redbird555

Just wondering how many miles people have on their AHP heads. I've got their stage 4 package with PM guides as well as a 1511 and TI retainer/spring combo. Very happy with the whole process and the end product, I've currently got about 13k on mine now.

Lately on tech social media and even here I've seen some posts about some AI Lingenfelter and WCCH heads that have out of spec guides after very little miles with bronze guides. I still believe that bronze for the majority of us with stock rockers is a bad idea but that's another topic.

Still though it does make you think lol what kind of mileage do guys have here? Maybe Kohle could chime in about some cars he's seen come back and have the test redone after some use with his heads?

redbird555

Ttttt

sccaGT1racer

The valve guides are a wear item. When you introduce a harder guide material Does it just slow down the wear on the guide or does the valve stem wear? This is the million dollar question and only time will tell.

outhouse

Its not a million dollar question.


Guides wear more then valve stems wear.




Harder guides slow down the actual wear rate on the guide and the valve stem.

redbird555

Guides wear in every car yes but wearing them out at within a few thousand miles isn't normal for any car, when properly fixed an ls7 guide shouldn't wear any different than a normal car. Hence the op question. I believe there are some AHP heads with over 40k but I haven't seen much on those

sccaGT1racer

Where did this data come from because I would like to see it.

outhouse

Lifetime of racing.



What would you like to argue?


Valve stem material is harder then guide material, do you want to argue they wear at the same rate??


Softer material wears quicker then harder material.

Durien512

Life time of racing 4 cylinder cars in autoX events in parking lots does not count...

Fellow Cali dude here... its raining so I cant go play outside..

sccaGT1racer

"Harder guides slow down the actual wear rate on the guide and the valve stem."






With this logic you should make the guides out of the same material as the stem

FSTFRC

Ibtl!

outhouse

Context is key, no fallacies there.

outhouse

If you had your blue hat I would know you.

STANG KILLA SS

i would disagree. i have AHP moldstar 90 guides and stainless valves.

stainless is softer than both Ti and Steel. and M90 guides are harder than aftermarket PM guides.

redbird555

Ya guys the question here really isn't about guide wear. All guides will do that, however recently it's come up that some sets of WCCH heads have shown wear with bronze guides. We all know AHP pm is much harder than that. So I guess the question is how many miles do people have on their AHP heads and have they been checked? I'm not casting any doubt on the product, I think kohles heads are top notch. I was hoping he'd pop in here and give us some insight on what he's seen on his own heads he's pulled back apart over the years. Iirc some of them had over 30-40k

Using the excuse "all guides wear" is dumb IMO. Of course they wear but you don't see ls3 guides wearing out at 15k miles and I wouldn't expect a fixed ls7 head to either. But then again I've always been a firm believer that bronze has its place but it's not in a street car

outhouse

AHP states they had M90 guides checked at 60,000 miles with almost no wear at all.


My only point is the lubricity and corrosion resistance found of the harder guides causes less wear on the guide and valve. Its more then just hardness and context should have been obvious.


Where would you argue more wear is taking place, generally speaking???


Do you think you will wear your valve stems out before guides?

outhouse

You do understand many SS valves are coated and or treated for a form of micro hardness ?

nuke61

Does anyone have actual miles to report?

NW94Z

To answer the OP's question.

AHP Stage 4 heads.
Milled .02
Port and polished
Factory rockers
Ferrea exhaust valves
PSI 1511 springs w/ titanium retainers
Moldstar 90 guides
~2000 miles

Not especially helpful because of the low miles but I don't plan to ever have to address the heads again as long as I own the car. Time will tell.

jb78L-82

Your setup is what I am planning to do....99% street driven and if the stage 4 heads go 50-60,000 miles I would be thrilled...even more miles, even better.

Les

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.