Hey guys,
The 455 I recently built for my '71 Supreme (and installed last summer) is running mighty fine, even barking the tires at the 1-2 shift (200-4r) but I've been concerned about my valves. The J-heads I bought were ported, polished, bowl work, AIR bumps removed, spring seats deepened, all sharp corners removed in chambers, new guides, teflon seals, and had a three angle valve job. However, I wasn't able to get a great pattern on the valve stems. I'm running the CompCams roller tip rockers, guide plates, and studs and when working on the geometry with an adjustable push rod and checker springs, I couldn't get the pattern right without shortening the pushrods to the point where the rocker would gall the stud (riding too low). I figured the valve stems were ground down due to mushrooming (which wasn't disclosed during the sale) and I think I'm right. Anyway, even thought the engine is running very well, I pulled the covers to check. And I'm glad I did. The pattern is actually etching into the valve and the valve stem edges are looking chipped. I'm assuming they ground through the hardened tip, if that's possible.
So, to my question; Can I simply buy new valves and swap them in? I know I'll have to check the pattern again and more than likely need to buy new pushrods. Oddball says no, they should go to my machinist to be fit; and I respect his opinion. But can I fit them myself? Is it just a matter of lapping them in? OR, could I get away with lash caps for a time? I don't know if there is enough valve stem poking above the keepers for the caps.
Oh, if it matters, I have about 2k miles on these heads/valves. Also, the pattern in the pic is worse than what I was getting with the sharpy marker during the build but I was also giving them 3/4 turn preload and I've since changed that to 1/2 turn, not thinking about it affecting the pattern.
Thanks guys.

 

Yeah that pattern is pretty bad.
Have you machinist check the valves, then mill the rocker stud pads about .080-.100. That should help in the binding issue.

 

You don't think replacing the valves is a must? They look pretty bad to me but I don't have a lot of experience. They are definitely coved(?); lower in the center like they couldn't grind down all the mushroom. Which explains the shape of the pattern, I suppose.

And I'll see what he thinks about the milling the pads. Personally, I'd rather go higher with the valves and pushrods but milling might be cheaper.

Thanks Mark.

 

Tell me if I'm off base here but... the reason I can't get the correct geometry is the valves are shorter than they should be, requiring a shorter pushrod, which, when used, makes the rocker bind on the taper of the stud. Is there a non-tapered 3/8 stud I can use? Then it would just be a matter of measuring for the correct pushrods.
I'm going to have a look around.

 

Sounds like you have several different issues going on. Poor valve tip contact, short valves, mushroomed valve tips, binding/interference on rocker arm studs, incorrect rocker arm geometry. Are there any other things ?

 

What would cause poor valve tip contact? The roller tip rockers? I'm running .030" preload.

 

Preload isn't your problem. What has Cutlassefi told you ? What has your machinist told you ?

 

You can buy +.100 valves but those rocker kits are designed to work with the stock length valves. You have something else amiss.

 

Well sir, I guess that's my point; observations are telling me these are not stock-length valves. I wish I would have gotten some good pics and taken some measurements of the valves while I was changing the springs but, at the time, I hadn't considered the valve lengths would be an issue. I'm almost afraid to ask this but what would you think of running lash caps, only if I can get the pattern spot-on, while saving for some big valve iron or aluminum heads? Of course that would mean new pushrods.....

 

So I'm still dealing with the bad pattern issue. I understand what needs to happen; either take the heads to machinist for the new valves (or milling of the pads) or save for better heads (the more complete, the better). This weekend I pulled a few springs and took some measurements and the valve stems measure 0.360" in the middle and 0.355 at the tip. Am i correct that these are non-standard valves? I checked my caliper with a 2" anvil and it was off 001", and perfect with the 3" anvil. Either way, the valves measure out as non-standard.
So my thought was, in the interim, I might try putting the stock valve train back on to see what kind of pattern I get but can the stamped steel rockers handle .512 lift? And of so, the procedure would be to replace the rockers with stock (which I have), install checker spring and checker pushrod (which I also have), unscrew the pushrod until I feel resistance, and then add .030" length to get the recommended preload on the lifters. Then check the pattern. Does that sound about right?
It's quite possible that the pattern still won't be right, that is if the valves are too short.

 

I’d run the stock rockers and pushrods assuming the valve length is stock.

The valve length needs to be stock or it’s bad news.

 

[QUOTE=Macadoo;1193100valve stems measure 0.360" in the middle and 0.355 at the tip. Am i correct that these are non-standard valves?[/QUOTE]

Yes. If that is truly what they measure they are "rebuilder" valves that have .015" oversize stems. They are used by big rebuilders so that they do not have to replace (install) valve guides. They just run a special reamer through the guide to open it up to the new size The stock measurement is .343" Most of the time they are also a different head diameter and length to make up for worn out valve seats.

The biggest problem is once that junk has been installed in a head it makes it very time consuming ($$$) to put it back to original sizes.

Are they actually causing a problem the way they are other than the pattern looking off ?? If not, I would just run them the way they are until you can save up the money to do a correct set of heads. I have seen plenty of engines with the pattern a lot worse than that and they have run for many thousands of miles before I got to them. Probably the worse thing that will happen is they will wear out valve guides a little faster than normal but that really doesn't matter in this care anyway.

It does not look like there is enough room for lash caps but I will try to remember and measure one in the morning to see how deep the recess is in them.

 

Okay, no this is making a lot of sense. I thought I was wacky or something. The only difference is these heads do have new valve guides. I saw them when prepping the heads for install. They actually left a little bit of a ledge from the old seat that worried me. I had to pick off a few loose pieces from around the new guides. But yes, these must be the valves you describe.
Thanks for the advice. It's really what I was thinking; start socking money back while looking for some big valve C heads or comparable.
So, just to be clear, the only excessive wear will be in the heads. Nothing in the short block, correct?
Again, many thanks.

 

That makes no sense. Installing new valve guides with oversize stem valves ?????


Not sure what you mean by this ??? The valve guide and the valve seat are two totally different things.

[QUOTE=Macadoo;1193258]
So, just to be clear, the only excessive wear will be in the heads. Nothing in the short block, correct?
.[/QUOTE

Yes

 

Sorry Bill; yes, I meant I had to pick off some loose material from the leftover guide. My bad. Yesterday was a long day. I'll post a pic when I get home. But yeah, that doesn't make a lot of sense.

So, I'm okay with running this way, understanding that the guides (and really, therefor the heads) won't last quite as long but I looked for quite a while the last few evenings for lash caps but nothing I saw that would fit these valves. And considering that would more than likely involve the cost of new pushrods, add in the possibility that if something went wrong (bent pushrod) I could end up with a lash cap in my oil pan, I'm thinking twice about going that route.

 

Mac,
I just measured a lash cap and there is no way it will fit on the top of the valve without hitting the locks and retainer. I would just run it like it is till you get the funds to do it right. It might surprise you and run a long time like that

 

Well sir, right now I put about 1k miles on it a year; not a ton. But one day we might like to take it out west and test out this four-row radiator, lol.

My understanding is that lash caps require recessed, 10* locks, which would be another expense. My concern is finding .360" caps, which I don't think are available. Again, at this point, it may be a non issue. I have a friend offering me some Ga heads if I pay shipping. They're just cores but it's a start.

Here's that pic of the guides:

 

Not sure why the springs were shimmed (with rusty shims) but I replaced the springs, anyway, with the correct springs for my cam.

 

Mac,
I have a feeling that you are not measuring the valve properly. Even the oversize stem valves are the correct size at the top where the keepers go so they should measure right about .343" plus or minus a little. If they put guides in, which it looks like they did, then I doubt that you have oversize valves. They could have done a little neater job with the guides for sure

 

Who did the work on the heads ? They should know what they used for parts and what work they performed.

 

Good point. My digital caliper isn't the most expensive unit. But I did verify the difference using a couple anvils from my micrometer (which is a used high end brand). But I can be fairly certain that these valves aren't going to measure 0.3125 (5/16) or 0.375 (did these motors even use 3/8" valves?).

Another good idea. However, the dude I bought them from (the heads) was an elderly machinist that closed up shop and retired (a couple hours from where I'm located). He seemed like a good guy. We talked for hours when I picked them up. He even pulled a couple springs to show me the teflon seals and pointed out the bowl work, where he took off the AIR bumps, etc. Had I known more at the time, I would have asked about the valves. I'll email him but won't expect a response.

 

The valves are supposed to be 11/32 which is about .343" They will vary some. The exhaust valves are typically a little smaller than the intakes for more guide clearance.

 

If the valves were new they would probably have a part number on them up near the top of the stem but you would have to pull a spring to see it.

 

 

"Standards", yes. At least I was in the ballpark, lol. So, the +.015, is that the tolerance? Either way, it's sounds like my valves are 11/32.

Okay then, as for the guides; I tested the valves for tightness in the guides before install but not correct angle or location. So here's the current plan; I'm going to buy a lash cap or two, 11/32, and with the checker springs and adjustable pushrod, check for pattern. Although I'll have to check to see if I can get only one or two sets of recessed, 10* locks. If can get a good pattern with the caps and appropriate length pushrods, I'll look at going that route.

I get where the pattern should be located but what effects the thickness of the pattern; or thin-ness? Is that controllable? It should be as thin as possible, yes?

 

Mac,

The lash caps will not work. I tried a couple of them on a set of 350 Olds heads I just finished and the recess in them is way too deep. They will hit on the valve locks which would be catastrophic. You cannot use the 10 degree locks with the stock retainers. You will have to buy an entire set of aftermarket 10 degree retainers and locks.

Believe me when I say that your best course of action right now is to run it the way it is. It is probably better than it ever was from the factory anyway Even with your slightly offset pattern it will probably go 80,000 miles before it makes a difference.

You are worrying way to much about something that you cant really do anything about unless you want to completely redo the heads correctly.

 

 

Yeah man, I'm just going to run it the way it is and start saving for some aluminum heads maybe down the road.

If the valves have been ground down I believe it would effect the pattern but it's a non-issue at this point. If the pattern being off isn't going to effect the short block, I'm not going to worry about it for now.

I didn't realize I'd need new retainers also. Add in the price of new pushrods and I'm beyond what I want to put into a band-aid fix. And Summit only sells all this stuff in quantities of 16 anyway; no way to check before I commit.

Thanks for all the input, fellas. This has been a good thread with good information. And @Ralph; call me on my vocabulary anytime. We don't need to muddy the waters with improper language. Enough of that going around already. "Four core radiators" instead of four row. Drives me crazy, lol.

 

 

Mac.... say I have access to a lathe and could possibly turn down your rocker arm studs a hair. I don't think you are running enough spring pressure to hurt the studs if we remove some material from the stem. Plus your rocker arm would be much lower on the stud eliminating some flex.

 

Now this is just another thought. What about a pedestal mount rocker arm from a ford. They are adjustable from underneath with shims . possible cheap way out ? https://www.summitracing.com/parts/p...view/make/ford

 

@Ralph; Agreed!

I thought about this and even had a look at the studs. I have a homemade lathe setup for my drill press (not great on the bearings but it works). But the galling is wayyy down the stud, near the hex. Just not enough room.

So you think these might sit lower, and with the correct pushrods could correct the geometry? Interesting..... plus they look way cooler! But if Ralph's correct, and there are , indeed, other issues, it might not help. And I am still concerned about the faces the stems (faces?). It's easy to see that they have been ground down; and on some, not ground down enough to make them flat. The roller tips are wearing on the outside of the face and not touching the interior, at least on some of the valves. I really think it's time to start saving for some other heads. Justin offered me some Ga head cores but the Olds Faq says they can be hard to find valves for. And shipping would be $95.....per head. Utah is more than a hop, skip, and jump from Illinoiz

 

Why not consider Procomp heads?

 

Should I start a fund-me page?

Seriously, I'd like them to be in the running. Just depends on how much I can save before these start to show issues, I suppose/

 

Mac I think my buddy may have a set in Indiana. Irons but should work out.