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Re: New SBC Manifold with tooling
Posted: Thu Jun 06, 2019 5:32 pm
by PRH
I wonder if there is enough DOD type work available to keep every cnc porting type machine that’s currently in use porting heads busy making all that extra money.
Or would you end up with a surplus of shops equipped to do the work, which I’m guessing most of the time is put out for bid, so then the shops with the underutilized machines would start bidding lower to keep their machines busy.
Re: New SBC Manifold with tooling
Posted: Thu Jun 06, 2019 5:49 pm
by JoePorting
Seems like every CNC shop I went to was busy with DOD work in the Los Angeles area. They seemed to have 6 months to 2 years worth of work. When they found out I was a "Hotrod guy" looking to do a few heads, they lost interest really fast. They're only interested in the million dollar govt contracts.
On the flip side, when military spending gets cut, lots of these shops will be out of business. That's the nature of the aero-space industry in the Los Angeles area. Feast or famine.
Re: New SBC Manifold with tooling
Posted: Thu Jun 06, 2019 7:03 pm
by Kevin Johnson
JoePorting wrote: ↑Thu Jun 06, 2019 5:49 pm
Seems like every CNC shop I went to was busy with DOD work in the Los Angeles area. They seemed to have 6 months to 2 years worth of work. When they found out I was a "Hotrod guy" looking to do a few heads, they lost interest really fast. They're only interested in the million dollar govt contracts.
On the flip side, when military spending gets cut, lots of these shops will be out of business. That's the nature of the aero-space industry in the Los Angeles area. Feast or famine.
Aside:
When I had my Jags I visited a gentleman in SoCal at his home which had Jag heads and blocks stacked from floor to ceiling on every wall of his garage (hundreds?). He mentioned that he had many more at his shop. He told me that he had DOD contract work for milling Titanium for the Navy (kept in a safe). He sure knew a lot about Jag castings.
I remember thinking that I would need to get out of that garage quickly during an earthquake. That was just before the Northridge Quake in 1994.
Re: New SBC Manifold with tooling
Posted: Thu Jun 06, 2019 7:14 pm
by SchmidtMotorWorks
JoePorting wrote: ↑Thu Jun 06, 2019 5:49 pm
Seems like every CNC shop I went to was busy with DOD work in the Los Angeles area. They seemed to have 6 months to 2 years worth of work. When they found out I was a "Hotrod guy" looking to do a few heads, they lost interest really fast. They're only interested in the million dollar govt contracts.
On the flip side, when military spending gets cut, lots of these shops will be out of business. That's the nature of the aero-space industry in the Los Angeles area. Feast or famine.
You have it exactly right.
If an aerospace 5 axis shop had to work for automotive rates, they would generally prefer to go out of business.
The investment is too big, the reward too small and the market is in decline.
I you are going to do something for fun might as well do something really fun. The manufacturing side of making heads is not fun at all.
Re: New SBC Manifold with tooling
Posted: Thu Jun 06, 2019 7:17 pm
by SchmidtMotorWorks
PRH wrote: ↑Thu Jun 06, 2019 5:32 pm
I wonder if there is enough DOD type work available to keep every cnc porting type machine that’s currently in use porting heads busy making all that extra money.
Or would you end up with a surplus of shops equipped to do the work, which I’m guessing most of the time is put out for bid, so then the shops with the underutilized machines would start bidding lower to keep their machines busy.
I don't know but I guess there are 100 guys doing aerospace work for every guy doing cnc head porting.
A lot of people (myself included) sometimes make the mistake of thinking that if something is difficult, that it is valuable. And then make the mistake of investing time and money in it.
Re: New SBC Manifold with tooling
Posted: Tue Jun 18, 2019 3:52 pm
by JoePorting
Exhaust Port.jpg
Thought I would show what my exhaust port profile looks like. It's a full 5 inches off the deck, so I don't think there's a V8 exhaust port like it. What I found interesting this weekend was that as I was watching a "Titan Visits Roush Yates Engines" youtube video, on 1:42 an exhaust port just like mine shows how the exhaust gases go straight up lifting off the SSR and following the roof of the port. Note how 2/3rds of the exhaust port is hardly even being used. This is what I thought was going to happen, so it's cool to see the confirmation. Even though my exhaust port/valve is small, I think it's going to move as much air as a standard BBC port just because the exhaust air won't have to stall on the roof of the exhaust port/bowl and try and turn 45 to 90 degrees to continue out the exhaust port like a standard exhaust port.
Exhaust Port 151.jpg
Re: New SBC Manifold with tooling
Posted: Tue Jun 18, 2019 4:24 pm
by JoePorting
Cylinder Head V5.2 Picture.jpg
Here's what the top of the head looks like. The valve cover is .600" wider than stock, so I figure if I'm going to require a custom valve cover I might as well use 10 bolts. The rocker area is made for max strength. There are two oil drain back holes on either end of the head in case someone wonders how the oil is going to drain. The head uses a standard Stahl pattern spreadport 23 degree header, although the exhaust ports are about 3" taller than stock and about 1" further out. On the intake side it uses a standard SB2.2 valley tray with my custom intake. So I tried to make this as standard as possible without the use of special cams or headers.
Re: New SBC Manifold with tooling
Posted: Tue Jun 18, 2019 6:44 pm
by Warp Speed
Where is the spark plug positioned?
Re: New SBC Manifold with tooling
Posted: Tue Jun 18, 2019 11:53 pm
by JoePorting
Warp Speed wrote: ↑Tue Jun 18, 2019 6:44 pm
Where is the spark plug positioned?
At the far side of the combustion chamber, not the middle.
Re: New SBC Manifold with tooling
Posted: Wed Jun 19, 2019 8:58 am
by Warp Speed
Those ports and resultant layout look like they could move some air for sure. But as I've mentioned before, the chamber and spark plug placement will be the downfall of this design.....
Re: New SBC Manifold with tooling
Posted: Wed Jun 19, 2019 10:58 am
by JoePorting
What sort of power loses have you seen from bad spark plug placement?
Re: New SBC Manifold with tooling
Posted: Wed Jun 19, 2019 12:24 pm
by Warp Speed
JoePorting wrote: ↑Wed Jun 19, 2019 10:58 am
What sort of power loses have you seen from bad spark plug placement?
Between the chamber and plug, it could easily be 100+ in a running engine. Maybe more. There is a reason no newer cylinder head has a chamber or plug location that is similar in design. Only time will tell I guess.......?
Re: New SBC Manifold with tooling
Posted: Sun Jun 23, 2019 3:49 am
by JoePorting
CombustionChamber1.jpg
CombustionChamber3.jpg
Here's some pictures of the combustion chamber from the billet heads that Pete Adams at QMP Racing did over a year ago. The valve sizes are 2.35/1.5 and the valve spacing is .125"/.250", so the valves are far over as you can tell. The exhaust valve is so far over that it is in the side of the 4" chamber wall, but not into the head gasket area. This is what I call a "Side-Flow Combustion Chamber" because the air actually flows sideways all the way around to the far end of the exhaust valve. When I tried filling in the far side with just .100" of epoxy on the flow bench model, it actually lost 4 CFM which is telling me the intake air is actually going all the way over to that side. But I think the advantages of this chamber go beyond intake flow, since the entire chamber is exposed to the intake air, the entire chamber should "Air-Cool" from the fresh intake charge. The top of the exhaust valve should also air-cool. This head should only produce heat from the exhaust port only. With the large water ports in the head, this head combo should run really cool.
Since the roof of the chamber is all flat, the flame front from the spark plug should travel across the chamber roof in a fast/even manner. I know many people are going to say that it should be in the center of the chamber, but I think it's going to work fine where it is. The spark plug is also exposed to the intake air, so it should stay clean after each combustion cycle.
Also note that the valve center-line is nicely centered in the combustion chamber. Stock SBC heads have the valve center-line over toward the sparkplug side of the chamber by about .200". The intake should flow 500 CFM with a 55 degree seat. It currently flows around 475 with a standard 45 degree seat.
Re: New SBC Manifold with tooling
Posted: Sun Jun 23, 2019 8:42 pm
by zums
JoePorting wrote: ↑Sun Jun 23, 2019 3:49 am
CombustionChamber1.jpg
CombustionChamber3.jpg
Here's some pictures of the combustion chamber from the billet heads that Pete Adams at QMP Racing did over a year ago. The valve sizes are 2.35/1.5 and the valve spacing is .125"/.250", so the valves are far over as you can tell. The exhaust valve is so far over that it is in the side of the 4" chamber wall, but not into the head gasket area. This is what I call a "Side-Flow Combustion Chamber" because the air actually flows sideways all the way around to the far end of the exhaust valve. When I tried filling in the far side with just .100" of epoxy on the flow bench model, it actually lost 4 CFM which is telling me the intake air is actually going all the way over to that side. But I think the advantages of this chamber go beyond intake flow, since the entire chamber is exposed to the intake air, the entire chamber should "Air-Cool" from the fresh intake charge. The top of the exhaust valve should also air-cool. This head should only produce heat from the exhaust port only. With the large water ports in the head, this head combo should run really cool.
Since the roof of the chamber is all flat, the flame front from the spark plug should travel across the chamber roof in a fast/even manner. I know many people are going to say that it should be in the center of the chamber, but I think it's going to work fine where it is. The spark plug is also exposed to the intake air, so it should stay clean after each combustion cycle.
Also note that the valve center-line is nicely centered in the combustion chamber. Stock SBC heads have the valve center-line over toward the sparkplug side of the chamber by about .200". The intake should flow 500 CFM with a 55 degree seat. It currently flows around 475 with a standard 45 degree seat.
Well, i have to give it up to you for getting your idea cast, but the chamber looks like 60 yr old technology, what makes you think you wont have severe plug wetting, the chamber will have zero pressure recovery, have any of the design parameters of the chamber been dyno tested or has it been designed purely from the bench.
Tom
Re: New SBC Manifold with tooling
Posted: Sun Jun 23, 2019 9:03 pm
by JoePorting
I've never seen a chamber like this before. The chamber walls are designed to give a seem less transfered to the cylinder. I found most pressure recovery comes from the top angle of the valve job which is 35 degrees and .100" wide in this case. All this design is from a flow bench, so the first Dyno test will tell alot.
If this test doesn't work good, I can change the printed Sand core and go with a different chamber design.