Valve truble

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i think it looks like the Exh valves are higher.

so with quality work, how much variance between valve tip heights is acceptable?
 
i think it looks like the Exh valves are higher.

so with quality work, how much variance between valve tip heights is acceptable?

When refurbishing well used heads(which can have substantially differing levels of seat wear/recession from hole to hole), this question usually becomes........ how much are you willing to spend to have things like tip heights be “really” close?
Especially if over sized valves aren’t part of the plan.

I’ve seen many rebuilt heads that came from large volume rebuilders where they just install new seats in every hole.
That’s great for restoring the tip heights to the OE spec, but often is done in a manner that isn’t conducive to good airflow.
 
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When refurbishing well used heads(which can have substantially differing levels of seat wear/recession from hole to hole), this question usually becomes........ how much are you willing to spend to have things like tip heights be “really” close?
Especially if over sized valves aren’t part of the plan.

I’ve seen many rebuilt heads that came from large volume rebuilders where they just install new seats in every hole.
That’s great for restoring the tip heights to the OE spec, but often is done in a manner that isn’t conducive to good airflow.
I agree whid you the question is can i cut the tip to get all the valves in the right hight
 
I agree whid you the question is can i cut the tip to get all the valves in the right hight
Have anymore pics of the heads?
Seat depths, valve lengths...all factors.
What casting?
Can you lay a ruler across the valve tips and take a pic, close up?
Strange a shorter valve would take a rotator too when there about ziltcho room left for bind..but hey.. I'm not a walking parts catalog.
 
Stem heights are critical, adjustable rockers or not. To say adjustable rockers are more forgiving is just plain wrong. Throw the rockers in the ditch and leave them out of the equation. Valve stem heights should be as equal as possible. On the slant 6 head I had done last year, there is no more than a .002" variance.
 
How mutch diferens between the tips is axeptebol

All the valve tips should be at the same height. Lay a straight edge across them so you get them all in line. Sometimes You have to grind the tip if someone cut the valve seat a little deep.

I like what @318willrun is saying to use non rotator retainer valves. The valve tips will be closer to the proper height for you.
 
Ok iv mesured and cut the tips even across the head now in shim the sprins to the right hight just for info the tips are harden right trowe the hole stem
 
Strange a shorter valve would take a rotator too when there about ziltcho room left for bind..but hey.. I'm not a walking parts catalog.

I would have thought with your vast SBM knowledge that you’d know the applications that use exhaust rotators also use shorter springs with them.

If you don’t think the info I posted about the valve lengths is accurate........ look it up yourself.

The main reason you wouldn’t normally use the HD valves in a HP application is because even when you eliminate the rotator, the stock retainer will have less installed height than if a std 4 groove valve is used...... as seen with the tip height disparity in the OP’s pic.
The .011” OAL difference is negligible.
 
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I would have thought with your vast SBM knowledge that you’d know the applications that use exhaust rotators also use shorter springs with them.

If you don’t think the info I posted about the valve lengths is accurate........ look it up yourself.

The main reason you wouldn’t normally use the HD valves in a HP application is because even when you eliminate the rotator, the stock retainer will have less installed height than if a std 4 groove valve is used...... as seen with the tip height disparity in the OP’s pic.
The .011” OAL difference is negligible.
Ok now all the valves has the same hight from spring pocket to the tip iv mesured the distance from spring pocket to the underside of the retainer and all mes are lover than the recomended spring hight of 1.69" so next on the agenda is to cut the spring pockets down to the right hight
 
I would have thought with your vast SBM knowledge that you’d know the applications that use exhaust rotators also use shorter springs with them.

If you don’t think the info I posted about the valve lengths is accurate........ look it up yourself.

The main reason you wouldn’t normally use the HD valves in a HP application is because even when you eliminate the rotator, the stock retainer will have less installed height than if a std 4 groove valve is used...... as seen with the tip height disparity in the OP’s pic.
The .011” OAL difference is negligible.
I didnt expect all kinds of butthurt in your response after sharing a typed thought. Let me know if I'm your competitor or something..I'll go somewhere else where we all work together and leave you to your mountaintop of delicate ego.
Like i said... I'm no parts catalog and I dont use stock parts in my heads..all of it is worn out, stems, face toast..



If this is how its going to be now ..you can have it.
 
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so next on the agenda is to cut the spring pockets down to the right hight

Sounds like you’ve got a handle on the situation
:thumbsup:

I wouldn’t go nuts with how deep you cut them.
Probably about .050” max.
 
Classic 360 head disaster waiting to happen!

Rotator retainers changed out for stock ones...
The rotator exhaust valve has a unique 'baby spring' from a toy engine...
When you replace it with a stock spring it gets bound on full lift.
This snaps the collet area off the top of the valve and fires it into the piston.

Last 360 I bought had been modified in this way with a bigger cam and smashed the valve straight through the piston top!

The hit was so hard it lifted the head and cracked the block around the bolt hole fixing.

Total BUTTHURT for the 360 engine owner.

Then my BUTTHURT was buying the engine expecting to be able to fix it...

Lets all calm down and have a BETTER 2022 without all this BUTTHURT...
 
Classic 360 head disaster waiting to happen!

Rotator retainers changed out for stock ones...
The rotator exhaust valve has a unique 'baby spring' form a toy engine...

Last 360 I bought had been modified in this way with a bigger cam and smashed the valve straight through the piston!
???? Now im lost my ex valves is from a earley 70s 360 thay are not rotator valves
 
I didnt expect all kinds of butthurt in your response after sharing a typed thought.

Riiiiiiighht.
No negative connotations in your remarks.
Just sharing a thought.

So, you never use OE parts in your heads, but didn’t seem to have a problem implying the info I posted about them was incorrect?
 
Hi Plymouth37,

Yes you bought the wrong valves...

360 Exhaust valves are not the same as 340 ones!

They are designed for the 'rotator retainer' for truck engines.

The spring is shorter ''360 heads'' and they cannot be retro fitted for the stock 340/318 springs.
 
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Thread started in garage tools etc.

YES you can get TWO groove 360 exhaust valves!

Aftermarket ones, I have some here too.

The large stem 'sticking OUT' at the top is the 'give away'

360 ex valves height.jpg


If you run any more than a stock cam the retainer will hit the valve seal and DISASTER!!!
 
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Remove the spring and check the valve travel.

I bet with the seal fitted its less than 0.400 total before the retainer 'crushes' the seal...

Old school umbrella seals are pretty useless.

I always fit positive stem seals now.

Roo guide work.jpg


Roo poly head work.jpg
 
There is no question about whether or not one can get 2 or 4 groove exhaust valves.
My comment was, I have never seen a set of two groove exhaust valves in a set of factory assembled heads that didn’t have rotators with them.

Maybe some came that way, but I have never come across that.

Nonetheless, if the OP has the tip heights evened out, spring heights correct, and adequate retainer to seal clearance........ it doesn’t matter if he got there with 2 or 4 groove valves.
 
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Most folks are unaware of the limited valve travel in small block heads!

Some just remove the seals like old hemi heads and ''suffer the smoke''

It happens more often than folks want to admit too.

As we always say, ''CHECK AND DOUBLE CHECK'' when modifying heads!!!

Even if you get away with a BIGGER camshaft the retainer hitting the seals will act like an OILPUMP!!!

Oil consumption will go through the roof lol...
 
Most folks are unaware of the limited valve travel in small block heads!

Some just remove the seals like old hemi heads and ''suffer the smoke''

It happens more often than folks want to admit too.

As we always say, ''CHECK AND DOUBLE CHECK'' when modifying heads!!!

Even if you get away with a BIGGER camshaft the retainer hitting the seals will act like an OILPUMP!!!
Ok thanks for the input om gona check all that when i have the cam in place
Oil consumption will go through the roof lol...
 
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