Picked up my 03 Z back in January, have 17,500 miles now, only mods thus far are Xpel film for the front, vararam intake, custom tune, new plugs/wires/springs. As summer closes out and the last few months of driving season come up for us in the NE, I'm debating on what my next mods will be for the winter.

I've decided I'm either going to do LT headers or full suspension - cost-wise they're roughly the same. The install of the suspension will about match the install/tune of the headers. I would do bilstein sport shocks, rear control arm bushings, sway bars/endlinks/bushings from Xplosive. Or I'd get some 1-7/8" LT headers from either stainless works or LG w/ catted mids.

While I only have 17k, the car sat a good while near the ocean in a garage and the bushings are all well worn/weathered. The stock shocks are still in good shape and the ride/handling seems decent (I need to get rid of the Goodyear F1's but that's a different story and probably will be the mod following this one) - I mention the tires because I already overcome the traction capability of these w/ only 366whp easily, although it is fun.

Right now I'm leaning on doing the headers to get them out of the way since they pretty much serve as the benchmark for future mods, and they will enhance my exhaust note & provide a nice bump in power. Also, after installing them, I'll have a fun time destroying the stock rubber next spring.

What would you do and why?

 

depends what you use the car for...track guys love to tweak suspension parts around so they can be quick around corners..to most of them handling comes before power.
If you use your car for certain track events and likes to do spirit driving here and there I would definitely go with LTs. They really wake up the car especially with the Vararaam intake. Tires are a must, goodyears will just make you go sideways and you are going to hate your car and it will hate you back for leaving it with those tires

 

Replace the tires. Now.

Suspension mods will improve ride/handling. The small power bump from headers/tune will improve straight line acceleration.

The increased grip of soft performance tires will improve BOTH ride/handling AND straight line acceleration.

 

hahaha yeah I know but they still have plenty of tread. After 4500 miles w/ the car I pretty much know the limits of the stock hard tires at this point, and believe me they're not as bad as you'd think even being 12 years old. They're not good by any means, but not dangerous. Usually after spinning them up real good a few times and getting some heat in them they hold corners fairly well, but straight line acceleration grip in 1st & 1/2 of 2nd @ WOT is non-existant.

I think I'll get the headers on in late fall save some money over the winter & get some Nitto NT05s and when I take it out of storage smoke the bejeesus off the goodyears (yes I'll video it) en route to the shop to get my Nittos on lol

I don't track the car (don't care about 1/4 mile much anymore and no good road courses worth driving to in NE that I know of - Englishtown is a long haul from Boston) - and most of my driving is nice weather cruising, windy roads, highway romps, basically joyriding and going on weekend road trips. I have had full suspension overhauls on past performance cars though and know how substantial the difference can be so I do plan on it, but I'm a HP guy first and foremost.

 

 

Sounds like you've made your decision. My 03 Z has the original tires(7k miles ) and my first mod will be new michelins and an alignment. After that, I will do headers next spring.

 

Yeah I need the tires, but if I go w/ new tires then headers I know when I first get the headers on ill wanna get on it all the time all over the place, so better to get that outta my system while the stock Goodyears are still in place then throw the nittos on

 

I would rather have my Z sit on stock tires and get fresh ones in the spring. That being said i would get headers first unless your looking for wheels and find a set u like used. Or whatever you find used first - if your shopping in the used market.

Whatever you decide i'm sure it will be lots of new found fun!

 

why would you get bilstein shocks? the sports are valved about like 02 shocks and the DRMs people say are stiffer still. on the street this does not make you faster

stock suspension is about ideal for a 200-300utqg tire. if anything the 04 shocks would increase rear compliance and rear traction

headers aren't a bad idea as if there's anything the Z needs it's more top end.

get 04z shocks and a good alignment and deal hunt on headers. as we go into winter shops slow down and they usually don't mind dealing

 

12 year old tires are debatable for safety anymore. I would be replacing them immediately. Beyond that, tire tech has come a LONG way in 12 years and a set of proper tires will be a huge difference for the car.

 

The stock shocks are actually more expensive #1 and my experience w/ GM performance suspensions - the GTO, g8 both fe2 and fe3, they all are great and perform well for a period of time then just go to hell and ride like crap. I had bilstein 5100 shocks on my 07 silverado and they were awesome put 80,000 miles on the and they basically didn't wear. Reason I will overhaul the suspension is the entire undercarriage is oxidized and dried out from sitting in a garage next to the coast for years not being driven. If I'm going to the trouble of getting all the bushings swapped (including control arm) and installing new sway bars etc I may as well replace the shocks and go with a set that will last for all intents and purposes- indefinitely. And since they're also cheaper all the better.

As for the headers that's a good idea and I did plan on snatching them in dec or jan, not so much for top end (I know they'll help) as for sound, looks, and I just enjoy having a full exhaust on my gm lsx vehicles (silverado, GTO, g8 all had LTs - so far my new 14 sierra does not).

I don't drive in the rain or cold weather and I'm not new to high power vehicles so I still think I can wait in the tires, but like I said they will come shortly after my header install next spring.

I've done a lot of research and seems that for the money the bilstein sports are the best bet- while I agree the 04s may actually be valved better and more specifically engineered for the application, I can't justify paying more for them than bilstein and I don't feel like they will hold up as well.

 

Suspension upgrade will add fun to your driving experience.

 

shocks are a big opinion thing. the sports aren't bad, they are just extremely similar to the 02 shocks

also, if you have 12yr old tires, i'd absolutely place a new set of nt05s if you're on stock wheels above headers. with tires that old you'll already have no traction so more hp is basically meaningless

 

Have you ever taken your car to your local road race course to participate in a track day event???

 

I have not, I would like to - that is something I'd like to do eventually, but I want to spend money on mods before I do that (not that it is super expensive - but you CAN break your car and/or accelerate wear/tear obviously)

I live in MA - so my options are EXTREMELY limited. Basically NHMS in Loudon, which I am not sure how often they have open events, or Lime Kiln in CT.

I have been to New ENgland dragway numerous times in my previous cars/bikes - but that's just 1/4 mile and IMO a good way to break your car.

 

if you want to be fast, the #1 thing you can do is practice. there is almost always more time in improving the tires and brakes than their is in adding HP. in fact it's not uncommon to see high hp cars wind up slower than less powerful cars as guys start building cars that overwhelm available traction

being fast is all about traction and being able to carry momentum through your lines

 

I ask because you really don't need to do any mods to your car other than sticky tires ( toyos or nittos) and grabby brake pads ( Hawk HP Plus) to turn your car into a beast at any track. I guaranty you can not out drive your C5 Z now. They are great cars right out of the box. As nearly every semi pro and pro driver has told me, everyone wants to sell you something. Ron Fellows told me personally out at his school in Spring Mountain NV. Don't bother spending money on the car. Spend it on track time! Seat time, seat time, seat time!!!
He said the C5 Z is the best car you could buy for all around driving. Bar none.
That's why I bought one.

 

Yeah I hear all that, but I'm not really looking to turn the car into a track rat (although I do agree it is an excellent platform for that) - I started this thread w/ the full intention that I am modding the car and spending $1500 -/+ on this next go around regardless. I am more looking to have the car all sorted out (and in my mind - a muscle/sports car isn't properly sorted out w/o headers) - the suspension also needs attention because the bushings and all the AL parts are badly oxidized - so that's why I was looking at tackling that, the added handling benefit is only anecdotal.

I use the car mainly as a weekend warrior, road trips, windy roads, occasional car show, and may take it to the dragway or road course even once a year.

So while I'm fully aware the Z is more than capable for the track out of the box, that isn't necessarily my intentions for the car. If it was, then yes - my first mod would have been tires, followed by sway bars. Since I'd rather smoke the bejeesus off the stock rubber before I get rid of them, I'll put the headers on first in very early spring, then throw tires on early summer.

Lastly - I don't know where all you guys hail from, but there simply isn't easy track access in the northern new england area, plus we have weather to contend with - not saying its not possible, but its much more of a process.

 

really don't even need sway bars with street tires. adding more roll resistance just makes the car "skippy" on uneven terrain. the factory really did a good job for leafspring suspension stock. it's really tailored around the traction of a street tire

get R comps or slicks and it's a different story entirely.

the old T1 package really didn't add all that much roll stiffness to the z06 and that was a track only design

remember, the entire purpose of the aftermarket is to separate you from your money, this is why their marketing would have you believe the whole car needs to be fixed

 

Of course you don't need them. But for me, stiffer sway bars greatly added to the driving experience - and I've never run a tire less than 200 treadwear. Hotchkis' sways offered me: 1) more responsive steering, 2) more confidence at high speeds, 3) better transitional stability (i.e. making a quick right turn directly after a left, or vice versa), and 4) the ability to adjust oversteer/understeer balance. I highly recommend aftermarket adjustable sway bars as a performance mod for the C5Z, assuming tires have already been taken care of.