Injector/Fuel map info

BoostedBlood · 06-19-2009, 07:20 PM

ok so for fun i decided to run the factory 365cc injectors on my F.A.S.T aftermarket standalone. i was surprized how over sized the factory injectors were and thought i would share. the F.A.S.T ecu uses a MAP sensor verses the MAF which Toyota had went with, so i do understand that it may be slightly more efficient and may be the reason toyota used such big injectors but that is just speculation. any who, here is the shots i took after i roughed out a map that would run a 12.5 A/F under WOT ( i know its a very chopy map lol ). ok heres how the numbers work, 0 is 0 fuel and max duty is 150, the highlighted area ( whiteboxes ) are the un used boxes which are 158 kpa ( about 9 PSI ) and above. From the pics you can see that at 8PSI the injectors are not working hard at all to keep plenty of fuel to the engine. I had been runing 14PSI on 440cc RC injectors and now i begining to think that was a little over kill. Something i learned from my h22a turbo project is that matching injectors to what you need will give you more power and better power curve than runing overkill injectors. with all that being said... it is my guess that one could run stock injectors (with aftermarket fuel management) and support more boost that most would think.
http://i587.photobucket.com/albums/s...ASTfuelmap.jpg

Jackstand Queen · 06-19-2009, 09:55 PM

I'd have to agree with you on not over doing the injector size. By some quirk, I have 58 PSI fuel pressure, and with 440cc Supra injectors the engine would barely run.

With oem 365's installed, I get really good gas mileage (over 30 MPG) and good high RPM performance too. On a good day, I get 12 PSI.

328FTW · 06-20-2009, 08:40 AM

They are pretty big injectors on the 4agze. To give you some idea the factory injectors are 365cc right? The 2L JDM gen 2 3sge putting down ~170horsepower has 295cc injectors (n/a but still). Huge injectors are not as big a problem as utilizing them correctly, it takes some good tricks with pulse duration and such to make a big injector work. You have to watch your duty cycles as well. If your at 95% duty you may want bigger injectors so as to give yourself a safety margin.

Capt.Evergreen · 06-24-2009, 04:11 PM

So did u change to MAP or what... I'm persueing the samethimg... And I. Guess g F.A.S.T is a company????
Capt. EverGreen

d962r · 06-25-2009, 11:33 AM

What cams are you running?

d962r · 06-25-2009, 11:50 AM

i was compairing your map to mine. I need to figure out how to pring it out or get a pic. anyway... I see that @ 4000 rpm and 158 kpa your at 55% VE I'm at 100% or there 'bouts. how much boost are you running? and what plugs are you running? what heat range?

BoostedBlood · 06-26-2009, 04:35 PM

ok to awnser some questions, F.A.S.T stands for fuel air spark tech, they make a aftermarket standalone ecm for gm vehicles, they use all gm sensors and a wideband o2. My FAST ecm was moded from the factory to be used in a honda lol. So what i did was use all gm sensors (as done in the honda kit) and honda injectors and fitted it to my 4agze. I was runing 14PSI on 440cc RC injectors till i cloged them up, so i removed my overdrive SC pulley,installed a stock levin one and went back to the factory injectors just so i could get some use out of my car(was bothering me just siting there in shop takeing up space lol) when i was maping out a baseline fuel map i noticed the low dutycycles and found it very intriguing and thought i would share with every one

im now runing the stock boost of 9.5 PSI on stock cams with factory recomended heatrange ngk plugs. I been out of town lately and havent had a chance to reply ( sorry ) and work on my car. im going to try to get some final tuning done this weekend and hopefully get my car back on the road, will post a updated fuel map once i get one together. The last map was a very rough one and VE probably incorrect in low rpms, i did one pull just to check my AFR and it was holding 12.5 @ 4500+ 2nd-4th

06-19-2009, 07:20 PM	#1 (permalink)
BoostedBlood No Skills Join Date: Jun 2009 Location: Washington USA Posts: 20 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	Injector/Fuel map info ok so for fun i decided to run the factory 365cc injectors on my F.A.S.T aftermarket standalone. i was surprized how over sized the factory injectors were and thought i would share. the F.A.S.T ecu uses a MAP sensor verses the MAF which Toyota had went with, so i do understand that it may be slightly more efficient and may be the reason toyota used such big injectors but that is just speculation. any who, here is the shots i took after i roughed out a map that would run a 12.5 A/F under WOT ( i know its a very chopy map lol ). ok heres how the numbers work, 0 is 0 fuel and max duty is 150, the highlighted area ( whiteboxes ) are the un used boxes which are 158 kpa ( about 9 PSI ) and above. From the pics you can see that at 8PSI the injectors are not working hard at all to keep plenty of fuel to the engine. I had been runing 14PSI on 440cc RC injectors and now i begining to think that was a little over kill. Something i learned from my h22a turbo project is that matching injectors to what you need will give you more power and better power curve than runing overkill injectors. with all that being said... it is my guess that one could run stock injectors (with aftermarket fuel management) and support more boost that most would think. http://i587.photobucket.com/albums/s...ASTfuelmap.jpg

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06-19-2009, 09:55 PM	#2 (permalink)
Jackstand Queen Cage Fighter Join Date: May 2008 Posts: 677 Thanks: 52 Thanked 56 Times in 53 Posts iTrader Rating: (1/100% )	I'd have to agree with you on not over doing the injector size. By some quirk, I have 58 PSI fuel pressure, and with 440cc Supra injectors the engine would barely run. With oem 365's installed, I get really good gas mileage (over 30 MPG) and good high RPM performance too. On a good day, I get 12 PSI.

06-20-2009, 08:40 AM	#3 (permalink)
328FTW Can you say grippy? Join Date: Aug 2008 Location: New Zealand Posts: 1,513 Thanks: 12 Thanked 99 Times in 83 Posts My Google Map iTrader Rating: (0/0% )	They are pretty big injectors on the 4agze. To give you some idea the factory injectors are 365cc right? The 2L JDM gen 2 3sge putting down ~170horsepower has 295cc injectors (n/a but still). Huge injectors are not as big a problem as utilizing them correctly, it takes some good tricks with pulse duration and such to make a big injector work. You have to watch your duty cycles as well. If your at 95% duty you may want bigger injectors so as to give yourself a safety margin.

06-24-2009, 04:11 PM	#4 (permalink)
Capt.Evergreen Cage Fighter Join Date: Apr 2008 Posts: 102 Thanks: 2 Thanked 1 Time in 1 Post iTrader Rating: (0/0% )	So did u change to MAP or what... I'm persueing the samethimg... And I. Guess g F.A.S.T is a company???? Capt. EverGreen

06-25-2009, 11:33 AM	#5 (permalink)
d962r yeah I race Join Date: Oct 2005 Location: Clackamas Oregon Posts: 528 Thanks: 4 Thanked 5 Times in 5 Posts My Google Map iTrader Rating: (0/0% )	What cams are you running?

06-25-2009, 11:50 AM	#6 (permalink)
d962r yeah I race Join Date: Oct 2005 Location: Clackamas Oregon Posts: 528 Thanks: 4 Thanked 5 Times in 5 Posts My Google Map iTrader Rating: (0/0% )	i was compairing your map to mine. I need to figure out how to pring it out or get a pic. anyway... I see that @ 4000 rpm and 158 kpa your at 55% VE I'm at 100% or there 'bouts. how much boost are you running? and what plugs are you running? what heat range?

06-26-2009, 04:35 PM	#7 (permalink)
BoostedBlood No Skills Join Date: Jun 2009 Location: Washington USA Posts: 20 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	ok to awnser some questions, F.A.S.T stands for fuel air spark tech, they make a aftermarket standalone ecm for gm vehicles, they use all gm sensors and a wideband o2. My FAST ecm was moded from the factory to be used in a honda lol. So what i did was use all gm sensors (as done in the honda kit) and honda injectors and fitted it to my 4agze. I was runing 14PSI on 440cc RC injectors till i cloged them up, so i removed my overdrive SC pulley,installed a stock levin one and went back to the factory injectors just so i could get some use out of my car(was bothering me just siting there in shop takeing up space lol) when i was maping out a baseline fuel map i noticed the low dutycycles and found it very intriguing and thought i would share with every one im now runing the stock boost of 9.5 PSI on stock cams with factory recomended heatrange ngk plugs. I been out of town lately and havent had a chance to reply ( sorry ) and work on my car. im going to try to get some final tuning done this weekend and hopefully get my car back on the road, will post a updated fuel map once i get one together. The last map was a very rough one and VE probably incorrect in low rpms, i did one pull just to check my AFR and it was holding 12.5 @ 4500+ 2nd-4th