SSMOKE

Mileage - 10,000 when WCCH Stage II heads were installed. TORQUER 110 installed at the same time. 17,200 miles today. (6/23/16) I drive my Z06 about 2,000 miles a year.

Material - My OEM heads with 10,000 miles were replaced with a different set of OEM heads, also with 10,000 miles and only after the OEM heads that I bought as replacements were sent to WCCH for their Stage II package. I never had my originals measured and only bought new heads because I did not want to drop a valve.

Parts - Tumble polished OEM intakes, one piece SS exhaust, bronze guides and BTR dual springs. BSM Performance installed the heads and cam and tuned the car. (561/511)

Car used for - A few spirited drives, three or four weekends a month.

Cam - TORQUER 110

Follow up disassembly and data. - Nothing has been disassembled yet, but cold starts, after the car has been sitting Mo through Fr, blow smoke out the exhaust like a forest fire, all eight of my spark plugs are oily and I am a quart low 1,300 miles into my last oil change. NOT HAPPY. DISGUSTED in fact.

Oil change intervals - . Seven oil changes in seven years. Minimum miles between changes was 600 miles after I got the heads and cam installed, the most was 5,000 after the second heads/cam oil change.

Type of oil - Mobil 1 until the heads/cam install and Redline 5W30 after the heads and cam. Again NOT HAPPY about this.

AzDave47

Clarify the heads that are blowing smoke on startup are the WCCH worked heads or the new OEM second set unmodified that you bought?

SSMOKE

AzDave47 the heads that are on my car now, that blow smoke, are OEM heads that I bought off CF from a guy in FL. I had the seller in FL send those heads, straight from FL to CA and WCCH. WCCH did Stage II and sent them to me in Hawaii. Once I received those reworked heads from WCCH they were installed on my car and I sold the stock heads were on my car to someone without ever measuring them.

I don't know what exactly is wrong and/or why my car is blowing smoke, but these are the facts and, as mentioned, while I really do like my car and enjoy driving it immensely, the fact that it is blowing smoke is troublesome and irritating. Add to that, that I no longer have a competent mechanic (The original mechanic and LS specialist moved to Vegas.) I am really at a crossroads.

Dirty Howie

HOpe it turns out to be something simple. Are you saying it BLUE smoke??


DH

outhouse

After sitting for 5 days, smoking is usually guides or guide seals, more so then rings.

AzDave47

hopefully just the seals as replacing those is not a major cost.

daveinsguy

Mobil one 5-30

ToppThat

2008 Z06 Mast 305 heads. 13000 miles 2nd build used mast 285 first time

Yella-Zee-427

2006 Z06
Who: Horsepower Addicts DE
(Stock heads had .006 wiggle on the valves)
HPA Stage 1 Heads
HPA Blower Cam
25,XXX miles
Miles since repair: approx 200 miles and still grinning
***Added ARH headers and Catless Xpipe. Corsa sport out back.

toofast07

Horsepower addicts
Stage 1 heads replaced my old heads with 2009 heads redone
Hpa comp 501 cam
Hpa muffler mod.
2k miles all is good but muffler mod rattle after 100 mile one month,rattles bad guessing pipe weld came loose wanted to have Hpa fix but they ignored my email and text guess they don't stand behind there work

ToppThat

My mod job never rattled and I did it myself. But I guess I over do everything.

Yella-Zee-427

Did you try calling them?

RamAir972003

Is this after every cold start up. Second its normal for the car to eat some oil plus do u have a catch can also.....

fierogt28

Since I'm new to this info about the Z06s cylinder head valve problem, I understand GMs supplier that made the heads screwed up on the machining side of things, what year C6 Z06 was this issue corrected?

outhouse

AHP!!!!!


2006 Z06 43k


4 exh out of spec all other exh right at limit.


All int within spec

AzDave47

It was never corrected, and Linimar, the GM vendor managed to screw up about 4000 e-difs for the C7 by underfilling them prior to delivery. Strange incentive, reward screwups.

fierogt28

Thanks for the info...btw, what's e-difs?

Was this for the 2014 stingray, or 2015 Z06s?

AzDave47

Electronic differential for the 2015 Z06's. Checking tranny/dif fluid levels are not part of the pre-delivery inspection, even with Museum delivery. The fellow from CA that took delivery at the Museum and had the dif fail in TX on his way home was not a happy camper!

fierogt28

My goodness, so that means that every Z06 in the C6 line-up (2006-13) will need to be fixed / cylinder head replaced to have a longer engine life set-up...hmmm.

Very concerning for that C7...GM better step-up to the plate and resolve this issues. Who ever is responsible for quality control better learn from these mistakes. This is a huge blow for Corvette buyers and owners.
GM should of had a recall for the cylinder heads from the start.

AzDave47

GM only admits there is an LS7 head problem for some 7/08 to 2/11 heads and that they reverted to 100% inspection of heads after that. The Inspector(s) should be fired as brand new replacement heads have come from GM as late as 2013 with the valve concentricity with the seats outside their own repair spec when the brand new heads were measured. For GM it is a $ issue, if it is out of warranty even if the engine only has 10K miles on it, it doesn't come out of their hide. They don't have to count all those on this forum that are proactive and get the heads fixed on our wallets so we aren't exposed to a $17K out of warranty replacement.

My 09 with 46K miles had all exhaust valve guides and 6 of 8 intake guides out of .0037 spec when they were serviced by WCCH. When would they have failed - I don't know, but I didn't want to play Russian Roulette with my LS7 every time I drove it either.