09-25-2019, 12:35 PM | #29 | |
Drives: 2015 Z/28 #0058 Join Date: Apr 2018
Location: Pittsburgh, PA
Posts: 814
|
Quote:
So for example: it's 4-6 weeks to just repair the heads only? That with a core exchange (fixed heads ready to go on the shelf) or do you take my heads off the car, machine the heads, and then return the same heads to my car? Just want to confirm what is going on for the 4-6 weeks my car would be sitting there. Inside/outside storage? Engine open without the heads on it? Could you elaborate on the time needed for for each of these options? 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 Not to be nit-picky... but most of us would have to travel good distances to and from katech to drop off and pick up the cars and having the cars just sitting there unnecessarily is also of concern.
__________________
Current:
- '15 Z/28 #0058 | White | A/C | Speakers | Michelin PS4S 305/30/19's - '22 Ridgeline RTL | White | Ebony, '22 CR-V EX-L Hybrid | White | Ebony Sold: - '15 Z/28 #0048 | White | A/C | Speakers | Michelin PS4S 305/30/19's https://www.instagram.com/__jon__athan__/ Last edited by j o n; 09-25-2019 at 12:47 PM. |
|
09-25-2019, 12:54 PM | #30 | |
Drives: 14 Camaro SS 1LE Join Date: Feb 2019
Location: Clinton Twp, MI
Posts: 483
|
Quote:
There is no core exchange, we re-machine your existing cylinder heads. The car will always be stored inside, we would not be overfilling the shop to the point where we had to store cars outside. This is why we would have scheduling slots for a group buy like this. We seal off all of the ports/fittings/hoses that are exposed when the heads are removed. You will not have to worry about debris getting into the engine. ~4-6 Weeks Max Stage 2 Head/Cam (Includes the Head Fix): $8,055.00 ~3-4 Weeks Max Head Fix Only: $4,194.47 ~3-4 Weeks Max Head Fix + CNC Ports: $4,597.50 ~3-4 Weeks Max Head Fix + CNC Ports + Chambers: $4706.4 Again, if everything was scheduled accordingly and we have all of the parts prepared prior to arrival, this time can be decreased. If there are hard deadlines that you need to hit and you have to have your car by, we can discuss that as well. |
|
09-25-2019, 01:11 PM | #31 | |
Drives: Black 2015 Z28 #457 Join Date: Sep 2016
Location: Dallas, TX
Posts: 214
|
Quote:
|
|
09-25-2019, 01:34 PM | #32 |
Drives: N/A Join Date: Apr 2016
Location: Sweden
Posts: 44
|
What would the price for head fix and stage 2 package be without the installation?
|
09-25-2019, 02:02 PM | #33 |
Raging Bull Reborn
Drives: '09 CGM Z063LZ '15 RH Z/28 #0631 Join Date: Mar 2012
Location: Broken Arrow OK
Posts: 765
|
An old member who visits occasionally.I read every thread on this issue that matters. Too many answers on the corvette forum we’re just so much throw away replies. On the Z06 personally I think there are issues...I’ve got one and need to do my heads. On my Z/28 I’ll slog along, having a 7 year 70000 mile warranty, so before I do anything mechanical, I’ll enforce my warranty.
However an article by Hib Halverson over on the corvette action center called “The Ruthless Pursuit of Power, The Mystique of the 7 Liter 7000 rpm LS7” details the changes in the later LS7s in our Z/28s as well as later produced crate engines. These were changes in super polished valves and improved valve guise install and 100%inspection. Check out the article, pages 18 to 22. I’ve posted the several times every time these issues are raised. The reason I paid $1500 for a premium warranty...to avoid any valve issues. Personally I love the LS7, and there are only about 200 dropped valves out of 10807 engines (or so). That’s roughly 9000 zZ06s and 1807 Z/28s. https://www.corvetteactioncenter.com...te-ls7-engine/
__________________
Toy 1 '15 RH Z/28 w/AC & Radio S/N 0631 Toy 2 '09 CGM Z06 3LZ My DD: '17 Ford Mustang GT Her DD: '14 F150 Ecoboost 3.5 |
09-25-2019, 02:23 PM | #34 | ||
Drives: 14 Camaro SS 1LE Join Date: Feb 2019
Location: Clinton Twp, MI
Posts: 483
|
Quote:
Quote:
GM did improve their LS7 head production quality in the later model years, but we have found that they still seem to wear out (even if it is at a decreased rate). There is no 100% issue to point a finger at throughout the whole process, but the majority of the parties involved suspect that there was a supplier quality issue. The issue was in the machining process for the cylinder heads that involved the valve guide bores. You can set clearances to be 100% correct from stem-to-guide, but this does not always mean the valve is 100% concentric to the valve seat. |
||
09-25-2019, 02:31 PM | #35 |
Raging Bull Reborn
Drives: '09 CGM Z063LZ '15 RH Z/28 #0631 Join Date: Mar 2012
Location: Broken Arrow OK
Posts: 765
|
Search on the Katech website is your friend
__________________
Toy 1 '15 RH Z/28 w/AC & Radio S/N 0631 Toy 2 '09 CGM Z06 3LZ My DD: '17 Ford Mustang GT Her DD: '14 F150 Ecoboost 3.5 |
09-26-2019, 08:49 AM | #36 |
Drives: 14 Camaro SS 1LE Join Date: Feb 2019
Location: Clinton Twp, MI
Posts: 483
|
|
09-30-2019, 06:34 PM | #37 | |
Drives: 2015 Z/28 Black Join Date: Nov 2016
Location: Los Angeles
Posts: 340
|
Quote:
__________________
2015 Black Z/28
70 Chevelle SS396 01 M3, 88 Land Cruiser |
|
09-30-2019, 07:42 PM | #38 |
Drives: 2018 ZLE (M6/hyper blue) Join Date: Nov 2015
Location: Lithia, FL
Posts: 762
|
Do you guys have just straight purchase without providing cores? I'd be curious of the price if so, with or without the discount.
From what I understand, the bronze valve guides arent as good as the PM guides in terms of longevity (my Z/28 is a street only car, barely raced, and want to get as many miles as possible before rebuilding a thing). That being said, if the answer to the above question about the sale without a core is "yes", is it possible to get PM guides? |
09-30-2019, 07:57 PM | #39 | |
Drives: 2018 ZLE (M6/hyper blue) Join Date: Nov 2015
Location: Lithia, FL
Posts: 762
|
Quote:
For me the link you sent didn't work, so just providing another, starting at the page you referenced https://www.corvetteactioncenter.com...-engine18.html |
|
10-01-2019, 10:43 AM | #40 | ||
Drives: 14 Camaro SS 1LE Join Date: Feb 2019
Location: Clinton Twp, MI
Posts: 483
|
Quote:
Quote:
As far as the bronze versus powdered metal guides go, in theory the PM would be more durable than the bronze (with the proper valve material), but we do not have any extended test data on this. What we do know is our bronze guides paired with our ti/mo valves holds up to tons of abuse, and it will last for the life of the engine. We did the research years ago with other types of material for both the guide and the valve, this resulted in our bronze + ti/mo combination. In the original post, there is data showing a customer that came in for a 20k mile + 10 HPDE guide check-up. This shows that our solution will last. To answer your questions: -Yes, we can bare cylinder heads and fix the guides with no core -No, we will not use PM guides with our Ti/Mo valves. This combination may work, but we do not have validation data on this and would not be able to stand behind a product with no data. |
||
10-01-2019, 01:09 PM | #41 | |
Drives: 2018 ZLE (M6/hyper blue) Join Date: Nov 2015
Location: Lithia, FL
Posts: 762
|
Quote:
Whats the price without cores? I just want something to bolt on and go basically; might be interested in the additional porting and such too if it gets a tad more power. Feel free to PM it if you don't want to publicly announce that cost |
|
10-01-2019, 02:11 PM | #42 |
Drives: 14 Camaro SS 1LE Join Date: Feb 2019
Location: Clinton Twp, MI
Posts: 483
|
PM'ed. Are you planning on tuning the vehicle after putting the new heads on, or are you leaving it stock?
|
|
|
|
|