Hey guys, i'm thinking i've had my coupe for a year and a half so it's time to let the mod bug unleash, just wondering if anyone out there has lowered their car with just springs and how does it ride? i'm not looking to slam it, maybe just drop the wheel well gap an inch, so would springs suffice? or is it going to make a huge difference by not going for the coilover strut w/spring combo?

 

I'm in the same place you are:

Specifically:

1.
Finding the Max spring drop that the 2003+ Coupe OEM struts and shocks can take before needing new struts/shocks.

2.
Finding the Max spring rate that the 2003+ Coupe OEM struts and shocks can take before needing new struts/shocks. How far from the OEM 314#/342# spring rates will the OEM struts/shocks take.

3.
How much can I drop it without needing CC plates?

here's a start for you:
https://g35driver.com/forums/brakes-...w-updates.html

IMO..So far I'm finding a lot of gooey science for a car this old...there should be a general consensus thread by now.

A1. If you get no help, I'd just get the springs you want (based on the thread) and save for struts/shocks.
If the springs make short work of the OEMs, you will need new ones.
CC plates will be evident if you can't get an alignment..

A2: CO is often overkill for a DD, and a huge $$ up front.

I'm trying to spread the cost of this mod out over time...

Good luck to us both..

 

If you're just looking for an inch drop, zhtechs should do the job perfectly and you can run them on your oem struts fine (they will accelerate the wearing out of your struts, but not nearly as bad as other springs such as ones with a bigger drop). I would even sell you the ones I have, but shipping to you would probably be expensive.

There is a thread around for pics of drops on htechs and stechs, you should look at that and other threads to see what kind of drop you're looking for exactly. Also you can run pretty much any spring setup on your oem struts fine and just replace them with something better such as blue's/koni/s/etc. when they run out. Or do it all at one time if you want the increased handling and not having to bother with switching them out anytime soon.

 

Thanks for the help! That thread definitely helps, i have no desire to slam my g to the ground and join the 'stancenation' crew so i shouldn't be going as far as needing cc plates!

Thanks for the response.

I guess i'll just start out with the springs and go for the higher end mod when i'm better edumecated, if anyone has a 'modbug for idiot noobs' guide out there for me, i'll take it.

 

I am definitely in the same boat. Thank you for asking and answering these questions!!

 

Do the springs and shocks at the same time...Otherwise you will just spend more $$down the road to swap out shocks later...

 

^listen to him. That is exactly what I did when I got my z htechs and tockico blues

 

Leaning toward the H&R sports...as they are progressive and this is the wife's car.
then KYB or Bilsteins.

But I wouldn't rule out a package deal either.

I would be supplying the "free" labor and don't mind revisiting the scene of the crime though.
I want to get my wife addicted so as to make the mod approval path easier for me in the future...;-)

If the car were all mine, I'd slap some whitelines on it.

Thanks.

 

are you looking for looks or performance? They are not always compatible. To lower your car and actually increase handling costs a lot of money.

here is a good guide on some basics, especially focused on shocks:
http://farnorthracing.com/autocross_secrets2.html

here are great articles, mostly talking about suspension geometry:
http://www.motoiq.com/tech/the_ultim..._handling.aspx

So the problem with springs is that you have to make compromises everywhere. So shocks and shock forces are mated to and dependent on the spring rate. When your shock is too stiff for the spring, the ride is terribly uncomfortable and the wheel skips around and loses traction. When the shock is too soft for the spring, the chassis bounces around (like the crappy slammed civics).

The problem with the spring rate is it is greatly influenced by the ride height. The lower the car, the higher the spring rate you need in order not to bottom out. So when you are changing just the spring, you can't increase the spring rate too much, since the ride will get to bouncy, but you want to increase it, since you have less bump travel and otherwise will bottom out. Bottoming out the suspension is BAD, and kills your shocks and over time bends your frame and stresses just about everything and kills any traction you have. Luckily, a stock g35 has a little more bump travel than it needs for daily driving, because it is designed to carry luggage, groceries, and extra people for a sedan. So you may be moderately safe in a minimal drop, with little to no change in the spring rate, but you would want to basically never carry cargo again. If you put some effort into it, you can do the calculations yourself to see what ride height you need for your spring rate. This is a good one: http://www.racingaspirations.com/whe...ncy-calculator where static deflection is the bump travel you need.

a side note on shocks, they are not all created equal. If you care about performance, you should stay with reputable brands. Brands that are reputable on the track, not on the street. like bilstein, koni, kw, and stay away from japanese/taiwanese/korean/chinese stuff

PS we have shocks, not struts.

edit: addendum, if you change your wheels to bigger wheels, you will almost always add unsprung weight. Adding unsprung weight is basically like making your springs softer in terms of wheel rate, which means that you need more bump travel. So if you drop your car without seriously ramping up your spring rate and getting matching shocks, i would highly recommend you either stay with whatever wheels you have, or get ultralights in whatever size you have, or even better downsize to 17" ultra lights.

 

Thanks from all of us for the link.

I want lowering and performance.

I just don't know the G35 platform yet.

I have a 1999 mustang cobra with almost every suspension mod except CO; So I get the trade-offs and concepts and the unsprung weight issues even though I am a DD.
I know the G35 is nearly 50/50 balanced as well!! NICE.
See my posts/signature on SVTP!!

It's the wife's car so I think the H&R sports will be a good compromise...for HER!!...even though I don't like progressives myself.

I can see a G35 as my back up car someday.
My 2002 Audi A4 Q 3.0 w/stick is a dead end for mods and the AWD won't be needed in FL...

Shocks only, aye.
Duly noted.
Thanks for those golden links....totopo....that's the meaty forum support I'm looking for..now someone's talking my language..
I may have found my future track car!!!

 

I agree that you need to do both at the same time, it will save a headache not needed

 

From what I've heard any aftermarket springs will wear out your OEM shocks quickly depending on the height of the drop. If you're going to put springs on, you might as well grab a set of aftermarket shocks to go with it and have it installed at the same time. If you don't, the shocks will wear out and you will need to spend extra labor changing out your shocks when you could have done them at the same time with your springs.