Katech LS7 Head Fix Group Buy

[Katech_Zach]

I will try to answers everyone's responses in one shot:

1) Yes, the discount applies to LS7/LSX Heads.

2) We have worked on a few Z28's and they have all had valve wear issues, I will pull the mileages first thing tomorrow when I am at work

3) The issue started to appear about 5-6 years after the Z06 was first released (2006 MY), it is now roughly 5-6 years after the first Z28 release. As I stated earlier in the post, people are finally getting to the point where they want to put mileage on these vehicles. Typically, around the 15k-20k mileage mark is when we see this issue come up on street vehicles. Track vehicles tend to accelerate this.

4) The valve wiggle test is helpful, but you need the heads off to truly measure what is going on with your valves and valve guides. Your valves could not wiggle at all, but they could still be out of spec and on their way out. The wiggle test can help verify that your guide is out of round (on top of being oversized).

For reference, my family's C6 Z06 had valve guides out of round by nearly .002 at the 22k mile mark.

[Katech_Zach]

I added the 10% off prices for reference in the original post.

I also included that we can upgrade your valvetrain if you wish to do so, we can prepare your heads for a cam swap so you are ready for the future.

[j o n]

Originally Posted by Katech_Zach

I added the 10% off prices for reference in the original post.

I also included that we can upgrade your valvetrain if you wish to do so, we can prepare your heads for a cam swap so you are ready for the future.

Yes, please provide details regarding the full price (and with discount) for the heads and labor included. Also details around the time needed for the swap / install.

Thanks
-Jon

[SS Performance]

I'm very interested.

[Katech_Zach]

There have been a few Z28 owners that have sent their heads in for the head fix and others that have done the stage packages. I do not have the mileage on the cars that sent their heads in, but I do have them for our Stage 2 package.

Z28 #1: Stage 2, 2015 MY, 13,286 Miles
Z28 #2: Stage 2, 2015 MY, 14,401 Miles

As far as vehicle packages are concerned, the two most common packages are the following (All prices after discount):

Stage 2 Head/Cam (Includes the Head Fix): $8,055.00
Head Fix Only: $4,194.47
Head Fix + CNC Ports: $4,597.50
Head Fix + CNC Ports + Chambers: $4706.4

All head fix vehicle jobs include all the proper gaskets, trend pushrods, and arp head bolts.

The Stage 2 package includes:
-Head Fix
-Camshaft of your choice
-Katech C5-R timing chain
-PSI springs
-Katech Titanium retainers
-Bronze valve guides
-Katech Ti/Mo intake valves
-CNC ported cylinder heads
-Your choice of a Fast 102 Intake or MSD Intake
-Wideband O2 bung
-Head gaskets
-ARP head bolts
-160 degree thermostat
-Serialized plaque
-Installation
-Licensing and calibration with HP Tuners
-Baseline dyno
-Chassis dyno tuning
-Chassis dyno sheet comparing baseline to finished product
-3 year/36,000mi warranty

You can add other items/services to our stage package and the price will be adjusted accordingly. I will have to verify with my boss, but the discount should apply to the entire job.

The same prices apply if you wish to use new OEM exhaust valves or Katech Ti/Mo Exhaust valves. We will advise you if any of your existing exhaust valves need to be replaced.

Also an FYI, you have the option to take your OEM titanium intake valves back. Those have some value to them as well.

Timing is very flexible, I can start getting a rough schedule together if people are interested enough to sign up on the list. A simple "put me on the list" reply to the post will let me know to throw you on the list

[Mark_Z28]

Originally Posted by Katech_Zach

I will try to answers everyone's responses in one shot:

1) Yes, the discount applies to LS7/LSX Heads.

2) We have worked on a few Z28's and they have all had valve wear issues, I will pull the mileages first thing tomorrow when I am at work

3) The issue started to appear about 5-6 years after the Z06 was first released (2006 MY), it is now roughly 5-6 years after the first Z28 release. As I stated earlier in the post, people are finally getting to the point where they want to put mileage on these vehicles. Typically, around the 15k-20k mileage mark is when we see this issue come up on street vehicles. Track vehicles tend to accelerate this.

4) The valve wiggle test is helpful, but you need the heads off to truly measure what is going on with your valves and valve guides. Your valves could not wiggle at all, but they could still be out of spec and on their way out. The wiggle test can help verify that your guide is out of round (on top of being oversized).

For reference, my family's C6 Z06 had valve guides out of round by nearly .002 at the 22k mile mark.

Mileage of cars is NOT relevant data unless its accompanied by the wear data on like cars. Tell us what your spec is for valve guide wear(is it 0.002? or is it less or more?) and load up data of what was measured on the few z28s you've seen. Telling me mileages of the cars you worked on doesn't do me any good. Honestly with engineering behind the Katech name your initial response is woefully inadequate and would take you out of contention from my business, because it looks like you're trying to capitalize on the C6 Z06 issues and make some additional business.

[Mark_Z28]

Originally Posted by Katech_Zach

There have been a few Z28 owners that have sent their heads in for the head fix and others that have done the stage packages. I do not have the mileage on the cars that sent their heads in, but I do have them for our Stage 2 package.

Z28 #1: Stage 2, 2015 MY, 13,286 Miles
Z28 #2: Stage 2, 2015 MY, 14,401 Miles

As far as vehicle packages are concerned, the two most common packages are the following (All prices after discount):

Stage 2 Head/Cam (Includes the Head Fix): $8,055.00
Head Fix Only: $4,194.47
Head Fix + CNC Ports: $4,597.50
Head Fix + CNC Ports + Chambers: $4706.4

All head fix vehicle jobs include all the proper gaskets, trend pushrods, and arp head bolts.

The Stage 2 package includes:
-Head Fix
-Camshaft of your choice
-Katech C5-R timing chain
-PSI springs
-Katech Titanium retainers
-Bronze valve guides
-Katech Ti/Mo intake valves
-CNC ported cylinder heads
-Your choice of a Fast 102 Intake or MSD Intake
-Wideband O2 bung
-Head gaskets
-ARP head bolts
-160 degree thermostat
-Serialized plaque
-Installation
-Licensing and calibration with HP Tuners
-Baseline dyno
-Chassis dyno tuning
-Chassis dyno sheet comparing baseline to finished product
-3 year/36,000mi warranty

You can add other items/services to our stage package and the price will be adjusted accordingly. I will have to verify with my boss, but the discount should apply to the entire job.

The same prices apply if you wish to use new OEM exhaust valves or Katech Ti/Mo Exhaust valves. We will advise you if any of your existing exhaust valves need to be replaced.

Also an FYI, you have the option to take your OEM titanium intake valves back. Those have some value to them as well.

Timing is very flexible, I can start getting a rough schedule together if people are interested enough to sign up on the list. A simple "put me on the list" reply to the post will let me know to throw you on the list

So to finalize, you do not have any data showing excess wear on Z28 heads.

[Katech_Zach]

Originally Posted by Mark_Z28

So to finalize, you do not have any data showing excess wear on Z28 heads.

Actually, to finalize we are 2 for 2 (for bad stem-to-guide clearances) on both vehicles that came through our car shop for a head/cam upgrade. We have multiple cylinder head jobs that also show the same signs that were ran through our cylinder head department rather than the car shop. We have detailed valve guide logs from all of the LS7 heads that have ran through our shop, and we have concluded that every GM LS7 head has guide issues. Rarely do we come across a head that is within spec.

Shown below is the pre-fix measurements. These are way out of spec, especially near the bottom of the guide. This is caused by the valve seat machining not being concentric with the valve guide bore machining. Neither of these heads would pass the "wiggle test" due to this "triangular" and "hour-glassing" wear.

We suggest driving the car as you would, but if you begin to hear symptoms of a loud valvetrain or excessive valve noise, this is a sign that your stem-to-guide clearances are out of spec.

We would not run anything over .002 as long as the top, middle, and bottom measurements are consistent. GM considers near .003 to be "within spec" at the max allowance. Both of these heads blow both of these specs out of the water.

[j o n]

Originally Posted by Katech_Zach

As far as vehicle packages are concerned, the two most common packages are the following (All prices after discount):

Stage 2 Head/Cam (Includes the Head Fix): $8,055.00
Head Fix Only: $4,194.47
Head Fix + CNC Ports: $4,597.50
Head Fix + CNC Ports + Chambers: $4706.4

Again, what is the time needed to perform the work...How long will our cars need to be at Katech?

[Mark_Z28]

Originally Posted by Katech_Zach

Actually, to finalize we are 2 for 2 (for bad stem-to-guide clearances) on both vehicles that came through our car shop for a head/cam upgrade. We have multiple cylinder head jobs that also show the same signs that were ran through our cylinder head department rather than the car shop. We have detailed valve guide logs from all of the LS7 heads that have ran through our shop, and we have concluded that every GM LS7 head has guide issues. Rarely do we come across a head that is within spec.

Shown below is the pre-fix measurements. These are way out of spec, especially near the bottom of the guide. This is caused by the valve seat machining not being concentric with the valve guide bore machining. Neither of these heads would pass the "wiggle test" due to this "triangular" and "hour-glassing" wear.

We suggest driving the car as you would, but if you begin to hear symptoms of a loud valvetrain or excessive valve noise, this is a sign that your stem-to-guide clearances are out of spec.

We would not run anything over .002 as long as the top, middle, and bottom measurements are consistent. GM considers near .003 to be "within spec" at the max allowance. Both of these heads blow both of these specs out of the water.

Thank you for the data, truly!

[Katech_Zach]

Originally Posted by j o n

Again, what is the time needed to perform the work...How long will our cars need to be at Katech?

I misinterpreted this the first time you asked, my apologies.

Our typical car shop time from start to finish is 4 to 6 weeks. This can be sped up if scheduling is done properly, but typically jobs are interwoven into a shop that is already at capacity.

If you need the car sooner, this most likely can be arranged as long as we have all of the parts pulled and ready to go, dyno time scheduled, and a tech ready to go.

[Dixon Racing]

I've been eyeing the stage 2 package for a while now, can the kit be ordered without the installation? Would the discount still apply?

[Katech_Zach]

Originally Posted by Mark_Z28

Mileage of cars is NOT relevant data unless its accompanied by the wear data on like cars. Tell us what your spec is for valve guide wear(is it 0.002? or is it less or more?) and load up data of what was measured on the few z28s you've seen. Telling me mileages of the cars you worked on doesn't do me any good. Honestly with engineering behind the Katech name your initial response is woefully inadequate and would take you out of contention from my business, because it looks like you're trying to capitalize on the C6 Z06 issues and make some additional business.

Yes, you are correct. Mileage of the vehicle is technically irrelevant unless there is wear associated with this mileage. I used mileage as a reference because this seems to be the general average from all of the LS7-equipped vehicles that we have had. Some cars are out of spec within a few thousand miles because they are heavily abused, other cars last a life time because they spend their lives under 3000 RPM on the highway.

We consider anything that is over the .002 mark to be out of spec, GM considers around .003 to be the upper bound. Anything that has an "hourglass" shape to the measurement (.0025 top, .002 middle, .003 bottom for example) needs to be addressed because this will cause the valve to wobble. This is where the wiggle test comes into play, the average user can identify if they are horribly out of spec.

We use the solution that has been proven throughout our motorsports history to permanently solve these issues.

[Katech_Zach]

Originally Posted by Dixon Racing

I've been eyeing the stage 2 package for a while now, can the kit be ordered without the installation? Would the discount still apply?

I believe we would be willing to do so, the head fix portion would have to be done through us.

An example of this would be:

1) Ship us your cylinder heads
2) We will fix, and reassemble the heads with the stage 2 components
3) Ship you the finished cylinder heads + the rest of the package