I tuned this stock b16 with just bolt ons, gsr cams, and it left me puzzled. The kid has a fuel rail and regulator, some dc headers and cai, he know the deal so he told me the dizzy was on timing before he broad me the car so i didn't even bother, just installed my o2 and kept it moving. As i start tuning on a stock p30 map, i started taking fuel out since the car was around 11.3. by the time i leaned the car out to 12.8 (i usually go for 13.1 and then + or - to see what it likes) the car was polling like crazy. I got a set of home made electronic det cans and started pushing the timing to about 30.75* final. The car pulls so damn hard for a stock b16 with basic bolt ons, he spanked GSR and b16 efs all night long by 2 cars, and this is on a full interior 99 SI coupe. I was amazed my self...

So he left the car on my driveway the other day with the car low on gas, as he was leaving the car wasn't starting so i take a peek at his pressure gauge to see if it is gas, and the gauge didn't even climb. After he put gas on the car i took a peek at the gauge and it reeds 56 psi. so i started thinking about fuel atomization and what not, this is the only explanation that can come to my mind. I mostly do street tunes and rent dynos here and there so i don't have the R&D time to figure this out. I want more experience tuners to give their opinion

 

Depends on the injector. Although, no expert on this either, but I would believe that to a point that every injector will increase atomization with higher fuel pressure until a design flaw( ie: nozzle design) gets in the way. If these were stock injectors, its possible, but probably not.

 

just because I was curious when I read this... 38-46 is stock pressure.

RDX injectors are supposed to have a far superior spray pattern for atomization compared to the normal honda injector design, and from what I've heard they result in 2-5hp for N/A engines. Not enough to result in the freak behavior that you mention.

my guess is the car has more mods than he's letting on, or more than he knows.

Then again maybe it's simply one of those freak engines where the tolerances in parts line up perfectly and the thing runs better than it should.

 

Well the motor never been opened before, his uncle bought the car back in 2000. Freak of an engine is the only explanation i could think of, that car is causing major drama on my area. People are speculating that i did a better job on his cars since i know him, than on other costumers. I give my 100% all the time...

 

The more pressure, the merrier. Until you run out of A. injector driver, or B. fuel pump.

A: Injector drivers are good till about 100 - 130 psi, depending on the ECU and injectors being used
B: Fuel pump (Walbro 255 in-tank) is good till about 70 psi.

run a Bosch 044 if you want to push the fuel pressure envelope...

 

for what it's worth I tuned the other side of the coin a while back. Couldn't get the car to make decent power no matter what we tried. Guy had the car since new and it was always slower than other SIs.