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Decreasing Port Size

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Old 12-26-12, 10:14 AM
  #26  
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Originally Posted by Pettersen
Might be a stupid question, but has anyone ever done this to the sec ports on a 6port engine?

By that i mean removing the bridge on the sec ports and then filling in the port in the shape of that on a 4 port engine?
since the 6 ports are round, making a plug/sleeve would be pretty easy. reporting to be like a 4 port would be a little harder, because you'd be into the plug/sleeve (i think) interesting idea though.

with a bunch of fab work you might be able to have a notch in the plug and instead of having the intake close at 40 and 80, maybe its like 40 and 60?

or forget that, maybe you pick a good closing time (50-60) and have a port runner that's close to stock T2 but slightly larger?
Old 12-28-12, 05:52 PM
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The reason i'm wondering if it could be done is because i don't have a intake with working 5/6 ports. And i'm going to rebuild my 6port engine as soon as the semi pp goes in the car.

Would be great if there was a way to get the engine ported to suit a non variable intake better.
Old 12-28-12, 06:05 PM
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Should probably mention that my engine never had sleeves, but instead it had butterfly valves in the intake. Not shure if that means that the irons are different or not?
Old 12-28-12, 06:15 PM
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Originally Posted by Pettersen
Should probably mention that my engine never had sleeves, but instead it had butterfly valves in the intake. Not shure if that means that the irons are different or not?
Not sure, we didn't get those here. I'm fairly sure that those were Europe-only.

The aux ports in our engines are just flat-bottomed machined holes that flow absolutely horribly, and if you port them to not have a large reverse lip, you end up with closing timing around 85degABDC. Far too late to make any power anywhere.

Now I wonder. It seems like all of the bridge ported 6 port success stories come out of Europe. I bet your aux ports look a lot better than ours do.
Old 12-29-12, 05:28 AM
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I can take some detailed pictures of the irons when i tear down the engine.
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