63Corvette

I have always thought that the C5 Z06 was almost perfectly set up from the factory. I know about the T1 kit, but think the Z06 stock suspension is fine for daily driving, and also very good for occasional track usage. (NOT racing) SO, my car is a street car, with only a couple of Corvette club track events per year. I have run with scrub slicks from GT Racing tire (for purely economic reasons), as well as street tires..
New perspective: I have instructed with a C7 Z06/Z07 with Michelin PSS tires which ahd enough stick to blow my mind (NOT CupII tires). Now I realize that although I run Michelin PSS tires (on street and on track), my car has VERY large amounts of body roll, and the stock suspension is too soft (for track usage) with the BEST STREET tires available. Comment?

spdislife

That's been pretty much my experience. Stock suspension is a good compromise for the street and occasional track event. However, my interests and goals evolved and I now run the T1 setup. The only time the car sees the street is to drive it to and from an event. Between the ride and fixed seats, it's no longer practical or enjoyable for the street, but it's awesome for the track!

JeremyGSU

On my '04 Z I added DRM shocks ($450) and Johnny O'Connell sways ($600) along with going to 18's in the front. I run Continental GTI slicks as well.

I found the handling much improved with that setup over the stock setup and it's not expensive.

Having said that, a lot of guys run Nitto NT05's for the track. They aren't super expensive and have good grip.

I also think can get the Michelin PSS's in 275 or 285 and 305.

spdislife

I ran those for a couple years and IMHO they provide a good cost vs grip ratio.

Just about used up my 1st set of NT01s and I like them alot!

miracle_whip4130

I would definitely agree. I'm in the same boat as I have a dual purpose C5Z. I took a ride in my instructor's C7 Z06/Z07 at Sebring and was blown away by the grip it had.

YYZ06

+1 on the JOC sways. Really helps to reduce the body roll without hurting the ride on the street. I really like mine.

racebum

depends on the track. i'd MUCH rather drive a loose car than a tight one. if you have some glass smooth track being stiff i could see and or with more traction

but

on the pss the stock c5z suspension is really good. the stiffer the car gets the more likely you are to loose traction over any uneven terrain and the harder the car becomes to save. if you're actually watching lap times i think a lot of guys would be surprised at what they turn in. i also think many like the stiffer car simply because it can "feel fast" even if the stopwatch says otherwise

just depends on your goal. if you change it i'd overlook all the garbage mods people use and find a nice set of adjustable penske or moton coilovers you can buy multiple springs for and revalve if need be.

spdislife

True, but for me, I'd rather not spend a track weekend trying to adjust my coilovers. That's why I chose the T1. Proven and simple.

Supercharged111

Stiffer suspension heats the tires more too if you're tracking that sort of thing. It can be necessary when sticky tires roll the body too far and screw with the alignment or with aero, but soft certainly isn't slow.

racebum

i almost mentioned that. agree. seems to work great on R comps, very well thought out setup and a lot cheaper than moton. probably what i would try and find if i modded mine simply because i don't want to spend countless hours on coilovers getting the car dialed. been there, done that. not fun and very time consuming to do it right and make changes

the T1s only issue is it's lack of adjustability.

then again, if you move past r comps you have so many more issues to deal with...like

dry sump
1200 dollar set of hubs
chassis bracing
$5000 brakes
etc

spdislife

True, no adjustability on the T1. But for most of us doing HPDE, it's a simple and rewarding upgrade. I had looked at some coilover packages awhile back. I'm not sure if it was Pfadt or LG who had a setup with only 3 adjustments. That might be something I would consider.

As far a "black crack" or slicks, most of the C5 guys I run with get by without a dry sump. The hub upgrade I did 18 months ago gives me piece of mind in those high speed corners with no runoff (seen too many failures of the OEMs). Brakes would help but in HPDE if you back up the braking zone, a mild upgrade to the fronts (like the Wilwoods from KNS I did, around 2500) work well.

Chassis bracing? Other than getting the car caged I know, of no other means of doing so.

Bottom line is almost everyone is always looking for a way to get quicker. I have yet to run slicks because of the economics and the fact that I can run an aweful lot of guys down running slicks with my R Comps. I know when I cross that line, there'll never be any turning back

I had some coaching this year from a NASA time trials champ. Very valuable. Had him drive my car and when I saw what he could do with it (which was f**king spectacular!), it inspired my driving!

There's always a way to go faster. Whether it's improving the car, or the driver.

63Corvette

Jeremy..........WHERE can you get 18" 305s??????????????

JeremyGSU

I don't know that you can. I was just guessing. I didn't do any research on that.

Sorry about that.

63Corvette

Michelin shows a 285X18 and even a 295 with an astrisk, which says "France market only". I don't even see a 305, but if they make one and I can find them then I will buy some............Michelin, ya hear that?

LiteraCola

Lots of great info, guys! I've been thinking about a suspension upgrade on my C5Z but I very rarely go any crazier than the occasional autocross event. I dream of coilovers one day (mainly for the looks of a super low C5), but it would probably be more worth my time and $$$ to just go with the JOC stuff.

0aFe POWER

PM me if you want those JOC swaybars

NemesisC5

Surprised nobody mentioned polygraphite bushings. I had the Pfadt (purchased before they went out of business) units on my 02 C5Z and they made the steering notably more precise and responsive. I see the value of the T1 setup mentioned above, proven combination... add the PG bushings and it would handle like a go-kart. At one time GM sold T1 control arms already fitted with a harder durometer bushing.

rjwz28

I didn't know they discontinued the 295/35-18 for US sales... what a crock

spdislife

True. I use poly and for the $ it's a good improvement. I prefer the 2 piece bushing for ease of installation. I may switch to delrin this off season.

ptindall

I think the sway bars are the weakest link by a wide margin. Replace those and end the body roll first and you might be happy with the results without going any further.