Valve tip wear after cam and springs upgrade
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rmcomprandy
OlDirty
6 posters
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Valve tip wear after cam and springs upgrade
I own a 1969 Tbird with a 429cu.
After a good conversation with Randy (RM Competition), I upgraded to a Lunati Voodoo Cam and Lifter Kit 10340701LK and COMP Cams Valve Springs #926-16 about 3k mls ago.
I know that Randy is one of the most reputable and knowledgable BBF guys out there, so I have no doubt, that these components were a good upgrade for my usage profile.
My usage profile is "street only" in Germany (where you may go as fast as you want on some parts of the "Autobahn", what I rarely do with the Tbird)
After removing heads (C9VE) due to a head gasket leak I found that the exhaust valve tips have suffered from excessive wear. So there must've been something wrong in the rest of my setup.
Lifters and cam still look good.
I already learned, that the easiest fix would be to add lash caps and/or roller rockers.
What's your recommendation?
Lash caps only or are roller rocker arms mandatory too?
When installing lash caps, the valves would need to be shortened by the exact amount of the lash cap thickness, correct?
Are there any roller rockers that don't require any mentionable modification or none at all on the C9VE heads?
Thank you!
After a good conversation with Randy (RM Competition), I upgraded to a Lunati Voodoo Cam and Lifter Kit 10340701LK and COMP Cams Valve Springs #926-16 about 3k mls ago.
I know that Randy is one of the most reputable and knowledgable BBF guys out there, so I have no doubt, that these components were a good upgrade for my usage profile.
My usage profile is "street only" in Germany (where you may go as fast as you want on some parts of the "Autobahn", what I rarely do with the Tbird)
After removing heads (C9VE) due to a head gasket leak I found that the exhaust valve tips have suffered from excessive wear. So there must've been something wrong in the rest of my setup.
Lifters and cam still look good.
I already learned, that the easiest fix would be to add lash caps and/or roller rockers.
What's your recommendation?
Lash caps only or are roller rocker arms mandatory too?
When installing lash caps, the valves would need to be shortened by the exact amount of the lash cap thickness, correct?
Are there any roller rockers that don't require any mentionable modification or none at all on the C9VE heads?
Thank you!
OlDirty- Posts : 8
Join date : 2023-06-15
Re: Valve tip wear after cam and springs upgrade
Those exhaust valves NEED some kind of hardened tip.
Most exhaust valves already have them manufactured on them. Those that don't need to use some kind of hardened lash cap.
There will be no problem using stock rocker arms IF the geometry is near correct.
Now, using a "lash cap" cam be tricky. First, the valve tips need to be flat but, don't necessarily need to be shortened.
It is all about getting the geometry to be correct.
A stock rocker arm without a roller tip uses a wide tip pattern starting toward the inside of the valve tip and "rolling" toward the outside of the valve tip at maximum valve lift; scrubbing that tip the least amount as can be. Totally DIFFERENT than a roller tip rocker arm.
There is no issue using a lash cap with a solid lifter but, when using a hydraulic lifter, things have to be just right.
The lifter plunger travel NEEDS to be set near the bottom of the lifter plunger travel. The reason being ... IF the lifter plunger can depress more than .040" when running, the valve train can "spit" the lash cap off the valve tip.
Personally, I would simply buy new exhaust valves which have a hardened tip.
Most exhaust valves already have them manufactured on them. Those that don't need to use some kind of hardened lash cap.
There will be no problem using stock rocker arms IF the geometry is near correct.
Now, using a "lash cap" cam be tricky. First, the valve tips need to be flat but, don't necessarily need to be shortened.
It is all about getting the geometry to be correct.
A stock rocker arm without a roller tip uses a wide tip pattern starting toward the inside of the valve tip and "rolling" toward the outside of the valve tip at maximum valve lift; scrubbing that tip the least amount as can be. Totally DIFFERENT than a roller tip rocker arm.
There is no issue using a lash cap with a solid lifter but, when using a hydraulic lifter, things have to be just right.
The lifter plunger travel NEEDS to be set near the bottom of the lifter plunger travel. The reason being ... IF the lifter plunger can depress more than .040" when running, the valve train can "spit" the lash cap off the valve tip.
Personally, I would simply buy new exhaust valves which have a hardened tip.
Last edited by rmcomprandy on June 30th 2023, 11:43 am; edited 1 time in total
stanger68 and OlDirty like this post
Re: Valve tip wear after cam and springs upgrade
Thank you for the reply Randy!rmcomprandy wrote:
Personally, I would simply buy new exhaust valves which have a hardened tip.
Which stock size exhaust valves would you recommend?
These are the original specs:
OlDirty- Posts : 8
Join date : 2023-06-15
Re: Valve tip wear after cam and springs upgrade
OlDirty wrote:Thank you for the reply Randy!rmcomprandy wrote:
Personally, I would simply buy new exhaust valves which have a hardened tip.
Which stock size exhaust valves would you recommend?
These are the original specs:
Those specs SAY "hardened foot" which it seems that yours don't have.
There are many companies who offer replacement valves. Melling, QualCast, Elgin are just a few.
Last edited by rmcomprandy on June 30th 2023, 11:51 am; edited 1 time in total
Re: Valve tip wear after cam and springs upgrade
This is the original AMA spec sheet from FoMoCo issued 10-1-68. But yes, my exhaust valves seem not to be hardened. Otherwise they wouldn't look like that.
OlDirty- Posts : 8
Join date : 2023-06-15
Re: Valve tip wear after cam and springs upgrade
They probably where hardened, they have just worn out over time.
Plus the elevated spring pressures and performance lobes on the cam don’t help when something is used and older already
If your going to pull the heads and work on them, consider some SS replacement valves and or hardened seats for the unleaded gas nowdays.
Plus the elevated spring pressures and performance lobes on the cam don’t help when something is used and older already
If your going to pull the heads and work on them, consider some SS replacement valves and or hardened seats for the unleaded gas nowdays.
dfree383- BBF CONTRIBUTOR
- Posts : 14852
Join date : 2009-07-09
Location : Home Wif Da Wife.....
Re: Valve tip wear after cam and springs upgrade
My first thought was the pushrod length. Maybe too long? If they are just slightly longer/shorter, the hyd. lifter will usually compensate for it, but if it's too much or too little, you're going to have problems.
BBFTorino- Posts : 999
Join date : 2015-12-31
Re: Valve tip wear after cam and springs upgrade
Any idea why the head gasket failed after 3K miles on a rebuild?
Where the block and or heads surfaced?
If so any idea how much?
What length pushrods?
Rail Rockers I "assume"? Are they Worn also?
Some machinists will resurface the valve tips to keep the same installed height with a valve job. Maybe they cut through the temper, or as has already been said worn through with use?
That is a sharp looking Thunderbird. Have you Topped it out on the Bond and what did she do?
Where the block and or heads surfaced?
If so any idea how much?
What length pushrods?
Rail Rockers I "assume"? Are they Worn also?
Some machinists will resurface the valve tips to keep the same installed height with a valve job. Maybe they cut through the temper, or as has already been said worn through with use?
That is a sharp looking Thunderbird. Have you Topped it out on the Bond and what did she do?
supervel45- Posts : 4502
Join date : 2013-09-04
Re: Valve tip wear after cam and springs upgrade
Pushrods were still stock. There hasn'bt been any modifications to the engine besides another carb, cam, lifters and springs.BBFTorino wrote:My first thought was the pushrod length. Maybe too long? If they are just slightly longer/shorter, the hyd. lifter will usually compensate for it, but if it's too much or too little, you're going to have problems.
I'm pretty sure heat was the issue.supervel45 wrote:Any idea why the head gasket failed after 3K miles on a rebuild?
Where the block and or heads surfaced?
If so any idea how much?
What length pushrods?
Rail Rockers I "assume"? Are they Worn also?
Some machinists will resurface the valve tips to keep the same installed height with a valve job. Maybe they cut through the temper, or as has already been said worn through with use?
That is a sharp looking Thunderbird. Have you Topped it out on the Bond and what did she do?
Nothing had been resurfaced yet. But heads will be resurfaced as little as possible now.
Pushrods are stock length.
I'm not a native speaker, but I assume you mean the rocker arms?! They all look like that:
My engine builder says they're fully hardened. He wants to resurface the valve tips and cylinder heads, do a valve job and then I should reassemble the engine again. The idea is, that by taking away a small amount from the valve tips, they become shorter, thus pressure will be reduced. He's a reputable engine guy over here (Germany), but US engines are not every day business of course. Hope his idea will turn out well.
Thanks. A lot of work has gone into it already. Has also been featured in a large German classic car magazine lately.
What do you mean with "Have you Topped it out on the Bond?"?
OlDirty- Posts : 8
Join date : 2023-06-15
Re: Valve tip wear after cam and springs upgrade
OlDirty wrote:Pushrods were still stock. There hasn'bt been any modifications to the engine besides another carb, cam, lifters and springs.BBFTorino wrote:My first thought was the pushrod length. Maybe too long? If they are just slightly longer/shorter, the hyd. lifter will usually compensate for it, but if it's too much or too little, you're going to have problems.I'm pretty sure heat was the issue.supervel45 wrote:Any idea why the head gasket failed after 3K miles on a rebuild?
Where the block and or heads surfaced?
If so any idea how much?
What length pushrods?
Rail Rockers I "assume"? Are they Worn also?
Some machinists will resurface the valve tips to keep the same installed height with a valve job. Maybe they cut through the temper, or as has already been said worn through with use?
That is a sharp looking Thunderbird. Have you Topped it out on the Bond and what did she do?
Nothing had been resurfaced yet. But heads will be resurfaced as little as possible now.
Pushrods are stock length.
I'm not a native speaker, but I assume you mean the rocker arms?! They all look like that:
My engine builder says they're fully hardened. He wants to resurface the valve tips and cylinder heads, do a valve job and then I should reassemble the engine again. The idea is, that by taking away a small amount from the valve tips, they become shorter, thus pressure will be reduced. He's a reputable engine guy over here (Germany), but US engines are not every day business of course. Hope his idea will turn out well.
Thanks. A lot of work has gone into it already. Has also been featured in a large German classic car magazine lately.
What do you mean with "Have you Topped it out on the Bond?"?
I meant top speed you may have attained on the non restricted part of the highway.
Rail Rocker is the style of rocker arm you have. It was used from 1968 to 1971 on 429/460 non high performance engines like yours. The two rails on the valve side aligns the rocker arm, to the valve tip, so as guide plates are not required, to keep them aligned.
If it was my engine, I would replace the valves with stainless ones, or new hardened ones, as suggested.
I don't know how much you can cut the valve tip before the rail on the rocker starts hitting the keeper but, I would keep a close eye on that, if you reuse your old valves.
How bad did you over heat it to blow the head gasket?
Does it have a temperature gauge or an Idiot Light only?
How is cutting the valve tips going to lower pressure?
Not much info provided on the head gasket leak. I would inspect the block deck very closely, and put a straight edge across it to make sure all is well. Use good gaskets, maybe roughen up the deck, and clean all surfaces with acetone.
If you ever drop a valve and take out a piston, and or cylinder head or block, or all 3, on a performance leaning rebuilt engine, you will never likely scrimp on cheap or used valves again.
supervel45- Posts : 4502
Join date : 2013-09-04
Re: Valve tip wear after cam and springs upgrade
rmcomprandy wrote:Those exhaust valves NEED some kind of hardened tip.
Most exhaust valves already have them manufactured on them. Those that don't need to use some kind of hardened lash cap.
There will be no problem using stock rocker arms IF the geometry is near correct.
Now, using a "lash cap" cam be tricky. First, the valve tips need to be flat but, don't necessarily need to be shortened.
It is all about getting the geometry to be correct.
A stock rocker arm without a roller tip uses a wide tip pattern starting toward the inside of the valve tip and "rolling" toward the outside of the valve tip at maximum valve lift; scrubbing that tip the least amount as can be. Totally DIFFERENT than a roller tip rocker arm.
There is no issue using a lash cap with a solid lifter but, when using a hydraulic lifter, things have to be just right.
The lifter plunger travel NEEDS to be set near the bottom of the lifter plunger travel. The reason being ... IF the lifter plunger can depress more than .040" when running, the valve train can "spit" the lash cap off the valve tip.
Personally, I would simply buy new exhaust valves which have a hardened tip.
I’m with randy on this one. You really should buy new valves. They dont cost that much. You are flirting with disaster shortening the tips using rail type rockers.
stanger68- Posts : 502
Join date : 2015-12-05
Location : Birmingham, Al
Re: Valve tip wear after cam and springs upgrade
stanger68 wrote:rmcomprandy wrote:Those exhaust valves NEED some kind of hardened tip.
Most exhaust valves already have them manufactured on them. Those that don't need to use some kind of hardened lash cap.
There will be no problem using stock rocker arms IF the geometry is near correct.
Now, using a "lash cap" cam be tricky. First, the valve tips need to be flat but, don't necessarily need to be shortened.
It is all about getting the geometry to be correct.
A stock rocker arm without a roller tip uses a wide tip pattern starting toward the inside of the valve tip and "rolling" toward the outside of the valve tip at maximum valve lift; scrubbing that tip the least amount as can be. Totally DIFFERENT than a roller tip rocker arm.
There is no issue using a lash cap with a solid lifter but, when using a hydraulic lifter, things have to be just right.
The lifter plunger travel NEEDS to be set near the bottom of the lifter plunger travel. The reason being ... IF the lifter plunger can depress more than .040" when running, the valve train can "spit" the lash cap off the valve tip.
Personally, I would simply buy new exhaust valves which have a hardened tip.
I’m with randy on this one. You really should buy new valves. They dont cost that much. You are flirting with disaster shortening the tips using rail type rockers.
AND, by looking at the photos, it looks like some rail rockers have been touching the valve locks or retainer already.
Mark Miller likes this post
Re: Valve tip wear after cam and springs upgrade
Top speed so far was 130mph, then I got scared LOL. Suspension is still stock. Most components new, but stock...supervel45 wrote:OlDirty wrote:Pushrods were still stock. There hasn'bt been any modifications to the engine besides another carb, cam, lifters and springs.BBFTorino wrote:My first thought was the pushrod length. Maybe too long? If they are just slightly longer/shorter, the hyd. lifter will usually compensate for it, but if it's too much or too little, you're going to have problems.I'm pretty sure heat was the issue.supervel45 wrote:Any idea why the head gasket failed after 3K miles on a rebuild?
Where the block and or heads surfaced?
If so any idea how much?
What length pushrods?
Rail Rockers I "assume"? Are they Worn also?
Some machinists will resurface the valve tips to keep the same installed height with a valve job. Maybe they cut through the temper, or as has already been said worn through with use?
That is a sharp looking Thunderbird. Have you Topped it out on the Bond and what did she do?
Nothing had been resurfaced yet. But heads will be resurfaced as little as possible now.
Pushrods are stock length.
I'm not a native speaker, but I assume you mean the rocker arms?! They all look like that:
My engine builder says they're fully hardened. He wants to resurface the valve tips and cylinder heads, do a valve job and then I should reassemble the engine again. The idea is, that by taking away a small amount from the valve tips, they become shorter, thus pressure will be reduced. He's a reputable engine guy over here (Germany), but US engines are not every day business of course. Hope his idea will turn out well.
Thanks. A lot of work has gone into it already. Has also been featured in a large German classic car magazine lately.
What do you mean with "Have you Topped it out on the Bond?"?
I meant top speed you may have attained on the non restricted part of the highway.
Rail Rocker is the style of rocker arm you have. It was used from 1968 to 1971 on 429/460 non high performance engines like yours. The two rails on the valve side aligns the rocker arm, to the valve tip, so as guide plates are not required, to keep them aligned.
If it was my engine, I would replace the valves with stainless ones, or new hardened ones, as suggested.
I don't know how much you can cut the valve tip before the rail on the rocker starts hitting the keeper but, I would keep a close eye on that, if you reuse your old valves.
How bad did you over heat it to blow the head gasket?
Does it have a temperature gauge or an Idiot Light only?
How is cutting the valve tips going to lower pressure?
Not much info provided on the head gasket leak. I would inspect the block deck very closely, and put a straight edge across it to make sure all is well. Use good gaskets, maybe roughen up the deck, and clean all surfaces with acetone.
If you ever drop a valve and take out a piston, and or cylinder head or block, or all 3, on a performance leaning rebuilt engine, you will never likely scrimp on cheap or used valves again.
I will try to convince my engine machinist of SS valves.
It has a gauge. The radiator went bad on a warm day.
I thought, when the valve is shorter, the rocker would have more "space" thus pressing less on the valve. But after overthinking that, it makes no sense regarding the geometry. Right?
Which gasket manufacturer would you use? Was thinking about Cometic, but probably a bit too much for my usage. Normally I choose FelPro.
Yes, again, I will try to convince my machinist.stanger68 wrote:rmcomprandy wrote:Those exhaust valves NEED some kind of hardened tip.
Most exhaust valves already have them manufactured on them. Those that don't need to use some kind of hardened lash cap.
There will be no problem using stock rocker arms IF the geometry is near correct.
Now, using a "lash cap" cam be tricky. First, the valve tips need to be flat but, don't necessarily need to be shortened.
It is all about getting the geometry to be correct.
A stock rocker arm without a roller tip uses a wide tip pattern starting toward the inside of the valve tip and "rolling" toward the outside of the valve tip at maximum valve lift; scrubbing that tip the least amount as can be. Totally DIFFERENT than a roller tip rocker arm.
There is no issue using a lash cap with a solid lifter but, when using a hydraulic lifter, things have to be just right.
The lifter plunger travel NEEDS to be set near the bottom of the lifter plunger travel. The reason being ... IF the lifter plunger can depress more than .040" when running, the valve train can "spit" the lash cap off the valve tip.
Personally, I would simply buy new exhaust valves which have a hardened tip.
I’m with randy on this one. You really should buy new valves. They dont cost that much. You are flirting with disaster shortening the tips using rail type rockers.
I would really love to upgrade to roller rockers, but am totally unsure what machining needs to be done. Larger studs after drilling and tapping the head is not a problem. But what else on my C9VE heads?rmcomprandy wrote:stanger68 wrote:rmcomprandy wrote:Those exhaust valves NEED some kind of hardened tip.
Most exhaust valves already have them manufactured on them. Those that don't need to use some kind of hardened lash cap.
There will be no problem using stock rocker arms IF the geometry is near correct.
Now, using a "lash cap" cam be tricky. First, the valve tips need to be flat but, don't necessarily need to be shortened.
It is all about getting the geometry to be correct.
A stock rocker arm without a roller tip uses a wide tip pattern starting toward the inside of the valve tip and "rolling" toward the outside of the valve tip at maximum valve lift; scrubbing that tip the least amount as can be. Totally DIFFERENT than a roller tip rocker arm.
There is no issue using a lash cap with a solid lifter but, when using a hydraulic lifter, things have to be just right.
The lifter plunger travel NEEDS to be set near the bottom of the lifter plunger travel. The reason being ... IF the lifter plunger can depress more than .040" when running, the valve train can "spit" the lash cap off the valve tip.
Personally, I would simply buy new exhaust valves which have a hardened tip.
I’m with randy on this one. You really should buy new valves. They dont cost that much. You are flirting with disaster shortening the tips using rail type rockers.
AND, by looking at the photos, it looks like some rail rockers have been touching the valve locks or retainer already.
OlDirty- Posts : 8
Join date : 2023-06-15
Re: Valve tip wear after cam and springs upgrade
C9VE heads should already have threaded stud bosses however, the bottleneck studs with no guide-plates are not for using roller rockers.
Machining the stud bosses lower .230" along with making the hole threads a bit deeper and using guide-plates will be necessary for using roller rockers; hardened pushrods are necessary when using the guide-plates.
Straight shank rocker studs like those on a Big Block Chevrolet would be necessary.
Machining the stud bosses lower .230" along with making the hole threads a bit deeper and using guide-plates will be necessary for using roller rockers; hardened pushrods are necessary when using the guide-plates.
Straight shank rocker studs like those on a Big Block Chevrolet would be necessary.
Re: Valve tip wear after cam and springs upgrade
I have always used FelPro.
The pressure reduction hypothesis does not flow in my brain very well. It will affect the pushrod geometry a small amount in theory, if you had an adjustable valvetrain. When the lifter preload is set by fully bolting the rocker to the stop, it will be less, with a shorter valve tip. If the valve tips got too short, you would have to get longer pushrods to get any lifter preload, with your non adjustable set up.
I see no point to roller rockers on your deal. Those older engines with rail rockers have been rebuilt for years with mild cams and provides millions of trouble free miles.
The hardened exhaust valve seats for unleaded gas is the biggest needed upgrade in my book.
Just out of curiosity what brand and size carburetor did you go with?
The pressure reduction hypothesis does not flow in my brain very well. It will affect the pushrod geometry a small amount in theory, if you had an adjustable valvetrain. When the lifter preload is set by fully bolting the rocker to the stop, it will be less, with a shorter valve tip. If the valve tips got too short, you would have to get longer pushrods to get any lifter preload, with your non adjustable set up.
I see no point to roller rockers on your deal. Those older engines with rail rockers have been rebuilt for years with mild cams and provides millions of trouble free miles.
The hardened exhaust valve seats for unleaded gas is the biggest needed upgrade in my book.
Just out of curiosity what brand and size carburetor did you go with?
supervel45- Posts : 4502
Join date : 2013-09-04
Re: Valve tip wear after cam and springs upgrade
As I'm not a native speaker, some terminology is new for me.rmcomprandy wrote:C9VE heads should already have threaded stud bosses however, the bottleneck studs with no guide-plates are not for using roller rockers.
Machining the stud bosses lower .230" along with making the hole threads a bit deeper and using guide-plates will be necessary for using roller rockers; hardened pushrods are necessary when using the guide-plates.
Straight shank rocker studs like those on a Big Block Chevrolet would be necessary.
Is this the stud boss, which has to be shortened by .230"?
How much is "a bit" deeper?
Okay, I do also always choose FelPro.supervel45 wrote:I have always used FelPro.
The pressure reduction hypothesis does not flow in my brain very well. It will affect the pushrod geometry a small amount in theory, if you had an adjustable valvetrain. When the lifter preload is set by fully bolting the rocker to the stop, it will be less, with a shorter valve tip. If the valve tips got too short, you would have to get longer pushrods to get any lifter preload, with your non adjustable set up.
I see no point to roller rockers on your deal. Those older engines with rail rockers have been rebuilt for years with mild cams and provides millions of trouble free miles.
The hardened exhaust valve seats for unleaded gas is the biggest needed upgrade in my book.
Just out of curiosity what brand and size carburetor did you go with?
It doesn't have to flow in your brain well. As I said, it made no sense.
I have a 650cfm AVS2 on it.
Should new valves be oversize or not necessary? Just buy new stock size, install them and go?
To answer a previous question...
The rails look fine.
There was just some wear on the side of a few rails. Probably as a result of some valve tips not being even anymore.
OlDirty- Posts : 8
Join date : 2023-06-15
Re: Valve tip wear after cam and springs upgrade
I was trying to be nice on the pressure bit, in case I misunderstood something through the translation.
I would stick with a stock size valve. All the angles need to be correct, then a light lapping.
When you or your machinist order valves, especially since you say he is new to them, I would double/triple check the part numbers, especially if ordering across the Pond and maybe with a language barrier. Ford had quite a few different valves for the 385 Sieres engines from 1968 to 1973 and later. The link below is an example of the many valves for them that are available. The 429 passenger car and later 429 medium truck engine, as well as the 429 Boss/PI/CJ/SCJ would seem a possible slip up for someone new to them.
http://sivalves.com/pdfs/2016-SI-Catalog.pdf
Your first pictures of the rocker arms looked to have wear marks on the bottom edge of the rail. It could have been the end upward angle of the rocker rail causing a photo illusion? You don't want the bottom of the rail making any contact with the valve lock or the retainer.
I would stick with a stock size valve. All the angles need to be correct, then a light lapping.
When you or your machinist order valves, especially since you say he is new to them, I would double/triple check the part numbers, especially if ordering across the Pond and maybe with a language barrier. Ford had quite a few different valves for the 385 Sieres engines from 1968 to 1973 and later. The link below is an example of the many valves for them that are available. The 429 passenger car and later 429 medium truck engine, as well as the 429 Boss/PI/CJ/SCJ would seem a possible slip up for someone new to them.
http://sivalves.com/pdfs/2016-SI-Catalog.pdf
Your first pictures of the rocker arms looked to have wear marks on the bottom edge of the rail. It could have been the end upward angle of the rocker rail causing a photo illusion? You don't want the bottom of the rail making any contact with the valve lock or the retainer.
supervel45- Posts : 4502
Join date : 2013-09-04
Re: Valve tip wear after cam and springs upgrade
[quote="OlDirty"]
Is this the stud boss, which has to be shortened by .230"?
How much is "a bit" deeper?
Yes, those are the stands which need to be machined; (and tapped a bit deeper means "whatever it takes" to accept the studs bottom threads).
It appears that is a Chevrolet head where someone has already replaced the "pressed" studs with straight threaded studs which have no hex.
That hex is needed on studs to hold any guide-plates in place.
New stock replacement exhaust valves with hardened tips are OK.
As I'm not a native speaker, some terminology is new for me.rmcomprandy wrote:C9VE heads should already have threaded stud bosses however, the bottleneck studs with no guide-plates are not for using roller rockers.
Machining the stud bosses lower .230" along with making the hole threads a bit deeper and using guide-plates will be necessary for using roller rockers; hardened pushrods are necessary when using the guide-plates.
Straight shank rocker studs like those on a Big Block Chevrolet would be necessary.
Is this the stud boss, which has to be shortened by .230"?
How much is "a bit" deeper?
supervel45 wrote:I have always used FelPro.
The pressure reduction hypothesis does not flow in my brain very well. It will affect the pushrod geometry a small amount in theory, if you had an adjustable valvetrain. When the lifter preload is set by fully bolting the rocker to the stop, it will be less, with a shorter valve tip. If the valve tips got too short, you would have to get longer pushrods to get any lifter preload, with your non adjustable set up.
The hardened exhaust valve seats for unleaded gas is the biggest needed upgrade in my book.
Yes, those are the stands which need to be machined; (and tapped a bit deeper means "whatever it takes" to accept the studs bottom threads).
It appears that is a Chevrolet head where someone has already replaced the "pressed" studs with straight threaded studs which have no hex.
That hex is needed on studs to hold any guide-plates in place.
New stock replacement exhaust valves with hardened tips are OK.
Re: Valve tip wear after cam and springs upgrade
That is the stud boss. It looks cracked in the photo. Or maybe kust a hair or glare from the light?? It is my opinion you dont really “need” roller rockers. For a stockish street motor the factory size valves will do just fine if you install the hardened valve seats to manage the modern unleaded fuel as others have already suggested. In america we call this a valve job. You dont need to over complicate things.
stanger68- Posts : 502
Join date : 2015-12-05
Location : Birmingham, Al
Re: Valve tip wear after cam and springs upgrade
I don't know what the machining cost are like over there but, if they are like here and very high now, and you don't drive your classic everyday, this "may" be something worth looking into before installing hardened exhaust valve seats. It may be good for non roller cams also. Hardened seats are still the best approach in my opinion though. Just a thought.
https://advancedenginetech.com/blog/2023/03/29/modern-additives-classic-cars/
^ It is supposed to be local also.
https://advancedenginetech.com/blog/2023/03/29/modern-additives-classic-cars/
^ It is supposed to be local also.
supervel45- Posts : 4502
Join date : 2013-09-04
Re: Valve tip wear after cam and springs upgrade
The stud boss image was from the internet as I didn't have my cylinder head around.
So to sum things up. 3 options:
1. Rocker upgrade
2. New valves - upgrade
3. Option 1 + Option 2
Regarding option 2... Why is it so hard to get stock size valves with a 1.654 head? Higher quality aftermarket ones are always larger. I can only find some stock size on Rockauto. They're basic quality though. I was trying to possibly find some in better quality.
I will ask about costs for hardened seats. But I think he said it's not worth it due to machining costs and because of the fact that I just put 1-2k mls on it per year.
So to sum things up. 3 options:
1. Rocker upgrade
- "shorten" stud bosses by .230"
- deepen thread holes of stud bosses
- get guide plates
- get hardened pushrods stock length
- get BB chevy rocker studs with hex nut (Which length?)
- get roller rockers
2. New valves - upgrade
- get new stock size valves with hardened tip
3. Option 1 + Option 2
Regarding option 2... Why is it so hard to get stock size valves with a 1.654 head? Higher quality aftermarket ones are always larger. I can only find some stock size on Rockauto. They're basic quality though. I was trying to possibly find some in better quality.
I will ask about costs for hardened seats. But I think he said it's not worth it due to machining costs and because of the fact that I just put 1-2k mls on it per year.
OlDirty- Posts : 8
Join date : 2023-06-15
Re: Valve tip wear after cam and springs upgrade
Did you try SI Valves in my above link and see if they will ship to you?
What is the desired goal/advantage of converting to roller rockers with a hydraulic camshaft?
Randy also listed several large company's above that should have the valves your after in stock, did you try any of them?
PS: The other companies mentioned should have an on line PDF catalog to get part numbers to check with places like Summit ect. for availibilty. Such as below.
https://www.elginind.com/wp-content/uploads/2021/11/Elgin-ProStock-2022-Catalog.pdf
Here is another one that came up on an Elgin search for some reason. Page 6
https://enginepro.com/downloads/EPG_OEM.ValveCatalog.pdf
What is the desired goal/advantage of converting to roller rockers with a hydraulic camshaft?
Randy also listed several large company's above that should have the valves your after in stock, did you try any of them?
PS: The other companies mentioned should have an on line PDF catalog to get part numbers to check with places like Summit ect. for availibilty. Such as below.
https://www.elginind.com/wp-content/uploads/2021/11/Elgin-ProStock-2022-Catalog.pdf
Here is another one that came up on an Elgin search for some reason. Page 6
https://enginepro.com/downloads/EPG_OEM.ValveCatalog.pdf
supervel45- Posts : 4502
Join date : 2013-09-04
Re: Valve tip wear after cam and springs upgrade
Yes I did, but whenever I enter a part number in Google, I just find pages that have nothing to do with engine parts. Maybe it's the Google algorithm because I'm in Germany. I just sent an email to them.supervel45 wrote:Did you try SI Valves in my above link and see if they will ship to you?
I was looking at less wear and friction. Thus being a small logical step towards optimizing the engine step by step.supervel45 wrote:What is the desired goal/advantage of converting to roller rockers with a hydraulic camshaft?
Melling and Qualcast are available via Rockauto, but they don't offer different quality levels like it's the case for many other parts. Same for Elgin. They also just have their OEM replacement line for the 429/460.supervel45 wrote:Randy also listed several large company's above that should have the valves your after in stock, did you try any of them?
PS: The other companies mentioned should have an on line PDF catalog to get part numbers to check with places like Summit ect. for availibilty. Such as below.
https://www.elginind.com/wp-content/uploads/2021/11/Elgin-ProStock-2022-Catalog.pdf
Here is another one that came up on an Elgin search for some reason. Page 6
https://enginepro.com/downloads/EPG_OEM.ValveCatalog.pdf
OlDirty- Posts : 8
Join date : 2023-06-15
Re: Valve tip wear after cam and springs upgrade
I hate to steer you to Ebay. These may or may not be what you are after, so double check? They claim to ship your way, also.
https://www.ebay.com/itm/325072916305?hash=item4bafdb0f51:g:GrUAAOSwmfJiGlPr&amdata=enc%3AAQAIAAAA0BikbDiqttEJGDyt5WatlHQb5R8TRSMmUcInDxDKPvditN0AA9BGHmltEkwGzWK7M6DaDrJorfdOE%2BntMg03k1C%2FdyRDMI7sEPGXxTJMQBGsHpSfg%2BJrgbg1M4Xs%2BLtfjvArzJ%2BV72Z3gTfaYZAOhIjnNVFiH50LYl8xQjjI5iyupWB04TPXI647fBs2v45vZTVx%2Fmavya8k%2Fk50s61xCgq17isFS0cJm4OhyOXyWXIt31I%2BpaMNNLkZxu0nezZ8kpKbzV8lybWE%2B%2BCBNBIQEy4%3D%7Ctkp%3ABk9SR7ru74uoYg
Double check on the hardened tip.
The first valve in the below link is the only 1.65" Stainless Steel valve for you heads I could locate.
https://www.competitionproducts.com/Ford-429_460-Stainless-Racing-Valves-11_32-Stem/products/209/
^ They seem pretty rare in that size also,
https://www.ebay.com/itm/325072916305?hash=item4bafdb0f51:g:GrUAAOSwmfJiGlPr&amdata=enc%3AAQAIAAAA0BikbDiqttEJGDyt5WatlHQb5R8TRSMmUcInDxDKPvditN0AA9BGHmltEkwGzWK7M6DaDrJorfdOE%2BntMg03k1C%2FdyRDMI7sEPGXxTJMQBGsHpSfg%2BJrgbg1M4Xs%2BLtfjvArzJ%2BV72Z3gTfaYZAOhIjnNVFiH50LYl8xQjjI5iyupWB04TPXI647fBs2v45vZTVx%2Fmavya8k%2Fk50s61xCgq17isFS0cJm4OhyOXyWXIt31I%2BpaMNNLkZxu0nezZ8kpKbzV8lybWE%2B%2BCBNBIQEy4%3D%7Ctkp%3ABk9SR7ru74uoYg
Double check on the hardened tip.
The first valve in the below link is the only 1.65" Stainless Steel valve for you heads I could locate.
https://www.competitionproducts.com/Ford-429_460-Stainless-Racing-Valves-11_32-Stem/products/209/
^ They seem pretty rare in that size also,
supervel45- Posts : 4502
Join date : 2013-09-04
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