Ford 400 Compression
Hotshot
Joined: Jul 2020
Posts: 10,268
Likes: 2,563
From: Near Salt Lake City
Did you not read the definition of quench being "the distance between the piston and the cylinder head combustion chamber"?
EVERY engine / piston / combustion chamber has quench
You are arguing with a master
EVERY engine / piston / combustion chamber has quench
You are arguing with a master
Lead Driver
Joined: Nov 2000
Posts: 6,619
Likes: 340
From: Albuquerque
I know what all of those heads look like and have owned them. A head needs a flat area to provide quench and a piston to match. Otherrwise you don't get any squish into the reduced area. You don't appear to be a master too me.a little too full of yourself.
Lead Driver
Joined: Nov 2000
Posts: 6,619
Likes: 340
From: Albuquerque
For those intereested in the definition of "quench" and what it means this is good. Open chamber head cannot apply quench unless youv'e got some king of popup pistons.
https://www.enginelabs.com/engine-te...ston-and-head/
https://www.enginelabs.com/engine-te...ston-and-head/
Hotshot
Joined: Jul 2020
Posts: 10,268
Likes: 2,563
From: Near Salt Lake City
You appear to be part moron
I got my Ford masters cert in 1998 and have been doing this all my life
Logistics Pro
Joined: May 2015
Posts: 4,461
Likes: 950
From: Tri Cities, TN
Now that we have totally hijacked the man's thread.
A paragraph from an article by George Pence a man who spent his life working on Clevelands. COBRA JET: Unleashing The Performance Capabilities Of 351 Cleveland Engines With Open Chamber 4V Heads (Q Code) | The De Tomaso Forums
The broad and shallow Cleveland chambers, resulting from the low valve angles, are superior to wedge chambers. Open chamber versions of the Cleveland head obviously have no quench areas to shield any portion of the combustion chamber from the flame front. There isn't enough quench area to make a detrimental impact upon horsepower in the quench chamber versions of the Cleveland cylinder head either; no part of the combustion area is significantly hidden from the flame front, minimizing quench clearance is not needed to expose otherwise unburned air/fuel mixture. The Cleveland cylinder head creates turbulence within the combustion chamber by virtue of the chamber's shallowness. I know from experience the open chamber heads resist detonation equally as well as the quench chamber heads, both versions can operate at the same compression ratios.
A paragraph from an article by George Pence a man who spent his life working on Clevelands. COBRA JET: Unleashing The Performance Capabilities Of 351 Cleveland Engines With Open Chamber 4V Heads (Q Code) | The De Tomaso Forums
The broad and shallow Cleveland chambers, resulting from the low valve angles, are superior to wedge chambers. Open chamber versions of the Cleveland head obviously have no quench areas to shield any portion of the combustion chamber from the flame front. There isn't enough quench area to make a detrimental impact upon horsepower in the quench chamber versions of the Cleveland cylinder head either; no part of the combustion area is significantly hidden from the flame front, minimizing quench clearance is not needed to expose otherwise unburned air/fuel mixture. The Cleveland cylinder head creates turbulence within the combustion chamber by virtue of the chamber's shallowness. I know from experience the open chamber heads resist detonation equally as well as the quench chamber heads, both versions can operate at the same compression ratios.
Cargo Master
Joined: Oct 2020
Posts: 2,631
Likes: 761
Open chamber heads still have a quench area (defined as piston to head area)
Zero deck height is a doable thing for a racing engine
Big problems in a street motor IMO with piston to valve clearance
Not so much of a problem with a Ford 400, and those motors sure do benefit with more compression
Ran stock steel shim head gaskets in my '69 302 Chev forever (came stock with steel shim head gaskets)
Sucked a few valves over the years (broken valve springs) mostly
Should have took a picture of the sucked valve in my 69 Z-28 when I put 2.05 turbo angle plug fuelie heads on it
Live and learn
Zero deck height is a doable thing for a racing engine
Big problems in a street motor IMO with piston to valve clearance
Not so much of a problem with a Ford 400, and those motors sure do benefit with more compression
Ran stock steel shim head gaskets in my '69 302 Chev forever (came stock with steel shim head gaskets)
Sucked a few valves over the years (broken valve springs) mostly
Should have took a picture of the sucked valve in my 69 Z-28 when I put 2.05 turbo angle plug fuelie heads on it
Live and learn
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Hotshot
Joined: Jul 2020
Posts: 10,268
Likes: 2,563
From: Near Salt Lake City
My first recall job for a Ford dealer was a gas tank shield on a Pinto
That was in '79
I was happy to do that job
Nobody else wanted to
They had already done thousands
I taught young apprentices of mine to add fuel line one way valves and I got the time on my flag sheet
That's the other way to make 20 hours a day as a tech
That was in '79
I was happy to do that job
Nobody else wanted to
They had already done thousands
I taught young apprentices of mine to add fuel line one way valves and I got the time on my flag sheet
That's the other way to make 20 hours a day as a tech
Logistics Pro
Joined: May 2015
Posts: 4,461
Likes: 950
From: Tri Cities, TN
I went back and re-read all of your posts in this thread none were helpful to the thread starter, and some were downright inaccurate. We don't care what you did for a living. If you are trying to prove something to us, it ain't working.
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