A&Q about 350Z
Q:
Im currently a student at Wyotech and in the upcoming weeks im going to have to put together a welding project and ive decided on an intake. My question is, where do i start when designing a manifold? Id like to design it for optimal performance in all conditions(tall order i know). This will be on a turbocharged L28 motor. Any advice or tricks are always appreciated.
Post Edited (Jun 26, 11:03am)
A:
Equal length runners to maintain velocity, individual throttle bodies are usually desirable for easy breathing, keep a smooth, but reasonable sized inner diameter on the runners, etc... Personally I'd like to see double or tripple throttle bodies on a single plenum feeding equal runners with the plenum being double layered aluminum with an air pocket between the layers for insulating. Would be an excelent intake for forced induction with an intercooler.
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77 280Z - TEC3 Engine Management, Coil Packs, 3.1 Stroker, 550CC injectors, tripple throttle body FI intake, MSA Stage II Cam, etc...etc...
79 Fairlady - Rusty
81 280ZX - DD
A:
velocity stacks inside the runners---
my thought would be to make (design) the flange first, then work from there....
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High Performance NA L28 engine, Performance Suspension, Full Interior, 2500lbs, and room for 3 HOT girls in the car!
shift_2+2
13.9 @102.7 on 205mm street tires and 110 octane :-)
A:
Shortest striaghtest runners possible with no plenum. Decreasing diameter runners with dual throttle bodies and a possibly a sync tube. Injector placement is critical although it's often discussed about here with different opinions. I say point them directly at the center of the back of the intake valve.
as said
Equal length runners
multiple TB's are good
A:
shortest runners equate high speed (say 10K plus)
longer runners give torque all the way down to usable range
for the Z 16-19 inch runners are close to ideal
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'74 2+2 -- MSA sway bars, Illuminas, Eibach Progressive, Energy Suspension
L28 with MN47, 240Z rods, milled down dished pistons (11.6:1 CR) and 240sx tranny
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committing suicide in small managable payments
A:
So show me the equation you guys used to come up with this "for the Z 16-19 inch runners are close to ideal"?????
Harmonic resonance needs to be calculated by Displacement, RPM max HP points, RPM max Torque points, and flow.
What Harmonic dimension is this "16-19, for z is best"?
ALL motors are different caluculate the harmonic for the best resonance with the least amount of sound waves per cycle.
Lots of Z cars, 1970's-1983's.
1977, Megasquirt, 12.8@ 105, 1.70 60 Foot, 2940 LBS. Blake Machine Co, Phx, AZ http://bandmzcars.com http://blakemachineprojects.com http://www.zselect.com
A:
Here is a quoate from a thread I wrote a couple months ago:
Harmonic resonance is when you tune your intake manifold to work at a certain RPM band. You want an intake that has the optimum flow for your head, motor, and power band. IDEALY you want a first dimension harmonic which means that you have only ONE sonic wave that goes from the intake valve to the end of the runner, at a give MAX HP rpm. Basicly what this does is create a super charger effect, thus giving more than 100% Volumetric Efficiancy (Wait, but this is a NA motor, how can you have more than 100% hehe). Ok, so like I said idealy you want a first dimension, but for our motors, that would be like 36" long, and that is sorta hard to fit under the hood of a car, so therefore we suffice and just go to basicly a 4th dimension harmonic on our intakes, which means the sonic wave goes from the valve to the end of the runner, and back to the valve a total of FOUR times. It still creates a super charger effect but it is not nearly as ideal as a first dimension. Sound travels at about 1107 FPS, therefore you can calculate it by knowing that the sonic wave travels at the speed of sound. Its all in the math! LOL. WIth all of my intakes, all of this math is calcluated, it is not just a bunch of metal thrown together, its calculated for efficiancy. Intakes are not just about FLOW.
Lots of Z cars, 1970's-1983's.
1977, Megasquirt, 12.8@ 105, 1.70 60 Foot, 2940 LBS. Blake Machine Co, Phx, AZ http://bandmzcars.com http://blakemachineprojects.com http://www.zselect.com
A:
I've never seen a Z with 16-19" intake runners. Were would you put them, I know the diesel intake they wrap around but I still don't think they are that long.
The runners on my cannon are like 6" and I get a much more broad/usable torque curve than when I run the short cannon which is maybe 2" runners but a little less top end hp.
Matt
A:
1 fast z, could you be more specific on the math you did for your intakes? I dont know that we will cover everything you are talking about and everything i will need to build mine so any knowledge you have on the subject would rock.
A:
Check out the links in my sig, and look under "intake plenum."
Pellius
Twin Turbo/N2O 73z; "fulcrum"
car info at: http://www.eng.fsu.edu/~jthagard/3liter/newengine.html
car builder info at: http://www.speedshopthagard.com/
87zxt; no mods. Well, I was thinking about a barefoot gas pedal mod.