021z

Hey Guys, I am about 2 months into owning my 07Z and wanted to get some opinions on which way I should go with making sure my heads are fixed for good. I could buy an extended warranty for about 2k for 3 years but I want to mod this thing a bit and have fun with it. I have a few options that I have found and would like some feedback on the best/cost effective way to make sure this thing runs strong for a few years.

Option 1- LPE is about 2-3k for porting plus new PM guides and stock valves with aftermarket springs, retainers etc.

Option 2- WCCH is 2k with bronze guides stock reused ti intake and new REV LS7 Exhaust Valve and aftermarket springs.

Option 3- PRC LS7x 265cc CNC Heads $3200.

Any other options I am missing?

Thanks, David

ctsv510

Multiple other options are available from American Heritage:

http://forums.corvetteforum.com/c6-z...-specials.html

TRSCobra

Here's who I went with. They offer options/combos that many others do not, at a good price. Excellent customer support, also.

http://forums.corvetteforum.com/c6-z...-specials.html

TRSCobra

021z

That is a great additional option with American Heritage. Thanks for posting! Which option did you guys go with and how are they running?

TRSCobra

I went with option 4 plus a .020 mill. I also got all the gaskets, bolts, pushrods, etc. from them, whichsaved me a ton of time and shipping costs. I've got about 400 miles on the heads/cam swap (untuned right now) and no issues. Best customer service I've ever recieved from any business. I can't say enough good stuff about them.. I'll post up a thread about my whole experience after I get tuned this week.

ctsv510

I went with WCCH Stage 2 milled 0.020"

Can't complain at all, car runs great and I gained 30 rwhp with the heads and a re-tune on a previously tuned car with headers.

JUSTAC6

TRScobra, mind sending me a PM of all of that work plus gaskets?

ProEFI

how about MAST 285, am waiting for mine to arrived in the next 2 days.

MyLS1Hauls

Have you checked to see if your heads are even out of spec? Those listed above are all viable options, but nobody has proven that any head modifications are permanently fixing the issue. I would just keep that in mind. It's not the Ronco Showtime Rotisserie. You can't just "set it and forget it". I would plan on checking the clearances again, around 20k miles. I've even seen aftermarket LS7 castings, with worn guides.

Livernois Motorsports is another option. I just had mine in there for a refresh, and turnaround time was very fast, and price was in line with others. Took them less than 2 weeks, once I made up my mind on what I wanted to do. They also offer multiple options...bronze or PM guides, whatever exhaust valves you want to use, porting/no porting, milled/unmilled. The advantage of being local, was that I could stop by and watch the progress. Their work is top notch. Wish I had taken a pic. They were almost too nice to put back on the car.

Dirty Howie

I have Option 2 and am happy and feel secure pushing it on the track


DH

Unreal

Mast, All Pro, RHS, Brodix, Livernois etc. Plenty of other options.

American Heritage

Our turnaround time on LS7 heads is 5-7 days. We also have 2 core sets of LS7 heads available (requires refundable core deposit). PM, call or email us with any questions. All the other guys in this thread with our heads, Thank You For Your Business.
Oh and as mentioned above by TSRCobra we provide support as part of the sale. What this means is you do it yourself (DIY) guys can call/text/email us with questions and we will gladly walk you though the R&R process (including time saving tips). This is a 24/7 service and is included with the purchase of you heads.

Jasonoff

Maybe I shouldn't ask this here but I'm curious of the wear characteristics between the bronze guide and the pm guide you offer.

'06 Quicksilver Z06

I recall your post below from back in September, where you mention:

What type of new guides did they replace the worn guides with?

What kind of shape were your heads in prior to this latest refresh you mention in this current thread?

How did the new guides hold up, as well as the original ones, and how many total miles did you have on them after the work done on them which you mentioned back in September?

Thanks.

LanceFitzgiben

Keep in mind that if you do go with a full aftermarket head you can sell your stock heads for around a grand, recouping some of the cost.

sriser

Which complete aftermarkets are plug and play? With reworked LS7 castings still, its seems, having guide wear issues, maybe a full aftermarket is a better call with cost offset with the sale of the LS7 heads?

Mark2009

No cylinder head is plug and play. Well, they could be, but I've yet to see any offered with that level of testing/setup prior to shipment (detailed documentation of individual spring installed heights, spring pressure checks, geometry checks, etc).

This explains why some, including aftermarkets, fail.

The quality of a finished cylinder head depends directly on the skill of the machinist who worked on it and the quality of the parts used in it (GM/Linamar has already taught us that). That means that, other than some very high horsepower situations ('6-bolt' heads), there is no end-user difference between a stock rebuilt cylinder head and a brand new aftermarket cylinder head -- either could be 'better' depending on . . . .

. . . . . the skill of the machinist who worked on it and the quality of the parts used in it.

More often than not you are not going to see top quality parts offered in 'package' cylinder head deals, at least not throughout. You are going to see parts that can be obtained at a low price. There are exceptions (Katech comes to mind), but they are not particularly popular because they are more expensive (the top name parts they use, such as PSI springs, don't come cheap).

NavyAirTraffic

I went with American Heritage. Kohle is very knowledgeable and was always available (and never rushed) to answer my questions. Here is my AH experience.

MyLS1Hauls

There were actually 3 exhaust guides replaced 2 years ago, around the 7k mark (I didn't own the car then, which is why I was off on the mileage and number of replaced guides...I recently checked the paperwork). They were replaced with PM guides. None of the intake guides were replaced, since they were in spec. All seats were recut, valves cleaned up, and their dual springs were also installed. A .675" lift cam was installed at the same time.

Fast forward to this spring. The heads now have ~26k total on them. 7 of the intake guides, and 2 of the ORIGINAL exhaust guides were between .0037" and .005". I decided to have all 16 guides replaced, so everything would be the same. I went with PM guides, although they did have bronze as well. Their opinion is that PM guides are more durable. Had the stock intake valves cleaned up and reused. The finish on the stems was as smooth as glass. I also went with brand new OEM exhaust valves. A few of the original ones had galling on the stems, and some pitting on the faces. All 16 seats were also recut to the same depth. This way the valve tips are all at the same height.