how much are you going to cut the runners down? I did 1.5" for my 360 and based on the results, it worked pretty good. for a 318, I'm not sure how much to trim...

 

From what I read, I think about 1"-1.5" should be about perfect, escpecially since I have other mods.

 

If you take out the center plate, there is no need for "strengthening" the intake. Trust me, that plate has nothing to do with structural integrity.

 

I didn't think so either, but it was lingering in the back of my mind. I'm not going to worry about it. Just means I have more material to remove is all.

 

I'm thinking about like this:



[IMG]local://upfiles/9095/DAAC24EBC3BA413DA27F4B002379DC3B.jpg[/IMG]

 

But i'm also tempted to try something like this. Seems this would allow more air to enter the inward facing opening of the runner, allowing it to get more of the air that is in the middle of the intake. Thoughts?

[IMG]local://upfiles/9095/FD996637A5EE4BBCA39E4FA4A6EDCA98.jpg[/IMG]

 

Yep. Did you check out my Engine Build Thread #2?

 

I'm not too sure how much of a difference the 2nd pic cut would make... you would be possibly pulling in cooler air on the inner cylinders since it would be more ofa straight shot from the TB opening. it could be the designers did it that way to heat up the air some before it enters the runner by pulling it past the plenum plate. now what would be interesting to see is if there is any difference by insulating the bottom of the plenum on the inside of the intake somehow. this should keep the air in the intake cooler, similar to having an airgap type of manifold from edelbrock but obviously with the longer runners by design in the kegger.

 

Ya, unfortunatly, I only want to do this once. Not several times, testing different cuts.
Everything I have read indicates that because the 5.2 is smaller cubes, it needs the runners to be longer to help fill the cylinder better, escpecilly at low rpm. Cutting too much off moves the power curve higher. So I really don't plan to do too much, just enough to make it better the the stock intake.

What are your thoughts about cutting out the hole where the TB bolts to so it is just one single hole instead of two barrel shape. Seems to me that could cause the air to start getting turbulant too soon. The barrel shape on the intake probably keeps the air pretty uniform going rom the TB, through that hole, then into the actual open area of the intake.

Thoughts?

 

I don't know that cutting that out would make a huge difference because the holes in the TB are the same size or smaller aren't they? That would be your restriction.You night run into a harder time trying to seal your tb to the intake and have an annoying whistle. I got that from simply trying to reuse a TB gasket, I can imagine it would get more difficult with less platform as well.If anything I would think maybe round off the bottom edges of theinside of the intake at the TB hole to start an immediate expansion into the intake, it might mimic those "filler ramps" to a lesser degree.