I've got a spare set of irons I'm going to get a good port job done on before I dive into my "production" irons. I've been staring at my templates for a while now... a bunch of howtos on porting... And here are the ports I've come up with. So far just the secondary/aux ports... I probably won't end up doing much to my primaries at all... just cleaning those up.



I'm thinking I can go a bit furthur on the aux ports, but no template I've seen goes out that far... whats the reason for this?

Thanks in advance for your advice.

 

So, since the secondary ports are always open, I'm going to go ahead and go a little less conservative on my primaries... Not sure what I was thinking.. Secondaries are open as long as the primaries are.... But, the aux ports are where I want to go as big as possible since those are the ones that do open later and won't affect my low-rpm mileage/driveability.

 

What are you doing to you sleeves on the aux ports? It looks like your porting in farther than the sleeves go. Also, the sleeves have a flat bottom, verses your slanted port.

 

Probably a taper to the ports edge.... can't really mess with the sleeves at all since that'll leave the hole open....

 

It's almost pointless to port down. Just increases port volume which may not be a good thing.

That's a very late closing aux port. Probably better suited to high RPM operation. If you end up porting to the point where the port is still open as the rotor begins compression then you will blow some of your intake charge out the port and likely disturb airflow. Rotate a rotor across the template and make sure the chamber volume doesn't start decreasing while the port is open, and that no seals catch as well.

 

I put a rotor on it yesterday.. but I was just checking the seal paths... I'll do that again later.

but, better suited for high rpms.... thats the only times the aux's are open. This will be a fully functional 6-pi system...

Its still early for me... been sick.. so I haven't been getting a ton of sleep and I just woke up.. so.. Sorry if I'm not making sense.

 

Well, now that I've woken up, I figure I'll reply again.

Thats how late Kahren's 195rwhp ports close. I haven't touched the aux ports past what his template showed. I'm gonna toss a rotor on there in a minute and see how we're looking.

 

http://picasaweb.google.com/micaheli/Ports

I put a rotor and a housing on there... played around with it a bit. took some shitty pics. There's the link.

From what I can see, the volume of the intake cycle doesn't reduce (much) before the port closes. It just rotates. But IMMEDIATELY after the port closes, it starts getting smaller. I figure the velocity of the air will still be charging the chamber prior to close...

Whattaya think?

 

You should definitely put a sleeve into the aux port to make sure you aren't going past the sleeve. My port job was reasonably close to the end of the sleeve, and it looks like you are going a good bit past that.

 

If you intend to have functional sleeves, then you will be fine for sure.

 

I'm all about functional sleeves! And perhaps 550cc secondaries if I find my wideband leaning out in the high's.

Thanks for the input guys, being my first porting job, I'm gonna crank out some ports on some scrap irons with pitted o-ring tracks and see how well I do before I ruin a set of my good ones.