Best bet is what im looking to do i just pm'd a guy running the EVO maf and 550s and a 16G hes running 16psi and pulls strong. I want mine for a nice street daily driver and when i wanna have a little fun i can. hope that helps but 15 psi on a 14b that doesn't sound like it'd be starving for fuel to much. Thats my opinion though.

crusada said:

Best bet is what im looking to do i just pm'd a guy running the EVO maf and 550s and a 16G hes running 16psi and pulls strong. I want mine for a nice street daily driver and when i wanna have a little fun i can. hope that helps but 15 psi on a 14b that doesn't sound like it'd be starving for fuel to much. Thats my opinion though.

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Yea the evo setup is awesome and yea thanks.

Widebands say alot........... You should get one installed before you go any further.

If you know about the hp you will be making I would use a Fuel Injection Cal to figure out what injector size you want.
Some items you might not know on the calculator

Brake specific should be .63
Max Duty Cycle should be at 80% but if you do 85% that could get you by.
Fuel Pressure is usually 43.5 but you should know what fuel pressure your running.

RC Fuel Injection

I'm aiming for 250-300hp and i have a wideband I'm gunna get evo 560cc, evo maf, and 16g.

kinda wondering the same thing. I'm running stock 14b with a 17lbs waste gate actuator, and I'm still running my stock injectors with no tuning device. I do have a data-logger but have not hooked it up yet. I have a GM MAF and translator to go in with some 560cc's that are sitting on my shelf at home but have not had the time yet to put them in.

Should I/we be safe as long as we aren't pushing peak boost all the time or what would be a safe boost level for stock injectors.

Get a logger and see where your %IDC is at!!!!! You have your answer. . .

I would be careful you should put those 560's in and get a evo maf. It would be alot better and get a safc.

with the GM MAS and translator it flows like 200% better then the evo and i can tune fuel trims with the translator, Base lines and RPM ranges. and i can run it blow throw.

icepikbiker said:

with the GM MAS and translator it flows like 200% better then the evo and i can tune fuel trims with the translator, Base lines and RPM ranges. and i can run it blow throw.

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If you're pushing 60lb/min airflow, you may see a small gain. . . less pressure drop in the intake pipe. Otherwise, I think you're saying that because you heard it . Is there any evidence to back that claim?

Yes you do get to do a basic tune with the MAFT. But an evo maf and safc setup and you get a much higher resolution tune for a much cleaner curve. as well, the gm maf has been known to drop counts at very inopportune moments during a pull. At appreciable power levels, it would be prudent to look at your maf curve and see if there are any "blips", then you will need something like ecmlink to clamp the maf at a point just below that, which would then put you in a pseudo-speeddensity mode. . . The MAFT can be tricky due to it's nuances.

It is ultimately your choice, but the one reason I highlighted in your above reply is not a proven benefit. And what the poster said for an alternative to your combo allows an even finer resolution tune with no gm maf hickups; so there's no benefit with the maft's tuning ability. All that's left is the potential to hear the "whhhhooooosh". The evo maf and safc combo is worth looking at since nothing is installed and tuned yet.

You need to log your maf flow and your percent injector duty cycle (%IDC). You cannot get an answer about safety without looking at what's happening. You may be at over 100%IDC and running lean but not show issue with ambient temps at 75*F one day. Then, on an 89*F day at a slightly lower altitude, blow a headgasket or crack a piston ringland and get stranded. If you know your injector flow, then you will know how close you are cutting it at 17psi with a stock fuel system. . .

And I will tell you this, the 14b has more flow potential than how much air the stock 1g maf can meter. I've pushed the 14b beyond how much the 1g maf can meter myself. You can overrun your 1g maf (flow more air than it can meter) at about 30lb/min; give or take a lb/min or two correcting for the ambient temperature. I know the scanmaster and tunerstein and typical loggers for the 1g don't log more than 1600hz. The maf overruns at 2100hz. This is a VOLUME flow amount BELOW the 14b compressor map by about 13%. At this point the maf will begin to skip, or drop hertz counts. The drop in the hertz number tells the ecu that there is LESS airflow moving into the engine, when that is not the case. Extreme lean conditions occur. And in my case, my $250 scanmaster logging tool won't ever tell me how close I am at that 2100hz level. It stops logging hertz 30% BELOW that level. It's always best to upgrade to a maf you KNOW will beable to read all the airflow potential that may come into the engine; like when you up the boost past 1600hz volume flow. Upgrade mafs: 2g maf, MAFT, or 3g/evo maf. All you need is a 2g maf. They typically cost less than a gm maf.

In all likelyhood, you will trigger fuel cut. Besides picking your teeth out of the steering wheel, the act of fuel cut is also an extreme lean condition in the combustion chamber. Do it enough and you're headed for a blown head gasket. Fuel cut is the ecu's last ditch effort to contain runaway boost. Don't purposefully run around in that range. That is why you should wait until you become motivated enough to install a logger. Close to 100%IDC will mean that fuel cut is around the corner.

I still don't know why you would wonder about running almost twice the boost without a logger, though you have one right there that you just havn't installed yet. . .

you are right that is what I had read (either off here or another car forum), and read that they were flow tested. I have never seen the flow charts or any hard evidence of their claims, so I just ASS-U-MEed it was true.

I was unaware that the evo mas was better then the GM set up. My big reason for going with the GM was i got it for cheap I got the set up for less then $100 if i remember right.

I have been slacking on getting it put in my car, my apartments dont allow working on cars in the parking lot. lame-o's.

I do have it set up for 17lbs but i have never even got past 10~12lbs. I normally run less the 7lbs for those 30 sec. street launches, because I dont really know whats going on with my car (not logging). Once I get my logger in and see how my day to day runs look maybe ill get into tuning.

Thanks you for the info though, I like the ricer WHOOOOOSH . makes me feel special.

volcomsnow245 said:

Hey guys I didn't find a concrete answer so I'm just going to make sure. Well I have a 14b running 15psi and I still have 450cc injectors but I do have a walbro fuel pump so am I starving my engine for fuel or is it ok. I also have a safc and tried adding fuel but don't want to go lean. This is just until december when santa brings me my 16g, 560cc, and evo maf .

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What a HUGE thread and LONG arguements to say....


no.


You can run it at 16 psi safely. Heck I ran mine to 19 psi on just a 255.

You don't know the answer any more than the op or anyone else here without looking at the op's wideband. . . The answer is purely in that single piece of logging equipment. THAT is the answer. A side is this: it's silly not to get a logger. He has a 1g that is easy to log knock.

Your setup may not have blown up at 19psi. But you don't know what the identical setup will do with different ambient conditions. You need to log what is being demanded from the fuel system. It WILL vary, even on identical setups.