MSP injectors size???

mx3ownzj00 said:
flow @ 36psi fuel pressure.

ok somebody explains this to me.... how can a 280cc injector flow 302cc at 36psi????? nothing for nothing, but once a 280cc injector is a 280cc injector and it wont allow to flow more then 280cc of fuel....
 
Raise the fuel pressure, you get more flow thru the injectors. I thought the stock fuel pressure was about 36? (huh)
 
LinuxRacr said:
Raise the fuel pressure, you get more flow thru the injectors. I thought the stock fuel pressure was about 36? (huh)
yep, and at WOT its around 45-48psi I believe. they are able to flow between 280-302cc max, but I wouldn't push them too far past 280cc or they'll just go static.

the numbers aren't adding up but for all practical purposes they are just 280cc injectors than can flow a lil bit more if pushed far enough. mazda(freak)
 
mx3ownzj00 said:
yep, and at WOT its around 45-48psi I believe. they are able to flow between 280-302cc max, but I wouldn't push them too far past 280cc or they'll just go static.

the numbers aren't adding up but for all practical purposes they are just 280cc injectors than can flow a lil bit more if pushed far enough. mazda(freak)

listen you cant flow more fuel than the injector size....how did you people come up with this 302cc on a 280cc injector at 36psi????you get more fuel volume not more fuel once you play with the pressure....damn.....usually the fuel at idle is like 40-44psi and rises like 2-4psi with the rpms with 4-6 being the max to compansate the demand for fuel at higher RPMs...
 
F2TNYC said:
listen you cant flow more fuel than the injector size....how did you people come up with this 302cc on a 280cc injector at 36psi????you get more fuel volume not more fuel once you play with the pressure....damn.....usually the fuel at idle is like 40-44psi and rises like 2-4psi with the rpms with 4-6 being the max to compansate the demand for fuel at higher RPMs...
well Mazda has spec'd them at 280-302cc. i'm not sure that idle fuel pressure is for sure, maybe it is in the 4x's.
 
mx3ownzj00 said:
well Mazda has spec'd them at 280-302cc. i'm not sure that idle fuel pressure is for sure, maybe it is in the 4x's.

the pressure can be correct but the size is only one....anyway i just wanted to make sure what size is it, next weekend i will be upgradinf these injectors in favor of 320cc to accomodate the raised boost..thanks for your help...
 
KyRaceFan said:
What kind of 320's are you getting?

ahhh.. i cant quite say it yet, lets just say i'm using it from a family of our cars....

BTW.. i took a look at those stock injectors today and they look awwfully small to be 280cc.... anybody found a proof that they really are 280cc???? i would love to make sure...thanks
 
F2TNYC said:
the pressure can be correct but the size is only one....anyway i just wanted to make sure what size is it, next weekend i will be upgradinf these injectors in favor of 320cc to accomodate the raised boost..thanks for your help...
Swapping the injectors for larger ones with no modification to the ECU is a little missguided. Do you have plans to do the ECU Maps as well? Here is a shot of the EIC-2, it is quite inexpensive and will add the extra fuel you need without ******* up your car with oversized injectors. Do as you like, just thought you might like to research this thing out as it's a marginal solution to your fuel problem...

SIMPLE DIGITAL SOLUTIONS EIC-2 Stand alone Extra Injector Controller!

30112003%20191.jpg
MP5T%207.jpg
 
Brian, whats the total cost for the EIC? Website?

I'm looking for something to add fuel so i can run more boost, and probably a 50 shot of nitrous.
 
positive rep left... its gonna come down to extra injectors or nitrous.

50 shot single fogger... or extra injectors and 15psi daily.. hmm.
 
KyRaceFan said:
positive rep left... its gonna come down to extra injectors or nitrous.

50 shot single fogger... or extra injectors and 15psi daily.. hmm.
Please consider doing your internals if you are planning to run over 10Psi. On Page 156 of Maximum Boost there is a chart that has Boost Vs. Compression over Octaine... Although you can use 15 Psi on this engine in it's stock form, you will need to run 115 Octaine all the time and even with that, I doubt that your SMIC will be able to handle the "Paint Stripper" that your T-25 will become.

I have reduced to 8.5:1 with froged parts. This allows for a safer margin of error. NO ENGINE ON THE PLANET CAN RUN WITH SUSTAINED DETONATION. The load on the engine goes to 1600% and the easiest path for this force is through your piston!

(boom01)​
Have a look at the attachment... I'm not saying it can't be done, just perhaps set your scope a little lower, like 11 Psi running a FMIC with Additives and ....Etc...​

BTW: Your clutch might have a hard time clamping the full force of 12.5 Psi. Again, I'm not being negative, just realistic.​
 

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Compression and octane arent the only factors in detonation.. Charge temps, plug heat range, and air fuel ratios also determine if your engine detonates.
Youve got awesome info, but thats only one piece of the puzzle.

I'd like to build the bottom end, would be great to have that peace of mind knowing my rods and pistons are strong, and wont snap... but the stock motor is strong enough for 15psi with plenty of fuel, good plugs, and low charge temps. :) I dont think detonation would be a real concern. Plus, if i did HEAR knock, id turn the boost down, and go for a better tune.
 

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