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Kinda wounder about high swirl cylinder heads as Ford and Chevy found too much swirl and not enough tumble leads to rapid cylinder wall and ring wear.
 

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Swirl aims the intake charge toward / around the cylinder wall, washing the wall down with fuel. Tumble aims the intake charge hitting the top of the piston which churns the charge in a more violent motion. More like an explosion instead of like flushing a toilet.
Depending on combution chamber design valve angles port shape enhances as to how much tumble vs swirl is produced.
Engine like a certian amount of both. Chevy in the past had a bit more swirl than Ford. At one point the early Vortec heads and early Modular Ford engines were designed with high swirl buth had excessive cylinder wall and ring wear. Saw evidence of this in tear down displays in Fords tear down room. Also had a friend the had a engine reman business that was seeing evedence of excessive wear in the swirl port engines.

Ford went almost 100% swirl after that Chevy stepped back to more of a combo in the newer Vortec heads.
On a side note most diesel 4 valve engines one intake valve in connected to a purely (as possible) tumble port the other a dedicated swirl port. Very important as a diesel as there is no plug to fire the mixture.

At one point in a somke break room discussing this with an engineer that was responcible for tear down inspections. I told him he could tell the valve configuration by cylinder wall wear 2 valve ,3 valve, 4 valve. Explaned the patterns our Ford heads made. He thought about it a minite all of a sudden his face lit up and said your right.
 

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Discussion Starter #10
Swirl aims the intake charge toward / around the cylinder wall, washing the wall down with fuel. Tumble aims the intake charge hitting the top of the piston which churns the charge in a more violent motion. More like an explosion instead of like flushing a toilet.
Depending on combution chamber design valve angles port shape enhances as to how much tumble vs swirl is produced.
Engine like a certian amount of both. Chevy in the past had a bit more swirl than Ford. At one point the early Vortec heads and early Modular Ford engines were designed with high swirl buth had excessive cylinder wall and ring wear. Saw evidence of this in tear down displays in Fords tear down room. Also had a friend the had a engine reman business that was seeing evedence of excessive wear in the swirl port engines.

Ford went almost 100% swirl after that Chevy stepped back to more of a combo in the newer Vortec heads.
On a side note most diesel 4 valve engines one intake valve in connected to a purely (as possible) tumble port the other a dedicated swirl port. Very important as a diesel as there is no plug to fire the mixture.


the valve configuration by cylinder wall wear 2 valve ,3 valve, 4 valve. Explaned the patterns our Ford heads made. He thought about it a minite all of a sudden his face lit up and said your right.
WOW!!! lots of good info right there. esp on the diesel as I am a ford diesel tech. but all the ford hot rods get my goober. ive wondered why ford had changed port designs so much in the modular family. and in the chambers. I wasn't aware that this would cause cyl wear be it upper or lower or abnormal. in boosted form does it make a difference? further more can you see a difference in the the port design with the naked eye...? could the cyl wear issue be one of the reasons for the compact graphite blocks...? as I hear the are hard as hell to machine..?
thanks for the info turbo that's good stuff.
 

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I ws the design engineer involved with the first design of of a compacted graphite block. Came up with about 38 some improvements over the 6 or 7 Modular block designs in production at that time. Many changes would have helped any block. Some of the changes the enginees couldnt understand what I WANTED to do and why. Frieds art fORD HAVE TOLD ME SOME OF MY CHANGES ARE BEING understood. The block was never cast and looking at a few pics of the CG blocks I have seen offered from FRPP dont see any of the outside mods for strength or water jacket cores. They probably lost my design in upgrades of CAD lots of models drawings were never up dated.
We did a lot of testing involving machining of CG. Do to its strength wall thicness could be reduced saving a lot of weight. Done right possibly lighter than aluminum with enough research, testing and still be stronger.
Machining testing with the hardness desired proved to be much easier than regular cast iron. It ment a cost savings in tooling as the tooling / cutters, drills etc would not have to be changed as often and it was an almost unbelieveable differance.
The issue was the process used to make CG. If the process goes wrong you end up with material thats as soft as butter or material thats as hard as the hardest cast steel known. So it could end up too weak or so hard it would be almost impossable to machine.
To make it worse at the time I believe there were 3 process to cast it (not positive abut # of process its been 20 some years ago). 2 of the processes were difficult to acheeve proper hardness desired. The 3rd one withthe best resulting results had a patten on it and the guy wanted 75.00 for each part produced using it. FORD WOULNT buy into THAT in any production engine
 
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