Picture of 340/360 head porting....Mistakes?

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Cudafever

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Ok here we go. I can't post Pic's in a PM so i have started a thread to show the pic's to Yellow Rose and anyone else that is interested.
You told me i should take lot of notes this is all the notes for my 340/360 head porting.
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Here is the Clay Closed Closed Chamber
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Notice that i have already tubed the pushrod tubes

failed attempts to raise the floor and make rounder/larger SSR
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The next 2 pic's are the before.(there is a factory machined flat spot at the top of the seat. picture don't show it.)
And after when i finally got it to flow past. 500 lift. (said it was .550, i was mistaken)
That green looking stuff is called Z-spar. two part epoxy that when mixed turn that color.
Those scars are for sanding/shaping it with 36 grit sandpaper.
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There you go ;)

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Woops!
That last pic was and attempted to make the above bowl area, the mcsa. Never work, didn't stop me from sanding it and and trying way to many different shapes:BangHead: :D
 
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Cudafever said:
Woops!
That last pic was and attempted to make the above bowl are, the mcsa. Never work, didn't stop me from sanding it and and trying way to many different shapes:BangHead: :D
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The stock floor is already too tall! Making it taller is only going to lose power by making the airspeed way too fast over the S/T.
 
Things I notice.


You take awesome notes. Can't emphasize that enough.

Read the thread on speedtalk I told you about. They discuss laying back the chamber. I suspect most of what you found when you filled in th chamber was where you stood up the wall on the backside of the intake.

Top cut, top cut, top cut. That has as much to do with exit loss as almost anything else. That and the angle of the seat.

Also, I agree with screws and Brian on the floor.

Keep testing. Never stop taking notes so you never have to rely on memory. Since you can't go up in test pressure go down. And flow the ports backwards. I suspect what you will find is that everything you gained in filling in the quench part of the chamber, you will gain in reverse flow. That is bad.


Exit loss, exit loss, exit loss.

Reversion, reversion, reversion.

The two go together like peanut butter and jelly.


Nice, authentic, documented work.
 
Thanks to all.
The floor was the first thing that i fill in. just because it was the largest csa. trying to make the port equil in csa. what i found was that you can shrink the csa at the floor without changing anything in flow.(low fps air flow) but when you eliminated that swoop up to the ssr you were done. flow crash and didn't come back. I layed back the ssr until i found water there two.......then filled it back in with mud.
What i was trying to do was make the csa slowly get smaller all the way to the bowl/seat area.
What i learned was the SSR will NEVER let you do that.
So i tried to shrink the upper bowl/seat area to make it the mcsa. never got any good results from that idea.
As far as air speeds go i had 480+ fps on the ssr when i muddit up like the pic".

I have never considered anything then a 45* seat, on a Pcar head. heard stories about them beating the death out of seats and needing a special spring exc. Don't know nothing about that so never tried it.
From what i have learned on the combustion chamber side of things.....can see how it might help, if the rest of the port could be set to make it happy.
Also would help keeping the air from crashing into the vertical wall going up to the head surface.
This is one of the reason i think the clay, "closed chamber" work so well. Smooth radius all the way to the head gasket surface.
And when i did that swoop in the combustion chamber around the spark plug, i think it allowed more air to travel there and keep from backing up against the wall.
Does that make sence? Some time i have a hard time typing what i'm thinking
 
skrews said:
Those heads are done sitting on the shelf. I latter did another set very similar to those. I have them on a 360 in my Duster, has run a best of 10.6 at 122.
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So if i can be nosie, what didn't you like on the first set that you did different on the 2nt set?
 
They were intended for a motor that never got built. Just for fun I milled them down to closed chamber.
head%20pics%20007_zps4pzatpxf.jpg
 
How did it affect the flow after you did that? affect high or low lift?
 
skrews said:
lost about 5 cfm through the entire curve
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And that's a damn hard 5 CFM to get back.

Again, there's more to horsepower than CFM. Even though skrews only lost 5 CFM, that chamber will be down on power on the dyno, and on the track, the car will be lazy in th gear change. The more gears, the worse it will show up.

That is pretty much what a W-5 chamber looks like. I have run as steeps 55* seats on that chamber and found power.

Cudafever, I run 50* seats on the street. In fact, my next W-2's are going to have them, with a relatively small valve and hopefully a bowl of about 92%.They don't beat in any quicker than anything else.
 
Always wanted to try 50 or 55 degree seats in those particular heads. As for the chamber being a power loser, I'd love to do some A-B testing on the dyno to verify that. I milled those heads .110 to achieve that form, the chambers measure 54cc so keeping that test apples to apples would be difficult to say the least.
 
skrews said:
Always wanted to try 50 or 55 degree seats in those particular heads. As for the chamber being a power loser, I'd love to do some A-B testing on the dyno to verify that. I milled those heads .110 to achieve that form, the chambers measure 54cc so keeping that test apples to apples would be difficult to say the least.
Click to expand...


You can fix them...but I won't post how. Cost me many hours.

What you will see with it on the dyno is peak isn't down, but under the curve is down a bunch. It makes the gear change a problem, especially with a clutch. I can't remember if the W-7 was the same chamber as the 5 but I think it was updated.

In th mid 90's, I was talking a lot to Kent Ritter. Fortunately, I took notes (not like CF...he has a sickness with notes in a good way) so I had an idea what to look at. At the time, IIRC, Ritter-Webber was the A/A automatic record holder with a 7.77 at 177. Can't remember the heads but think they started out as 7's.

The best chambers I have seen have steep convex walls. Helps shape the flow into the cylinder. And helps with exit losses. The smart dudes call it Pressure Recovery. Also, it helps with reversion. So do steeper seat angles, but I can't say I totally understand why. I have seen, but never had any 58* cutters. Have heard some talk of 60* cutters, and a pretty sharp dude in Texas hinted to me a year or so ago guys were working with 62* seats. We are talking about ports that have flow curves going straight up at 1.3 inch lift, cam lobes that are essentially square and valve train components as rigid as you can get.

Hopefully, some of that tech will trickle down. Coincidentally, I saw my first 55* seat in 1999 by accident. If it weren't for the extra cost in valve weight, I think you'd see many more people using steeper seat angles, as they are better with tulip valves. Big, long tulip valves need to be Ti.
 
skrews said:
Always wanted to try 50 or 55 degree seats in those particular heads. As for the chamber being a power loser, I'd love to do some A-B testing on the dyno to verify that. I milled those heads .110 to achieve that form, the chambers measure 54cc so keeping that test apples to apples would be difficult to say the least.
Click to expand...

I think it would kinda be apples to apples. Shave to get compression(and a bigger quench surface) but lost in some cfm.
Original open chamber set up with potential better pressure recovery but less compression.
Basically the question would be, does making compression made that way, a plus or a neg, in power.
More compression and quench may win out.............or maybe not. sure would be a cool test!
 
The valve seat profile and valve shape along with the forms1/4 inch above and below the valve seat are everything.
 
skrews said:
The valve seat profile and valve shape along with the forms1/4 inch above and below the valve seat are everything.
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Absolutely 100% fact. You can spend a boat load of time and money just sorting out that 1/2 inch. And, you can spend a boat load of time and money on that same 1/2 inch and lose your ***. Still looking for mine.
 
yellow rose said:
Absolutely 100% fact. You can spend a boat load of time and money just sorting out that 1/2 inch. And, you can spend a boat load of time and money on that same 1/2 inch and lose your ***. Still looking for mine.
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LOL:D
 
Cudafever said:
I think it would kinda be apples to apples. Shave to get compression(and a bigger quench surface) but lost in some cfm.
Original open chamber set up with potential better pressure recovery but less compression.
Basically the question would be, does making compression made that way, a plus or a neg, in power.
More compression and quench may win out.............or maybe not. sure would be a cool test!
Click to expand...


You don't have to give up quench with the OC heads. Remember, rod/stroke ratio changes the size of the chamber. It's a time thing. Higher ratios make the piston hang at TDC longer, therefore, the chamber is smaller, longer with a higher rod ratio.

The higher ratio also affects piston time at BDC which affects exhaust lobe timing. It's like kissing your cousin. Well, not really. I just been wanting to say that. Kinda like Robs $2.00 ***** on Coke. I'm wearing that damn thing out.
 
agreed BUT whether it's a long rod or not would still be a good comparison as to, is it "better quench and compression make more or less power than pressure recovery chamber!
I know it's not going to happen but it would be interesting.
 
skrews said:
^^^ This, tried it a number of times never works.
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It only works when you raise the roof... but you cant raise it enough...and so it stalls at or just over. 500
If you were to lower the floor like a speed master...you'd probably hit water.
 
As a baseline, what does a stock 2.02 head flow on your bench?

What did that big raised port flow in that configuration, and with what sized valve?

That really rounded shape to the floor at the short turn has never worked for me.

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