No the upper intake divides a single runner into the two ports. The runners are divided side to side (in the plenum) and the cylinder firing alternates sides.
No the upper intake divides a single runner into the two ports. The runners are divided side to side (in the plenum) and the cylinder firing alternates sides.
The oval port motor uses a plastic intake like this.
Is the goal to keep those butterflies? I got the Volvo Variable Induction System (VVIS) on my Volvo working with a Summit Racing RPM switch, vacuum reservoir, a relay, 3-way solenoid valve, some plumbing, and wiring. Volvo intended for throttle position, RPM, and maybe some other perimeters to figure into its operation, but I manage with simply opening & closing it at a specified RPM.
I think the answer for you should be individual throttle bodies. 
Nope I have the secondary butterflies covered with a cruise control servo and the megasquirt (rpm or TPS switch).
I have berkleyed the intake and I am looking to one up the better idea on the upper intake. I am not concerned with keeping any noise prevention technology and really want to improve low RPM torque on a under square motor with an aluminum flywheel. ITB's are not the answer to this situation. And I am building long tube headers to help on the exit end.
More progress today very happy with the fit.
Next is the clutch release fork pivot mount.
Not sure how I missed this. Great to see another awesome local build!
Probably mentioned somewhere in the thread..but where is the starter for this baby?
On top, rear mount, see the square hole?
Room for headers!
bentwrench wrote: On top, rear mount, see the square hole? Room for headers!
How convenient.
Oh! Yes! Your mechanic can change it at speed during a rally stage!
bentwrench wrote: Next lesson, intake manifold plenum volume and separation. I cut this interfering part off my intake. Being the more is better kind of guy I have this to install. On the last crap box I hot rodded (a first gen Neon) increasing the plenum volume produced a significant performance increase. The volume of the stock Neon manifold was easily twice what I have here on the Duratech. The Neon also responded to a larger throttle body well. Since in rotating the top half I was forced to remove the snout for valve cover clearance I have the opportunity to rework the volume and the configuration. For clearance I need to move the TB forward past the bumpy parts of the valve cover, I am also concerned about hood clearance. I have lots of room in front of the motor to do most anything I want. How can I determine how much to increase the plenum volume? Should I keep the tracts from the two plenums separate full length? I did not shorten the plenum divider and it appears there is a provision at the south end for an actuated divider door. I have a newer oval port motor in the wife's daily driver and it has a smaller plenum and a vacuum operated divider at the south end of the plenums. I don't think this was done for tuning reasons, I believe it was done to silence the droning from plenum resonance. (the Neon howled like a banshe at 5-6k rpm)(the wife's daily is very quiet). Which leads me back to my original inquiry, how much is too much and should I maintain division between the plenums? I also question the 2 different sizes of plenums seen here, the volume of the right side plenum is obviously significantly different to the volume of the left side! I always try to pray to the gods of symmetry, or is that just my OCD? Perhaps someone with a higher dork rating than I can make some sense of my psychotic rambling?
My understanding is the Duratec had a dual runner intake setup to basically change the effective length of the runners to coincide with optimal piston speed (RPM). Basically having the secondaries closed at lower RPM (<2800RPM if my memory serves me) increases runner length giving the cars better low end torque and after the IMRC's open it reduces the runner length resulting in better efficiency for higher rpm/hp. Best of both worlds. I would love to see the inside of the intake and see how far down the divider goes. Is the runner divided all the way to the exit?
I do not know much about intake volume but I would have to say if the volume is enough that the engine does not starve during operation increasing the volume would most likely not help. Changing runner length however will make a difference on these engines.
Closest thing I could find to explaining the purpose of the IMRC's quickly. I'm sure I could find more if you want. On my last SVT Contour my IMRC's were shot and would not open. I was limited to about 105mph on the track and it would buck and backfire like crazy until I had the controller replaced. Dyno'd something like 115whp. After the controller was replaced it went back to the dyno where it dyno'd 203whp. Pulled hard all the way to redline.
Thanks for the link. The IMRC doesn't change the runner length it just turns off one intake port at low rpm to raise velocity and chamber swirl.
The divider runs the full length of the plenum but is cut open at the south end, it appears to be setup for a divider actuator but just has a cover. The divider ends about half an inch from where I cut the manifold to remove the droopy TB part.
It effectively changes the runner length. Intake velocity is increased after the secondaries open to run more efficiently at higher RPM.
Man, that adaptor plate is a sweet piece. Cool project.
Very cool!
Made and installed the clutch fork pivot last night. Today made bracket for clutch slave cylinder mount.
The car is fairly rusty so I did not feel bad at all about doing this to it.
Measure twice cut once... There was a box on the motor side for the pedal hanger and a box on the pass side for the battery, bye bye. Hello blank canvas.
A little trimming here and there and the two are informally introduced.
This is pretty much on the original crank centerline, I need to look at the underside and see if I want to move it down any. Then I will temporarily hang it in place and put the car somewhat back together so I can scale it and get an idea of where the weight balance will fall.
Any idea on what Auto X class it will fall into? The rules are very hard to read. Maybe I want to move it back more and put the radiator in the back.
That's quite a bit of setback (heat, shifter/seat location, foot well size, etc.) for a street car?
A 2 door conversion is in the works. I have a pair of coupe doors to splice onto the front doors. I have seen others use the coupe doors but they are curved at the back edge and I don't have a coupe pillar. Not sure how that is going to work out, I am planning to eliminate the rear door, move the pillar back and make a pop out rear side window like the coupes and use a door skin to make the lower filler panel between the pillar and rear wheel to close up the remaining rear door opening.
I can put the shifter anywhere I want by fabbing up some quick linkage.
A lot depends on the rules, how far I can go with the motor placement... As best as I can determine for a front engine car no part of the motor can lie behind the mid point. But that may be too far back for a good weight balance F to R. Not sure if I want to go with a 50/50 or a 55/45 split.
IIRC, once you cut up the front wall you go straight to a modified class, where you will be eaten alive. Best to not get too concerned about classing with a project like this and enjoy playing with it wherever you land and enjoy the ride, IMO.
Bryce
Is there more than one mod class? Street tires?
Ha! There's no way you'll find a street tire class for this beast. Just go have fun.
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