Pro-tip, airflow and light tend to follow similar paths. When you shine a light down a port you can often see more or less where vortices form because of how the light reflects off the metal. Tight lines tend to form vortices, and these vortices help flow stay attached, but also acts like virtual bodywork that air has to flow around. The interesting thing is that air flows around vortices with very little energy loss, which means where the flow would typically detach and go turbulent, a vortex will keep the flow attached with less momentum loss.

@WeingartnerRacing You remind me of my old friend #LarryMeaux from Meaux Louisiana 💪👍👌

I first read and followed smokey yunicks porting instructions then my machine shop buddy from school put me onto chad spieir and after watching many of your videos i find alot of commonalities that each back all 3 up and those things are the things i store in memory and put in stone when i do any amatuer porting myself....always good info and if just a little a person didnt know prior to watching the benefit goes a long way when every little bit counts......i appreciate your efforts very much and appreciate you dumbing down your words so a pleb like me can understand without smoke emitting from my ears

Watch every video and your information is bar none, great work!!

It's almost like wet flow, reversion, port bias, and fuel dams matter and are incredibly difficult to predict. Flow transition as the valve moves makes it a, pun intended, moving target to acheive higher efficiency at all lifts instead of just one static lift. I thoroughly enjoy your tech videos even though I rarely do Chevys.

The guide vane produces a horseshoe vortex and the vane is there to keep the vortex from merging, this vortex keeps flow attached to the roof. You do a good job with the vane, the vane helps guide the flow into the chamber from the roof side. If the vane is pointing away from the plug you very well could wind up with swirl reversion.

I always check distributor alignment first and then mark out intake from that point pretty tough to have intake line up on on multiple engines not many people go through this step but helps remove distributor fluctuations

Eric great info, thanks

We have a pulling tractor that was dynoed and then we pulled the head off to put in new rings. When we took intake off we noticed the intake gaskets were hanging out into the port so we trimmed out the gaskets and put in new rings and put in new valves. When we took it back to the dyno it was down on power by about 50 hp. So we checked everything and couldnt get the power back up to where it was. We took the intake off and put new intake gaskets on that were again hanging out into the ports and the power came back. Why would that be? Ports too big?

Oh wow sounds good on the heads

Carbon pattern in the chamber looks nice though, its hard to keep the intake side from being lean, I feel that fin and the low pressure might be helping pull fuel to the lean side and using more of the valve area. I like the way you are testing this, and waiting for the next video.

Keen to see the 406 with the tall 1207 bastard port heads and with wide pinch offset pushrod heads. Gunna need one of those to run with the LS 408 I suspect.

I struggled with getting 1206 to seal on my sbc with dragonslayer heads. I switched to 1207 and notched the port roof on the gasket and it has sealed up completely. Intake and heads were ported to match a 1206 but even the 1207 didn't fully clear my port which is why I trimmed them up. I had 2 problems 1 ports are bigger than gaskets, 2nd problem was bypass coolant port on brodix head would hold gaskets up in the middle

Flow bench is a constant vaccume .. on the running engine the flow turns into pulses and acts quite different throughout the range of throttle.. need some fairy dust and a bent stick to completely understand air flow in ports on a running engine..😂😂

A fuel trail indicates a low pressure area somewhere. It could originate in the intake, then the fuel could travel into the head already condensed. Seems to me, you'll always be fighting this sort of thing unless the runner is completely straight, void of any restrictions or bends.

The fuel line seems to follow the angle of entry on the pushrod side of the port, I wonder if the air speed and angle of flow coming in at the pinch could cause that?

Eric, I was one that said that I can't trust your intake manifold comparison, at least in a fine sense. The reason is that when I build an engine I always check intake port alignment and do whatever is needed to get the location of the port to line up as well as be the same size. I don't think anyone that's serious about maximizing their build just bolts on a manifold after gasket matching it and think they got everything the parts could provide. I do understand that you might not have been able to modify manifolds others bought for this test. I do see that you held the 1206 gasket constant - a good thing! But here's an idea for future testing: Build the shortblock a bit shorter than the standard deck height and either use different thickness gaskets or AL spacers so that you could custom fit each manifold to the shortblock so you could take the port location or alignment mismatch variable out of the comparison. Just a thought, and I do realize that's a bunch more work. But then you'd have data that people could really use to compare the manifolds only and not have the setup variations screwing up the comparisons. Besides all of that, I'm really interested to see what your new port work does for these heads. 23 degree SBC stuff will always be interesting to me!

Eric Weingartner, would it be a good idea to put a wing where the fuel trail is?

How much does the angle of attack of the intake runner on the manifold have to do with helping direct the flow to one side of the port or the other ? I wonder what kind of tricks could be done in the intake manifold ? I know it’s endless you can do just about anything but as usual you need to be testing small changes on the Dyno or race track that takes a huge amount of money to do that kind of testing, nascar, comp classes, prostock level development I think it would be amazing to be a part of a team that had an unlimited budget to figure out how to get the most horsepower out of a certain combination

Is the 4 o-clock vein position an attempt at slowing down swirl?

Amateur question here... Wouldn't you want the vane pointing towards the spark plug for best power? It also looks like that would continue the natural swirl from the intake port and help the cylinder fill (or so Suzuki claimed with their twin swirl combustion chamber back in the day).

Since you got all sorts of dyna data to go off of, I was wondering if you would experiment with CeraKote C-series PistonCote on your piston tops and on the inside of the exhaust ports. I do this to all my engines, btu I have no idea how much if at all it is helping me. I assume its helping the temp, but I have so many mods I do it is hard to tell. Most everything I work on is diesel though.

They always forget about core shift in casting and different companies. Thats why I believe hand porting is better. You can accomodate for core shift.

Hey Eric, completely off topic, but i sent you an email again about doing some head work for me. you said you sometimes miss emails but do tend to read the comments so i thought i would give a heads up. its for a set of oddball ford heads. thanks and keep up the good work.

Audio fine

Have you ever checked out mast motor sports LS heads

If you hold to the theory that air is a fluid. Why not help the air flow, swirl clockwise from the intake to the valve? At least in the northern hemisphere.

Eric, I always assumed the wing there was like the Glidden wing on the short side and was more of a wet flow issue.

Do you ever reverse flow test your ports? And you have not talked much about the swirl meter you got

Chasing the 101st % is all ways going to be a torment.🤬 .. there's only so much you can do with a 1950s engine that puts one arm firmly behind your back.. I'm none the less impressed with your dedication.

I think the fuel is migrating toward the bias of the port. It tries to flow to the least path of resistance. Tell me if I'm wrong.

No disrespect intended but if the ports don’t align it’s not port matched. It might be gasket matched.

Here before the thumbnail

Did you ever test the roval AFR intake on the big block chevy?

I thought you wanted your port area to be biased to the cylinder wall side of the valve since that is the straightest shot? Which looks like where the flow is going from the fuel trail? I may be dead wrong just poor boy logic

You do realize that your video just ends instead of going to your second talk over

Here before the audio renders

Very silent

I struggled with getting 1206 to seal on my sbc with dragonslayer heads. I switched to 1207 and notched the port roof on the gasket and it has sealed up completely. Intake and heads were ported to match a 1206 but even the 1207 didn't fully clear my port which is why I trimmed them up. I had 2 problems 1 ports are bigger than gaskets, 2nd problem was bypass coolant port on brodix head would hold gaskets up in the middle