Slant Six Bumblebee
Well-Known Member
Just took apart my cylinder head today and was wondering if everything looks normal.
Slant six head
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Just took apart my cylinder head today and was wondering if everything looks normal.
How many miles are on the engine, and what are the rest of the particulars on it (intake, exhaust, carb, cam)?
Slant Six Bumblebee
Well-Known Member
I am unsure of the miles it was a running engine when i took it apart and is stock as far as i know. the odo says 21000 so i think 121000 but i think the head was rebuild around 10k ago
Slant Six Bumblebee
Well-Known Member
I am woried that the valve seats are leaking as i am planing to get a backcut on the stock valves and keep them.
Yeah looks normally worn out and nasty. lol
Did you feel the guide and valve stem wear? Put a dial indicator on the side of the valve head and see how much lateral movement back and forth you get. It looks like the intake has been sucking oil past the seals and guides.
Slant Six Bumblebee
Well-Known Member
there was also a major oil lean on cylinder 1 and 2 because it was missing a head bolt
Cross your fingers it's not broken off. The valve job looks worn slam out too.there was also a major oil lean on cylinder 1 and 2 because it was missing a head bolt
Slant Six Bumblebee
Well-Known Member
it was not broken off just someone forgot to reinstall it.
Wdym that valve job looks worn slam out>
Look at the seats and the valve faces. See those pits? Needs a valve job terribly. Might need guides too. Possibly seats....Machine shop can tell you for sure.
Slant Six Bumblebee
Well-Known Member
If i do a valve job would it be more cost efective to go with bigger valves and where do i buy such valves
my68barracuda
Well-Known Member
Hughes Engines has OS valves that drop into a slant six, same length and stem diameter, however they are pricy.
Many folks go with other Chevy or Ford valves, as they will have thinner stems and the valves are cheaper. But then one needs new locks and retainers. Longer valve stems can lead to valve train geometry issues. Those are fixable but that is also more money.
The stock sized valves with a good multi angle valve seat job can work for you depending upon the performance goals for the motor.
IIRC you are planning a low cost turbo build using a stock cam. If that is correct, I would stay with the stock valves, get a good multi angle valve seat job, a bowl clean up and the back cut that you have mentioned.
I would definitely put in new guides and with a turbo I would install positive valve seals. Your machine shop will need to trim the od of the valve guides to get positive valve seals to fit.
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Slant Six Bumblebee
Well-Known Member
If I am reading this correctly you say keep the stock size valves and just get new ones while also getting positive valve seals valve guides and a valve job on the stock seats
And for stock replacement valves I see valves on rock auto by enginetech part numbers v1349 and v1350 are those what I want and then use stock springs and retainers and positive valve seals that are 3/8x.562
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I bought my OS valves from Oregon cams when I had my cam out there for a regrind. As I remember they were a buck or 2 each cheaper than Hughes. I don't remember the brand of the valves they sent me. Might have been the SI brand, I've since heard may not be being made any more. Stock /6 length and stem diameter
Slant Six Bumblebee
Well-Known Member
Did you use valve guides if so what material because i see iron valve guides for sale on rock auto but i have seen people talk about bronze valve guides being the way to go.
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my68barracuda
Well-Known Member
Yes, keep the stock sized valves and install new valve guides and positive valve seals.
I would definitely let the machine shop doing the work source the valve guides and positive valve seals.
Have the MS quote both bronze and iron guides and then see if the price difference is worth it to you. Billions of motors have used iron guides for billions of miles.
I would also let the MS quote the valves, and the springs and the keepers. they can likely buy as cheaply as you can.
Your existing retainers should be good for re use. If you are putting in new valves I would put in new keepers.
Ask the shop to itemize all the parts on the estimate. You need to already have a good idea of what you can buy the parts for. Then you can make a comparison of the MS part pricing to what you can buy the parts for. A good shop may put a small over charge on the ordered parts to cover the time they have invested in the ordering, stocking,,, but if they are laying it to you, that is a good reason to find another MS to work with.
About the only time I bring parts to a machine shop is when I am using valves / springs / retainers or other components that are not stock but that is what I want.
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I don't know if they had to replace the guides in that head. I had told the machine shop to do so, if necessary. They didn't say anything about it either way. Though when I took this head in, I already had my OS valves and brought them in with it. Mine was a "whenever they get to it" back burner job. which I was OK with. But I also brought them a sheet that I typed up and printed off the computer (cuz I even sometimes have trouble reading my own scratch and scrawl) telling them some things I wanted done "no matter what" to that head.
I stopped by periodically, and we called back n forth with updates along the way, and every time they said they had "this part" done, I asked if they did something along the way that would involve "that part" of the job. and each time they acted surprised that I wanted what I was asking if they had done; things like.... I brought in oversized valves, it goes without saying that they would have to make the seats bigger, to accomodate..... which was a good thing because of all of my "slips" with the die grinder I had toasted a few of the original seats. But when I reminded them that I wanted hardened seats put in-- at least on the exhausts--- they came back with "we have the seats cut, they'll be fine" I said; "No, I want hardened seats cut out for, and pressed into this head". They resisted (because it meant a little bit of a back track) but finally agreed to do as I asked.
same thing happened again, when I asked if they'd cut down the tops of the guides, because I put in a larger than stock cam, and I didn't want the bottoms of the retainers to crash.
I don't know if they cut in a single angle seat, or a 3 angle seat. I do know, that they finished my start to a porting job/ and they magnafluxed it when done, to be sure that nobody "hit water" while porting..... neither I did or they did.... and that came up good.
when all was done I know I didn't get a printed out reciept that itemized what they did do.... just told me how much cash to bring them and they wrote me a "cash reciept" out of a generic reciept book that I think can even be bought at places like Walmart....
and the goofy part? that sheet that I handed them when I brought them the head was sitting right there on the bench right next to where they had been working on it when I picked the head up.
I have used these guys before, and I have never had a problem with anything they have done for me, prior to the machine work on this head/ and everything that I measured out to "check their work" on the block portion of this project, while I was assembling it, came out great. and they did go to extra measures to make sure that a questionable "line" on the block we both questioned, was a casting mark/flaw and not a crack.. they sent it out to be sonic tested and shot blasted over and above what I had asked them to do. I did the block and head as 2 seperate deals, one right after the other.
oh... and as manufactured originally, the "valve guides" on these heads, are just reamed passages in the parent casting.
The machine shop would have to ream them oversize enough to press a guide into the head, if wear limits would necessitate that. A "valve guide" is a "sleeve" that the MS would put into the head.
back in the day they used to sell valves with stems a few thousandths fatter than stock, as "service valves," and they would just directly ream the existing guide that much oversize to "square up" and make them truly round again.
I'd leave the "does it need new guides" and if so "what material" up to the machine shop. and if it winds up needing them, I'd do at least all the intakes or all the exhausts at that point.... if not the whole head. I don't know that I'd want just 1 or 2 valves in a given head with the guides replaced and not the rest.
The machine shop would have to ream them oversize enough to press a guide into the head, if wear limits would necessitate that. A "valve guide" is a "sleeve" that the MS would put into the head.
back in the day they used to sell valves with stems a few thousandths fatter than stock, as "service valves," and they would just directly ream the existing guide that much oversize to "square up" and make them truly round again.
I'd leave the "does it need new guides" and if so "what material" up to the machine shop. and if it winds up needing them, I'd do at least all the intakes or all the exhausts at that point.... if not the whole head. I don't know that I'd want just 1 or 2 valves in a given head with the guides replaced and not the rest.
on positive seals, there are many that will fit, even though not "listed for that application". I had bought mine via Ebay, think I paid ~$10 for a set, that was said in the listing heading as being "for" a slant 6. I had taken in both styles (positive and stock style umbrella) and said to use whichever ones they felt more appropriate, and I can see that they put in the positive style seals.
That said I know they have a drawer full of random ones, I did some work on a twin cyl Kohler and took my old ones in, (what was left of them) and they "matched some up" for me, handed them to me and said "have a nice day". Kohler wanted something stupid like $18 each and there are 4 of them on that particular engine. Your machine shop of choice probably has plenty on hand, as well.
That said I know they have a drawer full of random ones, I did some work on a twin cyl Kohler and took my old ones in, (what was left of them) and they "matched some up" for me, handed them to me and said "have a nice day". Kohler wanted something stupid like $18 each and there are 4 of them on that particular engine. Your machine shop of choice probably has plenty on hand, as well.
Dorian
dorian
So for a buck or two per valve are the Hughes valves better? I have a Hughes Stroker kit and am very happy with it. I would think for an extra 24.00 I would go with Hughes
Slant Six Bumblebee
Well-Known Member
that is still way more expensive then stock replacement valves with a valve job
well since Hughes rebrands everything as their own, I'd bet that you're buying the exact same valves I got, just with a higher price tag.
I know this is a slightly outdated example, (since these smallblock Magnum heads are currently not able to be had) but when I bought mine straight from EQ they were alot cheaper than buying them from Hughes. Without having them do any additional work to them besides how they come "out of the box". Only difference was Hughes called them "Iron Ram" heads. It was a well known fact that they were the exact same heads.
Now if the product Hughes sells is somehow a different product than what I got? I can't say for sure in this case. I know I got a well known name brand and not a private label rebrand. just like with brakes and other parts I get from places like Oreilly I never settle for the house brand because of the "unknown" factor. You know that Oreilly is just a reseller and they don't actually make anything, and I feel more comfortable with a known brand than someone's "house brand" if I know nothing more about theirs vs the name brand. It isn't about "only $24 more". and I don't remember exactly how much difference there was (I can look and see, if someone really wants to know the brand and price of what I got from Oregon Cams, I have the reciept stashed, from buying them) the figure i put up, was approximate/
now if you're buying other stuff from Hughes and it's more convenient to just tack them on your order while you're there, I get that, too. That was largely why I went ahead and got mine from Oregon because they had to ship me my reground cam back "anyways," at the time.
but your engine being able to breathe better than a stock head, makes that "worth it". There has been lots written here about the benefits vs cost of oversized valves on a /6 especially a 225 version. as the original heads were made, they were still as-designed for a 170," and just slapped on the 225.
I used stock 318 valves in my head. I did that for a couple of reasons. Primarily because at the time, no one had the obligatory 1.70 and 1.44 over sized slant 6 valves. Also, because the 318 valves are bigger. lol If you do that, you will need to contact Mike at @B3 Racing engines to get your rocker shaft relocated, as the 318 valves are .300" longer then the slant 6 valves and require relocating the rocker shaft to correct geometry. There are other options that don't require "all that", but in my situation, that was the quickest and easiest thing so I did it. That's just a decision you'll have to make.
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