A new head design (fantasy)

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My drawers are just fine. I never said the OHC was a cure all. I said it has advantages over a push rod head. Stop making **** up. Everything has advantages and disadvantages. I don't see Ford as a leader in engineering design so what they do or don't do is of little consequence to me.
 
gzig5 said:
My drawers are just fine. I never said the OHC was a cure all. I said it has advantages over a push rod head. Stop making **** up. Everything has advantages and disadvantages. I don't see Ford as a leader in engineering design so what they do or don't do is of little consequence to me.
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Not making anything up dude. I pointed out what you think needs to be fixed doesn't need fixing. Unless you think European thinking is thinking. I don't eurothink, no matter how popular it is.
 
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Idk what the bore and stroke is like these days but when I saw bores equal to or lesser than stroke I wanted to barf lol. Leave that **** for tractors lol.
 
19DUSTER73 said:
Idk what the bore and stroke is like these days but when I saw bores equal to or lesser than stroke I wanted to barf lol. Leave that **** for tractors lol.
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That's the new "engineering". Under square engines, in an OHC configuration to make them small and use a turbo.

If you're paying attention the car manufacturers have already said where they are going and why. It's not better. It's just what they want and they want to make the government happy.

I think it was the Fiat jackass in an interview who claimed the end game was to essentially eliminate competition between the car companies, have everything made to spec chassis and power trains so there was uniformity and parts interchangeability between all manufacturers!

I almost crapped my pants. That is 100% euromarxist thinking. You won't end up with a better product, or a cheaper product. You'll end up with junk, at a higher price, without an option.

Screw Europe.
 
Right or wrong I've been in love with the big bore short stroke ideal since I figured out how an internal combustion engine operates.
 
The 4.7l was basically what an ohc Chrysler v8 would look like.

Sadly, it was a smog motor with tight bore spacing and small bores to help emissions. Neat engines, but putting the cam up high in an aluminum head is a challenge since the cam towers need strength and the head also has to be hollow for water.. So there's flex and engineering challenges to control it. The 4.7 was chain driven with three timing chains. Any conversion head would have to use a belt, or some sort of super alien looking timing cover to hold the chains inside.. Bore stagger makes this non trivial. Then there's the space used up on the front of the motor that the water pump and alternator will have to deal with.

Still, it's an architecture that can work and does flow very well, but making ohc heads for an LA motor is no easy task. Hell, you'd still need to spin a dummy cam just to drive the oil pump and distributor! That's 3x the rotating mass of a single cam..

The R/W/P style of motors showed that flow is not the limiting factor with a pushrod layout. If a small block stands any chance of making use of the higher flow of no pushrods, the changes need to start with the block not the heads.

Multi valve layouts exist for efficiency (port velocity and turbulence) It's all about reducing fuel consumption and emissions. Some efficiency is realized as extra power, but mostly the result is simply less fuel used between start and stop.. Would take mighty expensive gas to pay off a multi valve ohc head conversion setup. If built properly, the two valve version would still make the same power across the whole operating range too.

Theoretically, is still love an ohc LA based engine. Cam swaps would be a breeze and so would advance/retard changes. The ONLY reason I'd want to see a dohc is that lsa could be adjusted without new cams having to be ground. But the reality is that the cam drives would eat up space, the timing cover design required would be complex, and it's not likely to weigh less because the overall design wouldn't be optimized for an ohc layout. Plus, even a modest head would easily grenade a stock block, and there would still be a ton of inherent problems with other aspects of a stock block..
 
pittsburghracer said:
Now that we have a few more guys thinking about head flow think past the head. This may get you to understand shortside shaping. Let’s take a small block Mopar head and use it in our discussion. Where does the common wall side of an intake port dump into an engine cylinder. How about the pushrod side? Until you understand this it’s really hard to maximize head flow unless the guy teaching you showed you how. Most of us weren’t that lucky but it sure would have shortened my learning time and prevented a few sleepless nights. Like I told a few guys before I used to keep a pen and notepad by my bed at night for ideas that popped into my head while sleeping
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So the common wall dumps right on the cylinder wall and the pushrod side more in the center. I read a little about port bias (not much info in the article). Will the chamber and the cylinder wall on the common wall side act as an extension of the port to some degree? I could see the flow potentially staying cleaner on that side.

Does anyone have Vizard's How to port and flow cylinder heads? I'm gonna order it I think. Read a few excerpts. Made the book look very informative.
 
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Look like the teach, is making us work for this, i guess we can bounce ideas back and forth for now.

I like your idea about the wall being a extension of the port, Makes sence.
If you put a velocity tube against the wall(any wall) there is next to nothing for air speed, pull it just off the wall and there it is.

I think the long wall is going to be the slowest speed of the port(at the valve)
And the prp side of the ssr, and the prp wall, is were most of the air is going to travel.
At low lift i think it will be reasonably equil in flow but as it start to open.......let's say .300" lift, the more it's going to shift to the prp side of the valve. causing the mid to prp side of the ssr to have the most air speed.

Is that because the long wall side of the valve has the most shrouding? or that the prp side is more on center in the bore????
I don't know.
 
19DUSTER73 said:
So the common wall dumps right on the cylinder wall and the pushrod side more in the center. I read a little about port bias (not much info in the article). Will the chamber and the cylinder wall on the common wall side act as an extension of the port to some degree? I could see the flow potentially staying cleaner on that side.

Does anyone have Vizard's How to port and flow cylinder heads? I'm gonna order it I think. Read a few excerpts. Made the book look very informative.
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Now you are thinking. I have his book and several others I bought off amazon but never read. I will drag them out when I get s chance and give you the titles. One is a Chevy book and very good. Keep thinking about the shape and why it can’t just be shaped like a dam on a river.
 
This is cool. I like they way this is going. I have to get back to work though lol
 
Vizard's book is very good read. I really enjoyed it. The information will seam either basic or advanced, depending on how much you pay attention.
Another good one from a different author is called, if I recall correctly, Practical Engine Airflow.
 
I would like to see a new head based around the poly design. Canted valves, the spread port gets rid of the hot spot with the two center exhaust ports are and can be designed where the intake ports are more if a straight shot to the valves. Give it a modern chamber and I think it would make very good power.

The sad part is hardly no one would buy them. It would be the same old excuses. It can't use my stock rockers, intake or exhaust. Or my favorite, it doesn't look like my factory heads.
 
Bobzilla said:
Vizard's book is very good read. I really enjoyed it. The information will seam either basic or advanced, depending on how much you pay attention.
Another good one from a different author is called, if I recall correctly, Practical Engine Airflow.
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I need to go dig that one up. bought that book when i tried to build a flow bench out of a vacuum and a hollow spark plug(Long story :BangHead:)
Edit! found it. it called
PRACTICAL GAS FLOW
BY JOHN DALTON
I think i need to re read this one.
 
A block as big as a"big block" with only 318 cubic inches. had no interest in that.................now i wish i would have taken the opportunity to crack open a few of them..................
 

I haven’t been following this post real close as some of those heads and engines I would never run but keep in mind making any port bigger than necessary leads to a lazy port. I big port makes a lazy engine (think 426 Hemi). To overcome this mods will be needed and rpm adjusted accordingly.
 
Cudafever said:
My experimental factory iron head has found the water on the ssr the water in the bowl. hell i have even found oil :rofl:
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Must have went into the rocker oil feed, tube it. Ive blown the roof on 225 heads, guide is paper thin on one side. Ive blow through the low sitting head bolt, hard washer and jb weld fixes that.
I dont lay turn back enough to hit water. but if or when i do.., kinda like doing glue down carpet job.. its not i its gonna happen ..its when... you get glue all over your hand or arm or shirt , tools..itll be the straight side bowl im sure...
 
pittsburghracer said:
I haven’t been following this post real close as some of those heads and engines I would never run but keep in mind making any port bigger than necessary leads to a lazy port. I big port makes a lazy engine (think 426 Hemi). To overcome this mods will be needed and rpm adjusted accordingly.
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Which is about impossible with a prod head, but probable with a 190cnc on a 340 with your 'average person' 'too big for gears' cam.
I think 180-185 cc is bitchin for dual purpose motors.. IF its working right
 
MOPAROFFICIAL said:
Must have went into the rocker oil feed, tube it. Ive blown the roof on 225 heads, guide is paper thin on one side. Ive blow through the low sitting head bolt, hard washer and jb weld fixes that.
I don't lay turn back enough to hit water. but if or when i do.., kinda like doing glue down carpet job.. its not i its gonna happen ..its when... you get glue all over your hand or arm or shirt , tools..itll be the straight side bowl im sure...
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Nah i found oil when i ground way too much, just past the prp area, and ground into the valve cover/rocker arm/pushrod area.
Slapped some mud on it and moved on. This area was were i got crazy and in the end had minus numbers on my Velocity Probe, in that area.
O yah, and lost 20 cfm of flow.........Don't know were it when..........:BangHead:
 
Cudafever said:
Nah i found oil when i ground way too much, just past the prp area, and ground into the valve cover/rocker arm/pushrod area.
Slapped some mud on it and moved on. This area was were i got crazy and in the end had - numbers on my probe, in that area.
O yah, and lost 20 cfm of flow.........Don't know were it when..........:BangHead:
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At the top n bottom .it dips down and in before the pushrod hole on the outside ..lol.. i saw that and was like thank God i didnt push harder there...easy to miss that and go through.
I started to go through the pushrod pinch on my J heads . It got dark colored and i pulled back... pick poked right through, balzoa time...but now i think im going to tube them
 
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Yup! When the pitch of the grinder bur changes.........You know you have gone to far, before you ever go threw.
 
Cudafever said:
I need to go dig that one up. bought that book when i tried to build a flow bench out of a vacuum and a hollow spark plug(Long story :BangHead:)
Edit! found it. it called
PRACTICAL GAS FLOW
BY JOHN DALTON
I think i need to re read this one.
Click to expand...
I am not familiar with that one but perhaps I'll look into that one too.
John Baechtel is the author of the one I was referring to; Practical Engine Airflow. It's a good read as well.
 
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