PB blaster, or let is soak in some purple power. They will come apart, I take them apart all the time. You will need to buy some high temp gasket sealer to put it back together though. How did you get the plastic things out without taking the plenum apart?
I just took an N/A plenum apart today. Those are the longer runners in mitsu's variable runner length design. It's pretty cool how it works. The physics behind it is even cooler - namely the organ pipe theory. When the intake valve opens, it releases a negative pressure pulse (i.e. sound wave) up the runner. When the wave hits the top of the runner, most of it continues into the plenum but a certain % of it is reflected back down the runner as the inverse - a positive pressure wave. When the engine is at the right RPM, that positive pressure wave hits the intake valve right when it closes, thus forcing a little extra air into the cylinder and improving volumetric efficiency (POWER).
The reason for the dual lengths is that at lower RPMs, there's more of a lapse between intake valve openings, therefore the longer runners allow the stronger first or second pulses to synch up ... whereas at higher RPMs, the valves within the N/A plenum open, cutting down the runner length considerably, and working with the shorter lapses between intake valve openings.
I just took an N/A plenum apart today. Those are the longer runners in mitsu's variable runner length design. It's pretty cool how it works. The physics behind it is even cooler - namely the organ pipe theory. When the intake valve opens, it releases a negative pressure pulse (i.e. sound wave) up the runner. When the wave hits the top of the runner, most of it continues into the plenum but a certain % of it is reflected back down the runner as the inverse - a positive pressure wave. When the engine is at the right RPM, that positive pressure wave hits the intake valve right when it closes, thus forcing a little extra air into the cylinder and improving volumetric efficiency (POWER).
The reason for the dual lengths is that at lower RPMs, there's more of a lapse between intake valve openings, therefore the longer runners allow the stronger first or second pulses to synch up ... whereas at higher RPMs, the valves within the N/A plenum open, cutting down the runner length considerably, and working with the shorter lapses between intake valve openings.
Pretty cool huh??
V-TAK JUST KICKED IN!
Seriously though, that's awesome info. Thanks, Ryan. You learn something new every day.
I just took an N/A plenum apart today. Those are the longer runners in mitsu's variable runner length design. It's pretty cool how it works. The physics behind it is even cooler - namely the organ pipe theory. When the intake valve opens, it releases a negative pressure pulse (i.e. sound wave) up the runner. When the wave hits the top of the runner, most of it continues into the plenum but a certain % of it is reflected back down the runner as the inverse - a positive pressure wave. When the engine is at the right RPM, that positive pressure wave hits the intake valve right when it closes, thus forcing a little extra air into the cylinder and improving volumetric efficiency (POWER).
The reason for the dual lengths is that at lower RPMs, there's more of a lapse between intake valve openings, therefore the longer runners allow the stronger first or second pulses to synch up ... whereas at higher RPMs, the valves within the N/A plenum open, cutting down the runner length considerably, and working with the shorter lapses between intake valve openings.
Pretty cool huh??
+1
This is corrct. Those black pcs in you hand create a velocity stack opening at the begining of the longer but smaller diameter runner. this allows for grater air speeds and volume in the smaller runner. The NA intakes are made by and designed by Mikuni for mitsubishi. Mikuni make most of your bad ass bike intakes and this system they did for the NA is top notch. This is good stuff your looking at. This system can not support the big cams that I have and head work that I did. But I will never be able to get the low end torque back that I lost when removing this system. Now I can not just put it back, because now all the runner length are wrong for me. Win some, lose some.
+1
This is corrct. Those black pcs in you hand create a velocity stack opening at the begining of the longer but smaller diameter runner. this allows for grater air speeds and volume in the smaller runner. The NA intakes are made by and designed by Mikuni for mitsubishi. Mikuni make most of your bad ass bike intakes and this system they did for the NA is top notch. This is good stuff your looking at. This system can not support the big cams that I have and head work that I did. But I will never be able to get the low end torque back that I lost when removing this system. Now I can not just put it back, because now all the runner length are wrong for me. Win some, lose some.
I actually used Mikuni ITBs on our FSAE R6 engine in the midst of learning all that fun stuff.
Thanks for the lesson lawdogg i'm just out of high school ap physics and am happy to see it applied to everyday hobbies and passions aka CARS. Unfortunately part of the pieces that secured it to the plenum was broken sort of tabs to hold so i left one of the 6 out... Assuming that's ok based on some of the other comments here?? Just figured it'd be better short one than having it flopping around in there if it came loose again. Let me kno if not...
Unfortunately the reason this all came about (replace plugs and wires) didn't solve my engine misfire so it's back to the drawing board... If people are still willing to help that'd be great i'm going to describe my problem and figured maybe one of you vets could help me out. Thanks again to everyone...
At start usually seems ok. Sometimes not after running hot it struggles to keep RPM's up. After it has been cooled down it's ok but after a couple of minutes begins the jerk and just gets progressively worse...
Mechanic said definite misfire and to start w/ plugs and wires so that's done. Seems better but not perfect. It actually got better the more times I started it but had to stop b/c a little loud this late at night. When i bought car it had no spark and i was checking and replacing things then so this is what i believe could be ruled out... ECU and PTU was bought used from reliable source to my knowledge and i checked coils using the check from stealth316.com.
What else could it be??? Mechanic also told me to take a look at Mass air flow sensor so i was going to do that next unless anyone has a better route here...
Thanks again
do you have a datalogger? if so, you should be able to turn off individual cylinders and see which one is possibly misfiring. It may end up being the one with that missing piece
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Re: 6 Big black plastic pieces inside my plenum??
<<3750 pound beast.
Now I can not just put it back, because now all the runner length are wrong for me. Win some, lose some.
