Intake + sawzall =

MiaTurbo

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FSM 1.5.b "Kluge";FSM-SV "Ramalamadingdong"; Civic High-Bread
:) In keeping in line with my more efficient theory, I hacked up a extra intake manifold. It's a track car and turbo'd so I didn't care about torque building long runners, it'll live above 4krpm. So I also got some 3"x2" aluminum tube stock, a 65mm mustang throttle body(29% bigger than the stock 55mm), and upper manifold from a 4.6l. more picture to follow...
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Fadi, is there anything you haven't modified with a sawzall yet on that poor car? ;)

I'm looking forward to where this is going.
 
Turbo miatas are almost as cool as IRTB miatas :p

Can't wait to see what you end up w/ on this fadi. Sounds like you've got a good plan :D
 
So today I basicly evened up the runner 'nubs' to make tham all even, cleaned up the extra metal from the no longer needed supports for the upper plenum, and started to smooth out the entry to the nubs where it will join the new plenum. I also trimmed back the 'ribs' on the lower side of the nubs so that I can get a good bead around.

2 problems so far:
1: I highly recomend getting the runners cut with a band saw. it was a pain getting them even.
2: I should have left about another 1/2" of runner from the stock manifold. Where the new plenum will be, and the new t/b it will butt right up against the fuel rail. Just a minor headscratching to problem solve will fix it :)

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head scratching done :) I just need to turn the throttle body 90 degrees so that the shaft is parallel to the engine...
 
OMG..... Im not sure I would have had the guts to try that out. More power to you. I cant wait to see the finished product.
 
It'd be interesting to see what a manifold with equal length runners and no collector would do. Is it too late to change your course of action? :)
 
what do you mean by no collector? The way I'm building it is the throttle body will be between #2 and 3 cylinders to help equalize the flow between #1 and 4
 
Oops, I should have been more clear - I meant no collector pipe. With an equal length runner installation, each of the tubes would join at the throttle body, much like that of the GM Quad4 LD2 engine.

Attached is the only image I could find of the thing, but it'll do. If you're interested, I can get detailed pics of the manifold at work tomorrow as we have a bunch lying around the shop.
 

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kcbhiw said:
Oops, I should have been more clear - I meant no collector pipe. With an equal length runner installation, each of the tubes would join at the throttle body, much like that of the GM Quad4 LD2 engine.

Attached is the only image I could find of the thing, but it'll do. If you're interested, I can get detailed pics of the manifold at work tomorrow as we have a bunch lying around the shop.
ahh, i know exactly what you're talking about. They have the same type of intake on Toyota Previa vans.

This is my understanding of intake manifold design: long runners are needed on N/A engines to build intake charge velocity under negative pressure. It's needed to help build torque down low, and you need the runners to be as straight as possible to reduce turbulance to help the upper rpm range to help develop horsepower.

Since my car is turbo'ed, and not too concerned about low rpms. With a positivly pressurized intake, you want as short runners as possible. With the positive pressure charge it makes up for velocity.

As far as the longer runners and no plenum in the design of GM's Quad-4 motor, i'm not sure how that effects things on an N/A motor.
 
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heh.. First mock up :) I decided to angle the T/B about 60degrees because sticking straight up, the elbow going into it would rub the hood. I was going to have it point to the side, but the intake would be too wide, and hit the shock tower (measure 5 times, and cut once..) I think this is a good solid ( first ) design (2thumbs)
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