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mhuppertz

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Calculating everything out I realized that my quench area between the quench block on my pistons and the open chamber is .040" without head gasket. I'm looking for .035" with HG, so I have to take the block back in to zero deck it. Crap. Guess I will have to get the intake milled a little also.
I have too much work in the 213 iron heads to switch, and being iron I need all the detonation resistance I can get, so I guess it's worth it. Sucks because I though I was ready for balance and assembly.

2020-01-26_084815.jpg
 
Did you check every hole? What was the variance?
 
Did you check every hole? What was the variance?
Not yet. My rods and pistons are new aftermarket, and are very tight tolerance, but I will check front and back on both sides to make sure the deck is straight. PITA
 
Calculating everything out I realized that my quench area between the quench block on my pistons and the open chamber is .040" without head gasket. I'm looking for .035" with HG, so I have to take the block back in to zero deck it. Crap. Guess I will have to get the intake milled a little also.
I have too much work in the 213 iron heads to switch, and being iron I need all the detonation resistance I can get, so I guess it's worth it. Sucks because I though I was ready for balance and assembly.

View attachment 1715459196


You are picking the fly poop out of the pepper. There isn't a single horsepower or any detonation resistance if you can get to .050. You can just buy thinner head gaskets from Cometic. No reason to get anywhere near. 035.
 
You are picking the fly poop out of the pepper. There isn't a single horsepower or any detonation resistance if you can get to .050. You can just buy thinner head gaskets from Cometic. No reason to get anywhere near. 035.
?what?
 
If I calculate it with the .022 steel shim gaskets I have the quench will be at least .055 and that is too much for my cam.
You are picking the fly poop out of the pepper. There isn't a single horsepower or any detonation resistance if you can get to .050. You can just buy thinner head gaskets from Cometic. No reason to get anywhere near. 035.
 
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OP is correct, now is the time to cut the block. building for .035 quench is a good thing, we can debate until the cows LOL come home but the benefits exceed that of .062
 
If I calculate it with the .022 steel shim gaskets I have the quench will be at least .055 and that is too much for my cam.


I guess I'm nuts. Like I said, you won't gain a thing, unless you are worried about compression. If you doing all this to gain quench you are wasting your time.
 
You are picking the fly poop out of the pepper. There isn't a single horsepower or any detonation resistance if you can get to .050. You can just buy thinner head gaskets from Cometic. No reason to get anywhere near. 035.
Are you saying that quech does not exist?
 
I guess I'm nuts. Like I said, you won't gain a thing, unless you are worried about compression. If you doing all this to gain quench you are wasting your time.

I would refer you to any number of articles, her is the first one that came up in a Google search (below link).
My experience is that quench is everything on an N/A, pump gas engine, weather it is high compression or not. Quench and squish are extremely important on a wedge head where the spark plug is so far away from the intake valve. It's why Hemi engines can run at least a point higher static C/R on the same octane fuel. Also affects the dynamic compression ratio based on cam timing, and the cam I am going to run creates very high dynamic pressures above 3,000 RPM, so taking all the precautions I can.

Link: What Is The Ideal Quench Height? - Hot Rod Magazine - Hot Rod
 
Can’t you mill the heads enough to get it?
Or are they already milled a bunch?

Or do the quench domes just not stick out far enough to make it workable?

What will the new CR be?
 
Can’t you mill the heads enough to get it?
Or are they already milled a bunch?

Or do the quench domes just not stick out far enough to make it workable?

What will the new CR be?

It makes the most sense to zero deck the block .030" because the quench blocks just arent sticking out enough.

Haven't calculated the new CR yet. Will do that shortly.
 
It makes the most sense to zero deck the block .030" because the quench blocks just arent sticking out enough.

Haven't calculated the new CR yet. Will do that shortly.

My machinist only had to take .003 off my 66 440 block to square it and zero deck it . My 505/4.350 pistons came out dead flush even w/ the block , used a .039 cometic , 4.380 bore head gasket , guess what , I got .039 quench , !! Wouldn`t have it any other way , despite what arguments are made by those smarter than I am !!
 
My machinist only had to take .003 off my 66 440 block to square it and zero deck it . My 505/4.350 pistons came out dead flush even w/ the block , used a .039 cometic , 4.380 bore head gasket , guess what , I got .039 quench , !! Wouldn`t have it any other way , despite what arguments are made by those smarter than I am !!
That's a perfect quench number!
 
Can’t you mill the heads enough to get it?
Or are they already milled a bunch?

Or do the quench domes just not stick out far enough to make it workable?

What will the new CR be?

If I get .030" milled off the deck I will be at 10.56:1 which is decent for my very high altitude. I live at 7,000ft
 
If I get .030" milled off the deck I will be at 10.56:1 which is decent for my very high altitude. I live at 7,000ft

No being smart about this but shouldn't you cut .030 off the heads rather than the deck or is the deck way off spec?
 
No being smart about this but shouldn't you cut .030 off the heads rather than the deck or is the deck way off spec?
My instinct is to bring the pistons to zero deck height, but maybe that isn't the best way. Will think some more about it.
 
Not yet. My rods and pistons are new aftermarket, and are very tight tolerance, but I will check front and back on both sides to make sure the deck is straight. PITA
has the deck been squared, if not, there's your answer.
 
Are you saying that quech does not exist?


I'm saying if the CR is where you want it, and you are at say .050 quench, screwing around to get it down to .040 won't make a pinch of **** diffence in either detonation resistance or power. Not one bit. BTDT.

Look at a Hemi. It doesn't have quench, but they run on 32 total. Look at the small block MoPar. They run on 35 total with the piston .100 down the hole, and you have to WORK to make it rattle.

Now, look at a SBC from the same era. Double quench, needs at least 40 total to run, and will rattle the rods right out of the block. Quench won't fix that.

Chamber shape and plug location are much more critical than quench. It's Chevy think.
 
I would refer you to any number of articles, her is the first one that came up in a Google search (below link).
My experience is that quench is everything on an N/A, pump gas engine, weather it is high compression or not. Quench and squish are extremely important on a wedge head where the spark plug is so far away from the intake valve. It's why Hemi engines can run at least a point higher static C/R on the same octane fuel. Also affects the dynamic compression ratio based on cam timing, and the cam I am going to run creates very high dynamic pressures above 3,000 RPM, so taking all the precautions I can.

Link: What Is The Ideal Quench Height? - Hot Rod Magazine - Hot Rod


Stop reading magazines where the author is just repeating crap he was told.

A Hemi does NOT have quench. Does NOT.

All I'm saying is don't curdle your milk fighting for quench. Get the CR where you want it, and work on your tune up.

Also, see my above post.
 
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