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Discussion Starter · #1 ·
I have the 4 injectors back that was original in the car from FIC and the other 6 that I had locally.
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Results of the 6 and 4 respectively for easy viewing:
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Two options I'm looking at is running the 4 that are rated at 358 or the 4 higher values with 364 installed on cylinder 4 and 361 installed at either cylinder 1 or 3, leaning more toward cylinder 3 but I'm also debating on putting the highest one on the cylinder that will have the o2 on it and figuring it out from there.

These numbers are all minor respectively but its that nit picking that has me going, inputs...
 

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Thats a cool test. I would think to run all 358. Not sure if the O2 will jump alittle more with highs and lows rated injectors but that might be a negligible difference.
 

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Discussion Starter · #4 ·
I'm going to run the 358s, was going to do offset to adjust for heat/temp differences between the cylinders knowing that 3 & 4 are the hottest but I'll save the experiment for later if I feel like it. I'll post the rest of them for sale later.
 

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Thats reasonable reasoning but I still think its too small of a difference to tell even for an O2 to matter. Just gotta live with the QR25 life's up and downs af far as heat. I never knew that about #s 3 and 4 tho. Clutch heat absorbtion?
 

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Discussion Starter · #6 ·
Look at the head gasket failure, mostly from heat and the coolant wouldn't be as cool as cylinder 1 & 2 comparatively, thermostat/water control is right there at cylinder 4 and the last to get "fresh" coolant. Its minimal but its there.

Looking at the fueling and ignition of each cylinder on my bike, its value differences are small but it accounts for intake and temp as well with 2 & 3 in the center while 1 & 4 are outside "sharing" heat on one side.
 

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I understand that. A little bit can go a long way over time
 

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They flow more like 384cc at 51 psi. That's the operating pressure of the stock fuel system. The issue with 1 and 2 also has a bit to do with cylinder balance with the intake manifold as well as where the inlet is to the fuel rail. 1 and 2 last to get fuel but that's only part of why 1 and 2 will run the leanest. That's one of the advantages of the B16 specv having 2 sets of upstream wideband sensors. You can see in the data log where they start to go lean around 6600 rpm typically. Before that they are actually a touch richer then catch up and swap. The b16specv intake manifold has that short neck and it's entry at a 90 degree angle right at cylinder 4. As the rpm gets to the top of the band air flows right past them and to the back and into 1 and 2 easily. It doesn't like to make that turn at high rpm. That's why the Altima manifold has that backwards angle to direct it against the front plenum wall. The rogue manifold has the best cylinder balance with its twisted plenum that is more of bulb shape and of slightly larger volume.
 
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