SteveDoten

Completed a motor swap on a 2002 Z06, vin was in the 22,000 range with a build date of Feb.2002

mileage was 80k, car was bone stock

2003/4 Z06's having this problem?

toyotabike

Good bye motor.........

hxrly

Definitely something that has me concerned. Just got the car recently, and from what I've read this seems to be the biggest issue even for stock engines.

It would be great if we could track a VIN or time period range. Are there any upgrades that guarantee the spring will not fail, or it is advisable to replace them every certain miles?

baxsom

there are no guarantees on anything but a set of aftermarket springs is a good idea.

BlueTeamZ06

Just do it. Get the compression tool and it will take you maybe three hours. On the scale of difficulty, if an oil change is 1 and an engine swap is 10, the valvespring change is a 3...

BlueTeamZ06

Do you believe stiffer springs are a good idea with stock cam/pushrods? I was steered away from this by some knowledgeable people.

AU N EGL

No.

Most of the problems were with the 01s and a few 02s. But sill not that many.

baxsom

always get springs that are matched for your cam. lots of people are liking the PAC 1218s and COMP 918s for stock replacement out to mild aftermarket cams.

SteveDoten

Correct, the liner is cracked as seen in pics and also cracked the aluminum block

The ZO6

Mine is a Feb 2002 build date as well. Bought it in Aug of last yr and had the classic oil spray on the back of the bumper. My intent was to change the springs out immediately but got around to it last month. Original springs 116K. #7 valve guide was broke in half but I was lucky it never dropped. Good as rain now.

Sorry to see that happen to you. It isn't no fun and heavy on the wallet depending on what you're gonna do.

SteveDoten

this was not my car; valve guide cracked? any pics of that? haven't seen that happen before

Toque

Damm ! Thats crazy !

Toque

NatB

If any concern, just swap the springs out. I used PAC 1218's and all new seals.

Not too hard, just take your time and use a good torque wrench.

I used the "rope " method instead of compressed air- which took a while longer.

Bad Karma

I'm new to the Z06 as well, and from what I have read, just change them, change them now. Any yellow valve spring is in danger of exploding.

I am planning on using the GMPP Valve Springs to go with the stock cam. I'll upgrade later if I decide a cam is in my future.

J0KER

Is this correct? I thought only 02's and up had the issue. I know for sure the 01 springs are different than 02-04's...

Anyone?

fatlt1

there are people with 03's and 04's that have the same problems. my buddy has a 2004 and one day at the light just sitting his car idled down so low and ran like **** and he had to floor it to get it going. pulled the valve cover off and what do you know, broken spring. but yea until then and seeing the op's pic man im a beliver in this. swap them springs right away. that pic above is unbelievable how it destroyed it like that wow.

Nicholas_W

I've got an 01, and I asked on here in a another valve spring thread and was told it was primarily a 02-03 issue, with some 04's having problems as well. NOT the 01's.

93Polo

I do know of an '01 that lost a valve spring:
http://forums.corvetteforum.com/c5-t...lfunction.html

The car did have some track days on it. I would think about a spring replacement if over 80k especially if it has been driven aggressively at all.

NatB

FWIW- I studied many , if not all, the forum posts on valve spring failure related to the Z05/C5 . Finally , I decided this past Spring (haha) to replace my 2002's Springs.

While the issue seemed more prevalent with the 2002 model year, I remember reading about the issues extending into the 2003 model year. Largely resolved by the 2004 model run.

Apparently not an issue with the 2001 Z06 due to the engine having a milder cam profile.

That said, my 2 cents is that the failure is still pretty isolated even to the 2002 model Z06. I replaced mine because I was bored and this forum caused me to become paranoid. Bad news travels fast on these forums, while no one will post how well their valve springs are working

I have also read about new Z06's dropping valves due to spring failure. This is always a risk with a high performance aggressive cam.

Probably not a bad idea to replace the valve springs every 25,000 miles as PM.

C7LOU

I'd like to swap mine out. I've done a little modding on my 03 Z, but all bolt on stuff - headers, lights, exhaust, etc. I have no experience opening up an engine!