If you do a street port and open up the aux ports then the aux port sleeves will have a little bit of overhang, obstructing the wider (or taller, depending on your phrasing) port. Do you then need to widen up the aux port sleeve opening? This will mean that the sleeve will begin to open the aux port a little early, but if you've ported the aux port, you might want that anyway.

 

I don't know of any issues with doing so. people program their stand alone's to open them earlier all of the time. Besides, the port is only going to flow as much as its greatest restriction will allow.

 

that's kinda what I figure, I just thought I'd ask just in case I was about to do something really dumb.

 

I'm going to "port" my sleeves as well.

 

I'd recommend being VERY conservative on the 6 port irons for any kind of street port.

Port the primaries about 3MM up and 3MM down, but don't open them earlier.

Open the secondaries 2MM earlier, and open the aux ports 2MM earlier.

The 6 port engines already have a massive amount of port area. By opening it up, all you do is reduce low end, shifting the powerband out of the efficiency area of the stock intake manifold.

 

If you port the aux ports and open the sleeves up to match them, when the sleeves are in the closed position they won't actually be completely closed as the enlargening will now overlap the intake port. Hold the lower manifold up to the end housing with a sleeve installed and rotate it from the aux port valve rod. You'll see exactly how much larger you can go over stock before you hit this problem. To save some time, the answer is none. Aside from a bit of port runner cleanup, the only real place you should worry about port work on a 6 port motor is on the primaries although you can open the secondaries a little bit earlier.

 

Hmm.. I did do this and marked the irons. It looked to me like I had about two or three mm worth of rotation before the sleeve started opening to the port. I guess I'll have to re-measure to make sure.

 

From an airflow point of view, how bad is it to blow into a dead end cylinder , then come out the side at a 90 deg angle? Very poor airflow. What's the appeal? Cost? Simplicity? Challenge?
I'd go to a Turbo side hsg.

 

Pineapple makes a fix for that.

 

Pineapple's fix kinda scares me. Those inserts are held in there just by bending the sleeve lips a bit. I'd be paranoid that one would slip out a bit and into the rotor housing and destroyOboy.

I did the measurements again and ended up taking off nearly 6mm of radial distance. I guess that port is on the larger size. The sleeves now just barely close the ports off when closed and have a little room at the top when open. The sleeves came out pretty good for using a wood clamp, some vice grips and a dremmel, I think.

 

I called them about this before I ordered mine. First, you scratch the inside of the sleeve and apply some locktite, than slide the inserts in. Last, you bend the edge to ensure a tight fit. They don't get hot enough to actually warp the metal and send the inserts directly into the housing(if you didn't port the sleeve). Maybe too late.

Hope I helped!

 

Thoughts on bridge port on the aux ports only?

I've started tearing down motors, and thinking about porting. I've already ported and polished the bends in the intake manifold. So do a street port on the primary and secondary ports. then a bridge on the aux ports. For the sleeves, port the leading edge only, and use the Pineapples.

The sleeve inserts don't break apart or anything. If you properly scuff the contact surface and use adhesive, they will not com out.

 

No.

In fact, most people porting 6 port irons for the street would be better suited to just leave them alone, or be very conservative by doing what I mentioned already in this thread.

Going any larger just reduces low end and midrange, and moves the powerband up to a point where the stock manifolds aren't designed to operate.

On that track it may be another story, but there is a big difference between a track and street car (which I wish more people would consider).

 

Aaron, you don't seem to be taking into account the fact that the aux ports open later. Street-port the 4 ports, then bridge the aux.

Seems like a great idea. Until someone's done it, I wouldn't see any reason to knock it.

If the aux ports don't open till like 3500-3800rpm, keep your revs down and you retain the streetability of the street port. Get on it, the ports open up, and you've got FLOW. If the stock mani's can't handle the flow...more upgrades. It's not a hard concept, port/polish the stock mani's or get some custom.

 

Do not bridge the auxiliary ports. It sucks! No one has ever made good power with this setup. It sounds good on paper but in reality it isn't. The flow through those upper ports is terrible due to the turbulence from the control rods being in the air stream. A bridge needs great airflow to work well. People have argued time and again why they think it will work or why it should work and every single one of the have been proved wrong in the end. Just say no to aux port bridging!

The Pineapple sleeves can't fall out. Due to their shape it is completely impossible. The worst thing that could happen is that they come loose and slide back and forth within the sleeve. There has been one engine failure attributed to the sleeves but it was actually installer error. The pin that gets removed to get the sleeve in only fits one way. If you try to punch it in the other way, it may go but it won't be secure and can potentially fall out. This did happen on one engine and the pin got ingested into the engine and took that rotor out. This was in an airplane engine at altitude which is not a place to have a failure due to your mistakes. If you follow the instructions, you won't have any issues.

 

Thanks for the info on the Pineapple sleeves. I won't be able to do that though, since I've already "ported" my sleeves.

 

Well, give it a shot and if the gain isn't what you wanted or if there was a power loss, then those sleeves are pretty cheap to replace.

 

Having not ever run this engine before, I won't be able to tell loss vs. gain. It just seemed like the thing to do.

 

And their opening/closing timing is exactly why just bridging the aux ports isn't a good idea.

If you want to bridgeport a 6 port engine, then use standard bridgeport timings on the secondary/aux ports. The bridge will cover about half of both ports, but won't go to the bottom of the secondaries and won't go to the top of the aux. This will result in an engine with a higher powerband then a 4 port bridge, but will still work very well. Assuming you change the intake manifolds...

I've done it. Any more questions?

 

Hmm,
Auxiliary bridge port sounded like a good idea.
I thought that if you ported the primary and secondary ports, then had the bridge aux ports open later, say 4500 rpm, then you could keep the bottom end and have the upper range too.
I don't know, I haven't tried it. But it seems logical. I'm not trying to argue or anything. just a discussion.
didn't mean to thread jack.

 

That's what logic says for me too.

I found Aaron's build where he did this with a turbo...but we're talking N/A.

Who knows.

Every engine and builder is different. I might do it myself, just to do it

 

It's been tried in NA form quite a few times and the results are almost exactly the same every time: more or often less power then a street port. By bridging the aux ports only, all you are adding is overlap and not really any flow.

In my case it's a bit different...my car is turbocharged and I have a custom intake manifold. But going back in time, I'd have been far better suited to have done a proper bridgeport.

 

i still don't believe in the port sleeve inserts anyways.

i've made 190whp on an S5 n/a without those funky inserts with stock manifolds, the air doesn't touch the backside of the sleeve anyways, only a tiny bit of air will hang out there and act as a cushion in aiding the air move past the port so in essence the inserts can actually hurt performance.

rotary porting is about making the airflow path the most direct and straight as it can be, think peripheral port and it's path and understand why they make the engine so much more efficient.

 

Please explain how it's adding overlap in the lower rpm's if the valve is closed.

Karack...the sixth port adds top end breathing while retaining low end velocity. You need velocity for torque, but flow for hp. The 6th port adds flow up top without sacrificing velocity down low. Slight restriction adds velocity...when done right. Rotary porting is about using port shape/size/placement to get the flows and timing you want like you would with a cam and valve sizes in a piston engine. The biggest difference is, if we screw up we can't just go buy a new cam.

I'm NOT saying to bridge the aux's and remove the sleeves. I AM saying to bridge the aux's and the sleeves but leaves the sleeves in place and operable, that way the aux bridge is closed at low rpm then opens up and adds overlap and flow to the upper rpm range.

If one were going to bridge the aux's and remove the sleeves, then yeah, just do a full bridge and kiss your torque goodbye.

I'm not a n00b to the theory, fundamentals and building of engines. I've built my share of racing piston engines. I understand flows, timing, pressures, harmonics, etc. Do you know how to tune your i/e runner lengths for specific rpm ranges for racing applications or daily driving? I'm not trying to sound elitest, just making it clear I'm not some dumb n00b to engines.

 

you sure are sounding elitist to me.

we're now getting way off topic of the point of retaining the 5/6th port sleeves to sacrifice low end for top end, there is no need to overthink the simple things.