Let's see some pics of those homemade intakes. I am planning a straight 6 build and was going to put maybe 5 or 6 carbs down the side of it on a scratchbuilt intake. how did some of you guys do it and what are some of the pros and cons?
Here are some good ones... http://www.jalopyjournal.com/forum/showthread.php?t=319420&highlight=homemade+intakes http://www.jalopyjournal.com/forum/showthread.php?t=431889&highlight=homemade+intakes
There, Some I have done and some I am doing. I make it out of wood first . You might be surprised to find how many little things you can sort out with $5 of wood so when you get to the real deal all the measurments and angles are right. Proper tuned length for a plenum type manifold is approx RPM in thousands divided into 90 (From PH Smiths book Design and Tuning of Compe***ion Engines and Irvings book Tuning for Speed.) gives the length from the plenum to the back of the intake valve. It works pretty well i have found even though it is a rule of thumb. Don
I said "RPM In THOUSANDS" 5000 would be 5 thousands so 90/5= 18 inches. 6000 is 6 thousands so 90/6 = 15 inches 7000 is 7 Thousands so 90/7 = 12 6/7ths inches etc Don
Made this one in the 90s , top only. Worked good. Same time exactly in wood as in aluminum. I know it isnt 6 cyl but the principles are exactly the same.
Here's mine for a 582 chevy. I just built the top the bottom is a dart single 4 barrell manifold that I machined off.
Here's a couple pf pretty ugly ones built by an Chet Smith on an olds mill. They are pretty ugly and the runners are pretty short. So I'm guessing that Chet was looking at turning a lot of Rs and didn't think anyone would see them for very long.
Maybe but not every intake has a proper tuned length. It is not a well understood deal. Sometimes folks were perfectly happy just to be able to run 2x4s and that is fine as well. Don
I don't think that Mr Smith was an induction guru and he was just trying to get enough air in to go with the rest of the build. One of everything has been done to this mill a lot like the little motor in your zinger. I personally would have done some things different with them but I'm going to run 'em like pretty much the way they are for starters.They say that Chet won a lot of races back in the day. I want to see how it does before I molest it much. BTW you use the same formula my Ol Man used way back when he had a different formula for plenum size but I have been having a helluva time locating it. I will though.
I drew this up to help anyone who might want to build their own intake, I also found that the 2 center bolts on intake gaskets are no longer in line with the others. Apparently the gasket manufactures raised the center holes to make the gaskets universal to also fit Vortec heads so keep that in mind when using gaskets as a pattern. The last change I'd do if I were doing it again is mark my 3" hole saw center at 6 3/8" to give me some material to fit the log, I checked it with the hole saw simulating a 3" log, looks good and we'll see how it fits this week. See my complete build ............. http://www.jalopyjournal.com/forum/showthread.php?t=533613
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