I have an G35X and I did double check that I have the correct springs. These are not the RWD springs. And the shocks are original and in fine shape. The car has 100,000 km's on it, all highway, and I know the shocks are good.

I just had Hotchkis sways installed a week ago and ride is a little bit stiffer now for sure, in a great way. But now that the springs are in I notice a bit more bounce. I wasn't expecting that. I think I read at least one thread where the initial impression was less roll, better handling, great improvement. Right off the bat. I can't find any posts where anyone mentions more bounce after install. I'm not noticing much improvement over what i already realized with the new sway bars. But I am noticing a bit of bounce.

But to me that kind of makes sense. Spring rate differences between OEM and the PK's aside, I would expect that new springs would have more spring to them and there would be an impression of a bit more bounce. Is that true? Do I just need to give these some time and let them break in and settle?

 

Must improve my searching skills. Looks like this could be an alignment thing more than anything. I was planning on getting one in a couple of weeks. Hoping that will improve things.

 

Alignment definitely needed before coming to any judgements, but what you could be feeling is the progressive nature of the springs. They are initially very soft but get progressively stiffer--the result is bounce on undulating roads or imperfect surfaces. I don't like it but short of going to coilovers, it is a necessary evil to keep the ride comfort close to stock.

 

Anytime a vehicle is dropped you should get alignment done. I think this will resolve most of the "bounce" you are experiencing.

 

I hope you guys are right about the bounce being attributed to the progressive spring (and that it will stiffen up over time) and needing an alignment. I hope it isn't my shocks, but I'll get them checked out by the alignment tech when I take it in.

I do feel like the car is not handling well around corners either. It's not just a weird bounce I'm picking up. There's also something off when cornering. I hope that is all about needing an alignment. After the sways were installed, everything was excellent, but after the shocks, it's pretty bad.

I'm also not that pleased with the drop. It seems pretty high to me still. Unfortunately I forgot to measure the before. But the after has rears at 27" from top of fender to ground and fronts are 27.5". Hopefully I'm due for some settling effect.

 

the bounce is typical..

 

You better be incorrect. The only bounce issues I read about in my research re: lowering an X on this site was when people were installing springs not designed for the X. I have never read any posts regarding there being a bounce when proper springs for the G model/version were installed. In fact just a few threads down UofT raves about the handling performance after installing the springs and no mention of bounce.

If I did read anything about a bounce being typical I would not have done this mod. Why would anyone do a mod that introduces bounce? Why wouldn't there be a ton of threads/posts about this issue? All lI can find is posts about how good it is.

As I said, I hope you are incorrect. Or that I can get of this without too much expense. I'd be willing to slap in 4 new KYB GR-2s if that's what's needed but I need to know that will fix the issue.

Anyway, I'll see how things are after the alignment.

 

I intalled the PK on my car with about 20K on the clock..bottom line the car was more bouncy. I didn''t expect it either, but it wasnt horrible. I think it's just the tradeoff when you move to a higher spring rate and you're using shocks that are not designed for that spring length. As far as an alignment, I think that will help you get back into specs regarding camber, etc, but I don't think it will remedy the extra bounce (at least it didn't for me). In the end, I ended up grabbing a set of coils and never looked back. I should have just done that in the first place since IMO, lower springs are just a stop gap measure to coilovers anyway..

 

I talked to my guy at tirerack about this and he said it could be related to the control arm bushings going out of whack from the spring install work and the sway bars the week before and that putting on some miles will settle them back to normal. I'll have the alignment tech check that out.too. My bud at tirerack also said it could be the shocks.

 

I wish there were more posts stating this in the archives. I would have probably got CO's instead. Now I could be getting new OEM spec KYB shocks and in the end spending about the same at CO's. However, I hear that CO's are stiffer (for track, not ideal for street, however I doubt its really that bad) and not very good in the winter climates which I live in about 6 months out of the year. Because of these premises I stayed away from CO's for my Acura TSX and went with H&R springs and Koni yellows. If the yellows were available for the X I would gladly go the robust performance spring/shock route over CO's even at the same price. It works well on the TSX. Damn, I'm feeling pretty disappointed with the lowering spring approach and this car.

 

CO's come in all different spring rates and flavors. So you def can find a set that suits your needs for the street and some light track days. Personally I went with HKS Hypermax III's. They have full ride height adjustability and 30 way dampening. They have been flawless on the street (feels like a very high end oem suspension) and carves in the canyons.. could not be happier.

 

Subscribing. I am considering a Pro-kit, but if it's going to be a bouncy ride...I'll stick with stock.

 

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I have 100K on my car. I suspect the bounce comes from the worn (but not blown) shocks. And the PK's are not known to be a bouncy spring. I have new KYB's that will be installed next Tuesday. Hoping that fixes the problem.

 

Correct. General rule of thumb is:

Soft dampers (what worn dampers typically default to) - bouncy ride
Stiff dampers - rough ride

 

Worn shocks, which obviously happens and is well documented to happen starting at around 60K miles, will cause a bounce too. I just hope these KYB's, which are supposed to be 10% stiffer than OEMs, are going to be a big improvement over my worn OEM shocks. Not so much because they are 10% stiffer, but because they are brand new.