Valve Drop and Piston to Valve Clearance

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Home made tools.
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furrystump said:
I have done it when I changed from a hydr to solid lifter on the motor in the car. I was ASSURED it would ABSOLUTELY fit! I have trust issues, so I installed checker springs and a dial indicator on valve tip. Rotated the crank through a cycle stopping every 5 degs when the piston started to get closer to tdc. Push down on the valve tip to see what the tightest clearance was. They were right, there was PLENTY, but I could sleep easier checking. I would not approach the min. piston to valve clearance measuring this way. NOT precision, but worth it to me if I’m not pulling a head.
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You have made my point. You used checking springs so when you put the springs on you run you’ll have even more p/v. And you still don’t know what you have for clearance, or where that clearance is.

I’ve notched pistons because guys have used the valve drop/soft spring method that didn’t need it.

If the valve is hitting the notch (and it happens a lot) you think you don’t have enough notch depth, when in reality you have more than you need but the valve is hitting the notch.

That’s why you need to know how much clearance you have and where you have or you waste time and money and compression.

I’ll say it again, VOTDC and v/p isn’t enough information. It’s classic around this place to do sloppy work and claim it’s great. And the usual suspects are all blowing their own horns.

Correctly degreeing a cam and accurately measuring p/v is basic engine assembly. If you can’t do those simple things correctly, plus measure everything else with micrometers you shouldn’t be assembling engines.
 
Absolutely agree, not the best way. Doing it that way you could have practically zero clearance from the edge of the valve to the relief. At rpm the valve stem could flex and bam! I knew my reliefs were huge compared to my valve heads and it was an in car cam change. With comparable lift numbers. Really wanted to make sure it didn’t hit the exhaust valve as the piston chased it up the bore.
 
For checking the side clearance of the valve to piston relief, take a valve of the stem spec for the guides and cut the head off to a point. Assuming the bottom end is mock assembled. Place the head on the block, with #1 piston at TDC take your “valve spike” and make a very slight “punch” mark in the top of your piston for both valves. This will be center of valve on piston face. Do this for each piston. Next measure the valve full width, and split to find the radius, then add your wanted valve lip to relief clearance and see what come up. Measure your piston using the “center punch” mark. You may be find or you may have to fly cut each valve pocket on each piston…
 
4spdragtop said:
I'm no builder but sure looks like Max1196 used his ingenuity/creativity and found a fool proof method?
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Well. It depends. "What if" the heads you're actually using are different from the valve spring seat to the valve seat? Also, there's the valve seats themselves. The heads you're actually using would have to be very close or the same on all respects in order to come up with the same or close clearances. Having said that, I think it's a purdy dang good idea.
 
I know, it's all scary stuff :)
This method is simply another tool that can be used during engine building.
A good engine builder knows how to take advantage of the tools at his disposal.
Choose your tools. Use it or don't.
Cam companies are not specing a cam solely based on how much clearance you have, they are going off flow numbers and compression etc.

Don't know what the comp is? Check it.
Not sure what your valve head side clearance to valve relief is? Check it.
Not sure what your retainer to valve guide clearance is? Check it
Worried about final P/V, yeah you guessed it..check it.
These are pretty fundamental things.

No one is saying you can't use this method during engine mock up or it's the only thing you need to do.
It's simply another measurement you can give a cam company when ordering a cam.

Think about what happens when you order a cam.
The cam company doesn't know what clearances you have, they don't have that info so they don't care, they send you a cam based on other specifications and then it's up to you to make it fit in the space you have.
Wouldn't it be nice for them to know what that space is?

I guess all the cam companies who offer this service have no idea what they are doing..:rolleyes:
 
Rat Bastid said:
I’ve notched pistons because guys have used the valve drop/soft spring method that didn’t need it.
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32 posts in , not to mention all posts in the other thread and you suddenly come out with this. Suddenly you've remembered the time you found an issue. And somehow you know what the previous engine builder had done and how they did it?
That's something I would have said in my first post on the subject. If it had actually happened.
Considering your past around here, I'd be taking this statement ( as well as some others) with a grain of salt..
 
fishmens67 said:
I've used that method for a basic check.
When you drop a valve at top dead center, you realize there's more clearance than one might think during the overlap period.
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I guess I'm an unusual suspect. :D
 
Bakerlite said:
32 posts in , not to mention all posts in the other thread and you suddenly come out with this. Suddenly you've remembered the time you found an issue. And somehow you know what the previous engine builder had done and how they did it?
That's something I would have said in my first post on the subject. If it had actually happened.
Considering your past around here, I'd be taking this statement ( as well as some others) with a grain of salt..
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I don’t have to explain **** to you. You aren’t worth it. Considering your past around here, I’d be careful what rocks you are kicking over.

And yeah, it’s happened. If you actually built anything you’d know guessing is the sure road to unscrewing ****. Don’t guess. Measure. Valve drop is just that. It’s like measuring a bore with a tape measure.

That’s go enough for you. Not for anyone else.
 
Rat Bastid said:
I don’t have to explain **** to you. You aren’t worth it. Considering your past around here, I’d be careful what rocks you are kicking over.

And yeah, it’s happened. If you actually built anything you’d know guessing is the sure road to unscrewing ****. Don’t guess. Measure. Valve drop is just that. It’s like measuring a bore with a tape measure.

That’s go enough for you. Not for anyone else.
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LOL, your just too funny...
So first you basically repeat what I've said to you about "considering your past". :rolleyes:
That's true form from you considering most of what you say is just something you've parroted from someone else or U Tube.
I'm still on my original user name around here since 2007. How many have you had? Every time you get caught with your foot in your mouth or stinking up a user name, you run off and create a new account, thinking your clever and it's going to erase that stink or your lack of credibility..It might work with the newbies around here, but not with everyone who knows you.

Then you question that I've "actually built anything" knowing full well that I do this professionally for a living and have done so for quite a while. Do you do it for a living?
All that shows is your capable of blurting out something totally nonsensical to try and bolster a flimsy argument.
And who's guessing? You seem to be the only one here who thinks no one's checking clearances.
But that's because your better than everyone else ... Right???

I try to enlighten members to what is possible, if their willing to take the time to explore it.
All you do is blow your own horn and if it didn't emanate from your keyboard then it's nothing more than total BS..
You could have added something positive to the thread and simply listed some things people would need to check if they use this method, but oh no, not you.. You'd rather get out the blow horn, ignore what people are saying and carry on like a twat..

I guess I must be the luckiest engine builder in the world to have done it successfully for so long without checking any clearances. I'm surprised NASCAR teams aren't knocking at my door. :D
 
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Didn’t Engine Masters have a really good show on this. I just can’t remember the episode.
 
Bakerlite said:
LOL, your just too funny...
So first you basically repeat what I've said to you about "considering your past". :rolleyes:
That's true form from you considering most of what you say is just something you've parroted from someone else or U Tube.
I'm still on my original user name around here since 2007. How many have you had? Every time you get caught with your foot in your mouth or stinking up a user name, you run off and create a new account, thinking your clever and it's going to erase that stink or your lack of credibility..It might work with the newbies around here, but not with everyone who knows you.

Then you question that I've "actually built anything" knowing full well that I do this professionally for a living and have done so for quite a while. Do you do it for a living?
All that shows is your capable of blurting out something totally nonsensical to try and bolster a flimsy argument.
And who's guessing? You seem to be the only one here who thinks no one's checking clearances.
But that's because your better than everyone else ... Right???

I try to enlighten members to what is possible, if their willing to take the time to explore it.
All you do is blow your own horn and if it didn't emanate from your keyboard then it's nothing more than total BS..
You could have added something positive to the thread and simply listed some things people would need to check if they use this method, but oh no, not you.. You'd rather get out the blow horn, ignore what people are saying and carry on like a twat..

I guess I must be the luckiest engine builder in the world to have done it successfully for so long without checking any clearances. I'm surprised NASCAR teams aren't knocking at my door. :D
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Correction: he doesn't run off he is thrown off! LOL. It was mad scientists till about 2014 and then notice the same month of 2014 yellow rose popped up then when yellow rose got cut out in 2020 guess who popped up... LOL
You're giving them credit for knowing when the getting is good..
Let's see how long the monitors can hold out this time...
 
j par said:
Correction: he doesn't run off he is thrown off! LOL. It was mad scientists till about 2014 and then notice the same month of 2014 yellow rose popped up then when yellow rose got cut out in 2020 guess who popped up... LOL
You're giving them credit for knowing when the getting is good..
Let's see how long the monitors can hold out this time...
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it was last year, as in 2021, not 2020 Ding Dong. You have his number, why don’t you call him and ask instead of starting a conspiracy theory.
 
Scody21 said:
it was last year, as in 2021, not 2020 Ding Dong. You have his number, why don’t you call him and ask instead of starting a conspiracy theory.
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Does it really matter what year? The point is he's been given time outs numerous times and fails to get the message.
I wouldn't consider that a conspiracy theory, I would consider that as fact.
His last post as YR was on the Jun 30, 2021
His first post as Rat was July 25, 2021 and this was an account that was created on Nov 23, 2020. Some Six months before YR was banned.
Why is he creating multiple accounts that overlap? One can only guess.
And what do you think he did then?? Yep that's right, only 4 posts in on the Rat account and he's headed straight back to the NP section, the same section that he was banned from as YR. Again, not getting the message, and thumbing his nose at the Moderators.
And what does he do when he gets there? Yep you guessed it again, starts engaging in the same harassment that got him banned in the first place. Again, not getting the message.
 
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He was banned ..RustyRatRod posted this at the time.
"Yellow Rose cannot access the site since he's been banned. "

And he's not changing an account name he's creating new accounts that overlap.
Anyway, I'm sick of talking about him..Time to move on..
Let's just let the members here decide for themselves if they find this subject worth exploring or not..
 
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If you look up one of his old names and there is a line through it he was banned from the site. We know who he is regardless what name he uses.
 
I could care less who he is, I'm a big boy.
It's hard to ruffle my feathers.
Give me any grief and I'll throw a ballpeen hammer across the shop at ya.:D :lol:
 
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