I know myself, I notice a big difference when I switch out the 19's for the stock 16's.

 

Do you have bad roads where you live?

 

Ya, I hear that. I suppose the Vette's & 5th Gens can get away with bigger rims due to IRS.

 

But being that I am running a taller profile tire, wouldn't they negate the effects of a larger rims? The stock 275/40R17 tire is 25.66" tall with a sidewall height of 4.3". Usually to stay within OEM height, people opt for a 275/35R18 which would be 25.58" tall and has a sidewall height of 3.79". I am running a 275/40R18 which is 26.66" tall and its sidewall height is 4.3". In fact my 295/40R18 tire in the rear is 27.29" tall and has a sidewall height of 4.65" - wouldn't that make it "softer" than 17" rims with OEM size tires?

It's 50/50 I'd say. Certain areas of the city are well paved but other sections are pretty bad.

 

Mass x acceleration = force. You've added unsprung weight with the larger wheel and tire.

 

So what exactly is occurring with the suspension. We know you don't like it. If you want to fix a certain symptom though, you kind of need to know what it is first before you can counter it with a change.

 

You know, maybe I'm not as sensitive as other people but I got 600lb front springs and 200lb rear springs, both linear, my front DA's are 5 sweeps from full soft and the rear SA's are a full turn from soft, my car drives and feels great so my back must be more tolerant???

It feels so much nicer than the factory shocks and springs but then again I haven't had the deCarbons and factory springs since 2006.

 

^^^ This

 

Do you know if your impacting full suspension travel too fast? Or is this not occurring and you think the suspension is just too stiff.

Yeah you definitely are adding a bit more unsprung weight to the wheel.

 

Finally took the TA out from its slumber tonight for a joy ride then I was quickly reminded why I don't enjoy riding it!

I'm going to play with a few things:

- Recheck all bolts front to back and make sure everything is tight
- Taking out subframe connectors (jus' experimenting)
- Lower tire pressure a lil' bit more
- Make sure rear is set on full soft (It's either on full soft or one click away)
- Set the fronts to a softer rebound setting (Should I go full soft on rear?)

Anything else I should check out? If I'm still not happy, I may switch to SLP Eibach's springs.

 

Well I think I made some progress. I took off the subframe connectors and adjusted the front Koni's to 2 sweeps from full soft; orginally they were 4 sweeps). The car seemed to have softened up but I want to take it on the expressway and see how it feels before I jump ahead of myself.

Unfortunately, there is still a hollow tin-like knock in the front when hitting a bump. The rear seems a lil' clunky too. It's not the same sound but more of a muffled clunking. I think I hear the rear springs unloading and loading too. You know that sound when you lift from the rear and the spring makes that noise?

Again, I have an Adj. Poly/Roto LCA and I don't want to switch these out because without them, my rear wheels are offset in the wheel well. Should I switch the Roto joint to a Poly?

 

Oh heck no. Poly will make it worse.

 

all I have is a stock suspension with Hyperflex bushings all around and I LOVE driving my car. It's like driving a slot car. Sometimes I just go for a ride in the country on winding roads for an hour or two. I love my Z.