[Z06] Most miles on AHP heads?
03-23-2017, 08:51 AM
#21
40-50k seems to be pretty good on the pm guides and honestly what I'd expect. Hopefully Kohle can pop in and confirm all that stuff. Wish I would have went with moldstar sometimes but for what I do the PM should last a long time.
03-23-2017, 11:20 AM
#22
Safety Car
A lot of people showed their true colors last week kicking a dog while it was down.
many cried how harder guides wont even help trying to jump on the bang wagon.
Then some guy post about how his heads with bronze guides only lasted 7000 miles in a 630 hp ish motor, from a crap company who obviously not only used softer guides, but put in some sand paper valves ta boot.
The highest miles reported here so far are from Khole on the m90 guides at 60,000 with no real wear present. Kohle owns the reliability record.
many cried how harder guides wont even help trying to jump on the bang wagon.
Then some guy post about how his heads with bronze guides only lasted 7000 miles in a 630 hp ish motor, from a crap company who obviously not only used softer guides, but put in some sand paper valves ta boot.
The highest miles reported here so far are from Khole on the m90 guides at 60,000 with no real wear present. Kohle owns the reliability record.
03-23-2017, 11:30 AM
#23
Moldstar without a doubt is a badass guide but most people just go with the pm guides for cost. However if he's testing those at 40k or more and they're still ok I think that's awesome. I should have been more specific in the sense that I meant mileage with their standard on guides
It does seem that a some of bronze guides wear out prematurely which could be as said from valves that don't have the proper coating and from lack of a RR
It does seem that a some of bronze guides wear out prematurely which could be as said from valves that don't have the proper coating and from lack of a RR
Last edited by redbird555; 03-23-2017 at 11:31 AM.
03-23-2017, 01:08 PM
#24
Team Owner
GM owns the reliability record. There have been a few z06s with 100k with in spec guides. So if that is your measure, stay stock.
03-23-2017, 01:14 PM
#25
03-23-2017, 03:53 PM
#26
A lot of people showed their true colors last week kicking a dog while it was down.
many cried how harder guides wont even help trying to jump on the bang wagon.
Then some guy post about how his heads with bronze guides only lasted 7000 miles in a 630 hp ish motor, from a crap company who obviously not only used softer guides, but put in some sand paper valves ta boot.
The highest miles reported here so far are from Khole on the m90 guides at 60,000 with no real wear present. Kohle owns the reliability record.
many cried how harder guides wont even help trying to jump on the bang wagon.
Then some guy post about how his heads with bronze guides only lasted 7000 miles in a 630 hp ish motor, from a crap company who obviously not only used softer guides, but put in some sand paper valves ta boot.
The highest miles reported here so far are from Khole on the m90 guides at 60,000 with no real wear present. Kohle owns the reliability record.
first up Lingenfelter reworked heads.
2nd up Livernois motorsports. with full roller rockers.
next up IPS motorsports
and this guy heads the valve stem is cracked..
all from one porter that was on this site 7 years ago warning you guys!
And if this is from one guy, let that sink in. there are more videos but these are the ones that really stood out to me
03-23-2017, 04:09 PM
#29
I just talked to Kohle today in prep for having him do a set of heads for me within the next 3 weeks or so. I didn't have this thread in mind nor did I take notes, so don't hold me accountable for accuracy. From what I remember, he said they'd checked valves and guides on heads after 40,000-50,000 miles- valves showed no measurable wear and the PM guides were within spec. I didn't ask for measurements. They have also checked heads with something like 60,000 miles with their Moldstar 90 guides and had no measurable wear on valves or guides. I hope that's accurate but I had an incoming call as he described that set and the audio on my phone gets cut off for a couple seconds when that happens. It's the mileage I'm not sure of but I think it's correct.
This much I'm sure of- he said the Moldstar 90s are definitely better guides, the same stuff used in F1, NASCAR, and Indy racing. He said that they are overkill for the street but if you're going to pound on your car at the track they will take the extra heat and abuse very well. That's what they're made for. Whether they're worth the extra $500 for your use is up to you.
Frankly, I haven't decided which guides I'll choose yet. I wish I'd taken notes but I figure some info is better than none. Hopefully Kohle will have time to stop in and verify what I've said.
This much I'm sure of- he said the Moldstar 90s are definitely better guides, the same stuff used in F1, NASCAR, and Indy racing. He said that they are overkill for the street but if you're going to pound on your car at the track they will take the extra heat and abuse very well. That's what they're made for. Whether they're worth the extra $500 for your use is up to you.
Frankly, I haven't decided which guides I'll choose yet. I wish I'd taken notes but I figure some info is better than none. Hopefully Kohle will have time to stop in and verify what I've said.
A lot of people showed their true colors last week kicking a dog while it was down.
many cried how harder guides wont even help trying to jump on the bang wagon.
Then some guy post about how his heads with bronze guides only lasted 7000 miles in a 630 hp ish motor, from a crap company who obviously not only used softer guides, but put in some sand paper valves ta boot.
The highest miles reported here so far are from Khole on the m90 guides at 60,000 with no real wear present. Kohle owns the reliability record.
many cried how harder guides wont even help trying to jump on the bang wagon.
Then some guy post about how his heads with bronze guides only lasted 7000 miles in a 630 hp ish motor, from a crap company who obviously not only used softer guides, but put in some sand paper valves ta boot.
The highest miles reported here so far are from Khole on the m90 guides at 60,000 with no real wear present. Kohle owns the reliability record.
Until there's a few thousand units in service with 60-100k + miles, there's no definitive answer that these heads fix anything anymore than any other head.
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FSTFRC (03-23-2017)
03-23-2017, 04:17 PM
#30
Safety Car
03-23-2017, 04:20 PM
#31
Safety Car
Use a credible shop so you don't get stuck with some crap heads that don't last.
Your case was the wrong valves installed with no coating or not polished.
Regardless, you make a great case against those whining harder valve guides wont help.
03-23-2017, 04:41 PM
#32
Great well since your a better builder than AI can I send them to you?
03-23-2017, 05:25 PM
#33
Safety Car
Sorry dude heads that only last 7000 miles even at 630hp ish, is still a mistake somewhere down the line.
They have a reputation for great power, not knocking the porting work.
And I don't know the full story, and since you didn't have the heads done the first time you may not know either.
03-23-2017, 07:25 PM
#34
The videos are great reference.
However one thing chad says in the first video I would like to know what he means.
What heads is he referring to when he calls it a 2.1 head at 1min 49secs - ie the one with no significant wear. Where does this head come from etc.
However one thing chad says in the first video I would like to know what he means.
What heads is he referring to when he calls it a 2.1 head at 1min 49secs - ie the one with no significant wear. Where does this head come from etc.
03-23-2017, 09:41 PM
#37
Really how many 100k miles AHP heads are there? How many 50K mile heads, how many 20K mile heads? Theres not enough of anyones heads in use to say the issue is resolved. Hell, I have no problems, is the issue resolved? IDK so that claim cant be made and its hardly BS
03-23-2017, 09:58 PM
#38
Safety Car
Factually Yes.
Stock engines with miles from new to old are dropping motors from valve failure when the head pops off.
Fixed engines have not dropped a valve ruining an engine to date. Suck on the fact for a bit will you
IDK
Obvious and it explains your answer.
there's plenty of stock headed cars surpassing 100K miles.
So if we improved the stock head dramatically, then the issue should be resolved by your own definition.
lets get into detail, the problem is dynamic. We are talking about stock motors in context here. Race engines is another talent and topic altogether.
#1 Factually the overall issue is out of spec guides from the factory.
#2 Soft guide material is wearing out quicker then normal due to no coating or polishing or micro hardening on the stock valve stems.
#3 it is an aggressive valve train, made worse with aftermarket cams.
early heads dropped exh valves and later motors were dropping int valves
Early heads had exh valves with uneven sides that broke.
SO if we address #1 and #2 the heads should last much longer. So stop your BS and stop the Absence of evidence fallacy.
03-23-2017, 10:05 PM
#39
Safety Car
Love ya brother
Oh and keep on rocking the Z, despite "our" BS were still brothers here trying to help the community at large.
Oh and keep on rocking the Z, despite "our" BS were still brothers here trying to help the community at large.
03-23-2017, 11:59 PM
#40
Race Director
I just talked to Kohle today in prep for having him do a set of heads for me within the next 3 weeks or so. I didn't have this thread in mind nor did I take notes, so don't hold me accountable for accuracy. From what I remember, he said they'd checked valves and guides on heads after 40,000-50,000 miles- valves showed no measurable wear and the PM guides were within spec. I didn't ask for measurements. They have also checked heads with something like 60,000 miles with their Moldstar 90 guides and had no measurable wear on valves or guides. I hope that's accurate but I had an incoming call as he described that set and the audio on my phone gets cut off for a couple seconds when that happens. It's the mileage I'm not sure of but I think it's correct.
This much I'm sure of- he said the Moldstar 90s are definitely better guides, the same stuff used in F1, NASCAR, and Indy racing. He said that they are overkill for the street but if you're going to pound on your car at the track they will take the extra heat and abuse very well. That's what they're made for. Whether they're worth the extra $500 for your use is up to you.
Frankly, I haven't decided which guides I'll choose yet. I wish I'd taken notes but I figure some info is better than none. Hopefully Kohle will have time to stop in and verify what I've said.
This much I'm sure of- he said the Moldstar 90s are definitely better guides, the same stuff used in F1, NASCAR, and Indy racing. He said that they are overkill for the street but if you're going to pound on your car at the track they will take the extra heat and abuse very well. That's what they're made for. Whether they're worth the extra $500 for your use is up to you.
Frankly, I haven't decided which guides I'll choose yet. I wish I'd taken notes but I figure some info is better than none. Hopefully Kohle will have time to stop in and verify what I've said.
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MTPZ06 (03-24-2017)