Noooo....
Nobody has been able to port a LNF head...
All have failed...
You will fail, as it truly is 'rocket science' , to correctly achieve a ported LNF head that works better than a stock head.
Even if you have ported thousands of heads, over a lifetime, you will fail...
Maybe, just maybe, ZZP , has figured it out, after years of trying...

 

Understood, I guess I'll find out the hard way then cuz it's done. I will have a another head available once I change motors. I left the chambers alone I felt that messing with them would be asking for problems. The chambers and tops of the pistons look to be designed to move/swirl the air and fuel on the compression stroke. That being said I did not mess with them.

 

@RJ - I'll forgive the scale but you forgot Port 1! Not a big deal since we're leaving it alone. I just thought it was strange you drew in the intake tube without it...just a thought. Almost ready for another go at the leakdown test?

@Doc - I'll email you some pre ported pics. That way you can add them together as a before and after shot. Keep up the good work and as usual, keep us posted.

@2005HHR - that's way to many skulls! To say it's an absolute failure, I have to disagree. I find it hard to believe that it's impossible to improve the flow characteristics of a stock cylinder head, even the LNF. After having gone through my own, there are areas that could use improvement. Areas that casting left unsatisfactory, in my opinion. Even smoothing the rough spots and not completely porting have to have some gain.

This whole thread is completely experimental, I haven't seen my intake modification done before. Does that make it a failure? I certainly think not, "find a problem and fix it" that's been my motto. Same thing applies to cylinder heads.

 

Port 1? Port 1? 1.21 Gigawatts?

Great Scott, Marty, you're right!!



Guess I'm no Doc Brown

Too bad DrLoch didn't point that out, I could have said " Guess I'm no Doc, Doc!"

I had hoped to do another leakdown test after cleaning, before re-assembly, but I could not get any of the intake valves to seal. There must be little bits of gunk on the inaccessible parts of the valve seats. I'm going to run some more seafoam through the intake and hope that finishes the clean-up.

 

Everything we are talking about and doing is experimental and not for the feint of heart because sometimes it doesn't work. If a person is concerned about money and trying some of this stuff, my suggestion is don't do it, wait until others have figured it out. Education is expensive, very expensive in some cases.

When I was racing offshore boats if you couldn't walk up to a toilet and flush a $100 bill at any given time you had no business trying to compete.

Improvise, adapt and overcome.

 

I'd be interested in your findings, hopefully it helps. FYI, One thing I did notice on the head I'm working on is that the valves didn't look as though they seated real well, like the valves needed to be lapped to the seats. I'll be able to find out for sure if that is indeed the case when I start assembling them. I intend to lap the valves to the seats then.

 

A post that I found from 2010:
if you port the lnf head, dont expect a turn key solution unless you have a degree in thermodynamics

direct quote from matt at zzp...

"We found that the combustion of the direct injection is seriously affected by altering the airflow into the cylinder. Basically, auto makers spend millions of dollars to get the injection pulse placed just right and the incoming air has a serious affect on it. While we can gaurantee big airflow improvements, the tuneability is decreased and combustion is not as efficient.

-Matt "
per the OP:
basically, you can get more flow into the chamber, but power gains would be negligible, and streetability would most likely be ****. But i am not speaking from experience, im only piggybacking off of what matt said, so if you wanna try, please go prove him wrong

 

I missed your reason for installing the PCV after the catch can.
Also I don't see why you can't use a single catch can to do both area's?
Your relying on vacuum to move the oil vapor to a "can". Yes, two 3/8" ID hose has a greater area for flow into one "can" but being a science project, teeing the two to one and then letting the fresh/clean air return to both would be interesting.

 

A few minor reasons. Where the air enters the PCV valve, that side of the valve requires 1/2" hose. Where the air leaves the valve is 5/16" hose.

1. There could be a slight loss of vacuum transitioning to the larger 1/2" hose. I felt that loss might serve me well at the catch can, slowing the air and allowing the contaminants to drip a little better. Since it starts at 5/16" at the manifold and goes back to 5/16" on the way to the brake booster line, I'm not sure if the air would slow or not, but I think it will.

2. The fitting at the manifold that I bought was 1/8" NPT x 5/16" barb. I'm not sure if the hardware store had a 1/8" NPT x 1/2" barb, I wasn't looking for one.

3. I figured may as well keep as much of this clean as possible.

4. The 5/16" hose is touching the bottom of the airbox, a 1/2" hose would probably be less flexible and rub even worse.

On another note, the tee i found was barb, 1/2" run with 3/8" for the center. I had to take that 3/8 barb, carefully, to the bench grinder in order to fit the 5/16" hose on.

 

If you wanted to plumb it into one can, you would have to tee the manifold vacuum source (brake booster) to the boost condition vacuum source (turbo). You would need a check valve on each line, so that vacuum pulls from dirty, and not the other clean. Your PCV valve could be the check valve for the manifold line, as long as it seals. The ~10% leakage that DB is experiencing would not be so good in this setup, I think.

Now if you had a 2-valve can like the RX system, it would make it easier. I think I read a thread that mentioned that they have check valves somewhere in the system.