how I used to have a harness bar in my car and where to mount the harness as recommended by Takata etc when not running a cage.
 

lelonsbl

Member
Messages
13
Well if its bouncy could be the dampers. You are surprisingly running way stiffer rates than I've seen on Dynamic Pro's;
did they do those custom rates for you 12kg/mm and 20kg/mm?
no, its standard dynamic pro sport with changed springs
I think this is a combination of a few things, how hard do you have the suspension set too (how many clicks etc)? and the spring rates, those spring rates are very aggressive.

Area's version of these (which they use on the civic cup cars are recommended to run 8kg front and 16kg rear), you have 20kg rear which is very harsh, this issue maybe (depending on how hard you have the suspension set being a case of the springs being too hard and the dampers set too soft to control them properly)

I would say play around with the dampening a bit (if it's soft then see how it acts when stiffened a little more and vice versa, it will also be different for each track/surface you are on.

More seriously though do you have the harness tied to the harness bar? if so that's dangerous, a harness bar is only to be used as a harness guide to allow the harness to be within the required degree of angle and not to be a support to hold a harness bar, if you have an accident the bar will bend and the harness slacken ending in a bad way for you. In my build thread I show how I used to have a harness bar in my car and where to mount the harness as recommended by Takata etc when not running a cage.
clicks changed and still the same
I put on hard springs due to the lack of stabilizer bars
I am thinking of buying premium competition, maybe then it will change? are these shock absorbers different from dynamic pro sport?
yes the harness were mounted like that, but it doesn't matter, now there will be a cage
 

carl hammond

Advanced Member
Messages
3,458
no, its standard dynamic pro sport with changed springs


clicks changed and still the same
I put on hard springs due to the lack of stabilizer bars
I am thinking of buying premium competition, maybe then it will change? are these shock absorbers different from dynamic pro sport?
yes the harness were mounted like that, but it doesn't matter, now there will be a cage
I don't know if the premium competition are different to the dynamic pro sport I am afraid as I personally don't like cheaper brand coilovers like YS, I have the Area Motorsport ones as I kept seeing people saying they are the best with no back to back reviews against other brands, so I did a proper back to back review against Bilstein. The Area YS's are not as you'd buy from YS as Area motorsport have adapted them in many ways for use with this and the EP3 chassis for the Civic Cup cars so they are better but the shell is still the same. I like them but if the Bilsteins had more adjustability and adjustable camber/caster then I would never had got these as the quality is far worse on the YS vs Bilsteins,

Good news on the harness bar as that's honestly really dangerous.
 

JustinEET

Active Member
Messages
76
no, its standard dynamic pro sport with changed springs


clicks changed and still the same
I put on hard springs due to the lack of stabilizer bars
I am thinking of buying premium competition, maybe then it will change? are these shock absorbers different from dynamic pro sport?
yes the harness were mounted like that, but it doesn't matter, now there will be a cage
Ok, so that's what I was thinking. You are running way more aggressive spring rates on dampers that were valved for much softer springs. I'm sure that's putting a lot of stress on the dampers internals. Did you talk to Yellow Speed before increasing the rates so drastically? Those springs are going to be causing much faster rebound.
 

lelonsbl

Member
Messages
13
I haven't spoken to YS. I had no idea that the shock absorber was adapted to a given spring. I thought it could be changed freely

1605018560930.png
 

carl hammond

Advanced Member
Messages
3,458
Ok, so that's what I was thinking. You are running way more aggressive spring rates on dampers that were valved for much softer springs. I'm sure that's putting a lot of stress on the dampers internals. Did you talk to Yellow Speed before increasing the rates so drastically? Those springs are going to be causing much faster rebound.
I believe this is why area rebuild the YS’s they sell and use on cup cars so they can cope I’m with their stiffer springs (pp’s springs are even harsher than areas ones
 

JustinEET

Active Member
Messages
76
I haven't spoken to YS. I had no idea that the shock absorber was adapted to a given spring. I thought it could be changed freely

View attachment 7357
Yes, you can get away with small changes. Especially if you don't track the car. As Carl mentioned Area's version is rebuilt by them and runs stiffer rates. I think standard dynamic pro coilovers are around 8k F and 9k R. You are actually running the exact same rates as my advanced pro plus w/ external reservoirs. 12kg F and 20kg R.

I like yellow speed but the dynamic pro is their standard mass produced coilovers which is why it has no build time. I'm absolutely positive running those rates over a period of time has hurt them.

Maybe you can chat with Yellow speed or Area motorsports and they can help rebuild them for you. I dunno if that's a typical service they offer but it's at least worth a chat

This is taken from Area Motorsports excerpt on their version of the Dynamic Pro's

"Our track versions feature:

Caster Adjustable Top Mounts ( +2.5-3 Degrees of Caster) Hugely beneficial on the EP3/DC5 Type R’s
Locking Washers to prevent movement on track
Eibach Rear Race Springs 16 K/G
Fully Hand re-Built by us ready to fit
All Dampers Dyno Matched as standard from factory and through testing the valving works perfectly with these spring rates"
 
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