oldbutspry

So I wound up buying my son's 2007 350z. It's lowered with BR Racing coilovers. I like the look but I need to raise it some to improve ride quality and ensure I don't scrape on speed bumps. The roads where I live can be pretty rough. I watched a YouTube video on adjusting the coilovers and am waiting now on the package with the wrenches to arrive.

So here's my question - how much do I need to raise it to get an appreciable difference in ride quality? Would an inch make a big difference? Should I raise it even more?

dkmura

iTrader: (64)

Welcome- this question depends on the spring rate and length of the springs in your kit. Most coilovers have a maximum height to respect, so communicate with the manufacturer. Also, anytime you raise and lower the ride height, you alter key factors in your suspension like negative camber and toe. Always have the car realigned before damaging your tires or the car itself.

oldbutspry

Yes, I am already planning on getting it realigned after the change. I'm just trying to avoid pulling the wheels off to readjust everything more than necessary.

Here's a pic of how low it is now:

travlee

iTrader: (8)

Doesnt look super low to me. What size wheels are on it

MicVelo

To.be perfectly honest, raising the car isn't going to appreciably improve the ride quality because coilovers are, well, almost never comfortable. But you can try to raise it a bit; but I would concentrate on taking out the spring pre-load. That may help a bit.

But if you really want to “improve the ride”, dump the 20s (guess) and get yourself a nice “conservative” set of 18s with sidewalls > rubber bands.

jhc

I agree with the comments above. Those look like mb 25 sidewalls.
I think you owe it to yourself to go to a Caffeine and Octane meet and ask someone with a more traditional setup (18" with 35% sidewalls ) for a 5 minute ride. You might be surprised how much the tires factor in.

oldbutspry

Thanks for the info! The wheels are 20". I didn't realize they made that much difference in ride. I'm not going to bother changing the wheels - I'll just live with the ride. Still, I think I will raise it a bit so I don't have to worry as much about scraping on tall speed bumps.

I've only driven the car about 25 miles so far so I haven't scraped the underside yet but I know my son had some problems scraping sometimes.There are two large speed bumps on the way out of my work that I am particularly worried about. I think I'll drive over there today and crawl over them slowly to see how close it is.

oldbutspry

Well, you guys were right! The car isn't as low as I thought. It made it over the speed bumps at work. The wife and I didn't think there was any way it would. I guess the oversized wheels are so close to the top of the wheel well that it makes the car look lower than it really is.

So I was originally thinking that if I raised the ride height that the amount of suspension travel would increase as well. I'm gathering from what everyone is telling me that that isn't the case?

I see there's an adjustment for damping - is that the same thing as pre-load? I changed the damping to the softest setting on the front and the ride is much less jarring.Now I need to find where to adjust the rear to match. I'm guessing I need to remove the trunk interior? I removed some of the fasteners but it feels like the felt substance is glued on in places. Any suggestions on how I might find the rear dampening adjuster?

ETA: I looked around the convertible top well and there's no access to the coilovers there. Anyone have a link to a tutorial on removing the trunk interior pieces?

jhc

Easier than you might think, just unpin fasteners and bag them, pull the panels off gently. Depending on where you need access, open the Tonneau, park it at vertical and remove the vinyl covering. Everything is there, accessible between the two.

By the way, your sense of humor in screen-names did not escape me (re age), you are in good company as not all of us are wet behind the ears, so to speak. I have a Roadster, lmk if you need help. Take care my friend!

EDIT-
Strictly speaking, "preload" speaks to how tightly the springs are compressed. "Damping" refers to how softly (slowly) or firmly (quickly) the shocks absorb differences in terrain. Quite sure others may have a better description! GL!

rustyschopshop

Ask your son if he had rear adjuster extenders installed. If not you will have to unmount the rear coilovers to adjust. If you need to do this since there are no adjusters, would order a set so you can adjust more easily later.

oldbutspry

Ok, I got the trunk panels loose and looked in the convertible top well. Seems like there's no access. It'll probably be next weekend before I get around to unbolting the coilover and adjusting it that way. Any idea what the bolts should be torqued to when I reinstall?

ETA: Judging form the mod videos I am watching, I must not be the typical 350z owner demographic.

oldbutspry

I'll ask him but I bet he didn't have extenders put in. I didn't see them from the trunk or the top well.

jhc

Actually IIRC, when I did my Eibach springs and Bilstein B8s I do believe all access, wrench-turning was done from underneath the vehicle on the rear. Gl!

bboypuertoroc

iTrader: (4)

Smaller wheels and more tire will do wonders for ride quality. The largest I would ever do on a Z are 19s, and that's solely for looks. Not much else you can do other than remove the coilovers and put something closer to stock in there. Most aftermarket suspension setups are performance oriented so comfort is usually ignored.

Congrats on your new (to you) Z. Cool **** that you kept it in the family.

oldbutspry

Ok, I will pull them and adjust this weekend. Might try changing the ride height and preload as well.

I'll just adjust it and then live with it. I don't expect it to ride like a Buick. I had a 370Z with 19" Rays and the euro-tuned shocks. If I could get this car close to that level of comfort then I would be happy.

oldbutspry

Oh, but I do have another question. The car has the Bose stereo but the head unit has been replaced with a Kenwood DDX393. It sounds fine but the problem is that there's a lot of hiss when the volume is turned down. I assume the gain has been turned up on the amplifier - how do I turn that back down?

oldbutspry

So I got my coilover wrenches today. I set all 4 corners to the softest dampening setting and I reduced the preload on the rear by 2 turns. I also raised the rear coilovers by 3 turns because I saw that the rear was lower than the front when the car is not on a slope.

Now the car is world's better on the road. Much less jarring. Still a tight suspension but not unpleasantly so. Before, it would give the wife a headache from the constant bouncing up and down. Now it rides much more like a normal car.

The car actually still sits a tad low in the rear but I think I'll leave it alone because it is close enough. Maybe someday I will mess with it more if I feel bored.

I'm wondering if I should bother getting it realigned? I know I said I would but the changes I made were pretty minor. I think what made the difference in ride was mostly the dampening. I didn't make any adjustments to the front besides dampening. Thoughts?

dkmura

iTrader: (64)

Anytime you raise the ride height, you've changed camber and toe-in. Get a four wheel alignment before your tires wear unevenly.

oldbutspry

So I decided if I am getting it aligned then I should go ahead and get everything set just right. I set the front pre-load to match the rear and raised the rear a little more. Now it's perfect! Rides better than yesterday and looks better as well now that it isn't squatting in the rear. Plan to get it aligned in a day or two. Thanks for the help!

oldbutspry

Took the car to get it aligned today and they said they couldn't align it because it needs a new upper control arm. So I think I'll just replace them both. Need to look online and figure out which ones to buy.