what size injectors to use with evo3 16g?

[noreaga0221]

Local guy does 11.0x's on a 20g. Injector size? 550's.

http://www.philadelphiadsm.com/forum/profile.php?mode=viewprofile&u=83

 

[ShapeGSX]

Local guy does 11.0x's on a 20g. Injector size? 550's.

http://www.philadelphiadsm.com/forum/profile.php?mode=viewprofile&u=83

The race gas he is running is saving his engine, either that or he has a 1500lb car.

I maxed out my 550s at around 113mph in the 1/4. I did run 118mph on them, but I basically lost all control over the fueling since they were maxed out. They were delivering 550cc/min for most of the drag run, even though the ECU wanted to put in more fuel to stay at 12.0:1 A:F. The ECU wanted 104% IDC out of them, and the poor ECU isn't the master of time and space, so it couldn't get it done.

The 660s are at a much more comfortable 84% at the same A:F ratio.

So yeah, 122mph is probably doable with 550s, but the A:F ratio is really creeping up there. Probably in the 13.5:1 range. Way too lean to be safe, IMO. I bet he could make even more power if he upgraded his injectors and tuned the fuel correctly instead of just running the injectors wide open all the time.

Just because it has been done doesn't mean it is smart to do. For example, millions of people still use AOL.

 

[badgsx]

So from what Im reading about 660's being hard to control with a safc, does that mean that a safc should really only be used with 550's?

 

[jackalopeTsi]

im getting an evo3 next week and will be getting injectors eventually, it sounds like youd be able to get more out of that turbo with the 660s, but its harder to tune with the safc, what about the GMAF-Translator. i will be going that route this winter.

 

[ldstang50]

my buddy has a 2g awd, 550s, evo 16g ported, ported O2, 2.5dp, thermal car back, injen intake, sbr fmic, dsmlink. he is at 120%duty cycle with the 550s at 22psi. He is upgrading to 780s with an fpr. His car was actually getting knock with the 550s although he was running a 11.4a/f. fresh sparkplugs properly gapped and brand new oil. he was just over working his injectors.
the 550s can work. But the bigger injectors allow you to run safer

 

[sweet97]

780's!! 720's are toobig for my 50 trim. 780's with a 16g will be a mistake. 660's will cover from a 14B to a 50 trim.I use the MAF-T. Duty cycle is too low with big injectors causing high timing. Mark

 

[ldstang50]

yes 780s. they are FMC?????? i believe. If i'm correct they are called 720s but the flow rate on them he said is 780
I have 700cc in my car, with no tuning i was richer than bill gates. Now i got them tuned and they are purty. Cant' wait for my BR580 next season.

 

[Tarantula]

I have an EvoIII and still on stock fuel setup. I am in the market of getting fuel injectors to be able to turn up the boost from 15 psi. (28.5 lbs/min airflow) With my stock injectors I have to have my SAFC-2 at +3 from 5000 up because my timing would drop alot. My timing flatlines with +3. Knowing that my injectors are pretty much open all the time, I don't floor it much. I want to upgrade (Long over due!!) and was reading on how 650 is difficult. Well does anyone have opinions on the Hahn's 625CC injectors??? I thought this would put me in a safe place for tuning. Its more than 550's and less than 650'd so that would mean more safety with IDC over 550 and more adjustability over 650.

What you guys think. I wanted to be sure before buying the 625's. I pretty much won't be going bigger on the turbo. I would be happy with 350-380 solid HP to the AWD.
Heres the link to the injectors...
http://www.hahnracecraft.com/hahn/parts/fuel.htm

 

[Stoner]

my buddy has a 2g awd, 550s, evo 16g ported, ported O2, 2.5dp, thermal car back, injen intake, sbr fmic, dsmlink. he is at 120%duty cycle with the 550s at 22psi. He is upgrading to 780s with an fpr. His car was actually getting knock with the 550s although he was running a 11.4a/f. fresh sparkplugs properly gapped and brand new oil. he was just over working his injectors.
the 550s can work. But the bigger injectors allow you to run safer

I agree with this and everyone else that has said to go with the 660's or bigger. With the dsmlink you can idle like stock with any size injectors because you calculate the global setting and the dead time.

I have a evo3b16g with 550's and dsmlink, I was running 16-17psi of boost and seeing upper 80% IDC. I am getting a fmic and turning up the boost soon and I am sure I will be maxing them out. I wish that I would have listened to everyone when they told me to go bigger, because now I have to.

 

[ucancallmedebo]

I have 550's with the evo 16 with everything ported with 2.5 inch exhaust and cams. Also I got the bottom to top flow road race front mount. My boost spikes to 20 and stays at 15. This morning at about 35deg my duty cycle was 110% at 6800 rpm. My AFC is zeroed out with jeffs chip. I logged about 2000 htz. 550's are crap on pump 93oct. 750's and new chip are in the mail .Does this duty cycle at 2000htz sound high? Maybe I am to rich and maxing my injectors though. It should be real close with the chip and the afc zeroed out though. I dont have a wideband yet. After the new injectors I will be shootin more gas than a trip to taco bell.

 

[rowlex]

do 650's or a little more. Im running the evoIII with all support mods and FIC 650's, I've hit 72% duty cycle at ~13-14 psi. Tuning with DSMLink, very little knock.

 

[Steve93Talon]

The race gas he is running is saving his engine, either that or he has a 1500lb car.

The car ran just fine on pump gas - and it trapped the same on 103 unleaded as it did on C16. It weighs 2925 with driver. We just swapped in 780s and a keydiver chip, we'll see if it picks up any power.

 

[daren_p]

I have an EvoIII and still on stock fuel setup. I am in the market of getting fuel injectors to be able to turn up the boost from 15 psi. (28.5 lbs/min airflow) With my stock injectors I have to have my SAFC-2 at +3 from 5000 up because my timing would drop alot. My timing flatlines with +3. Knowing that my injectors are pretty much open all the time, I don't floor it much. I want to upgrade (Long over due!!) and was reading on how 650 is difficult. Well does anyone have opinions on the Hahn's 625CC injectors??? I thought this would put me in a safe place for tuning. Its more than 550's and less than 650'd so that would mean more safety with IDC over 550 and more adjustability over 650.

What you guys think. I wanted to be sure before buying the 625's. I pretty much won't be going bigger on the turbo. I would be happy with 350-380 solid HP to the AWD.
Heres the link to the injectors...
http://www.hahnracecraft.com/hahn/parts/fuel.htm

The HRC 625's don't actually flow 625cc, I know this because I have a brand new set that I had flow tested. They flow more like 580-590cc. According to the guy that tested my injectors its common for them to flow not as much as the manufacturer states since their tests are in ideal conditions & some test at higher then the standard 43 psi. The HRC's are still a good buy because they still offer more flow then the 550's. I've got the EVOIII & I will be running 750's but I have dsmlink so I can control them just like stock & I wont have to upgrade in the future when I get a larger turbo. I've heard from alot of guys that they can control the 650's/680's with their safc no problem. I would think you would get too much timing from this since you have to put in such a large -ve correction factor, but I have no personal experience with the safc so don't take my word for it

 

[RavenX]

Hmm thats weird at 20psi i was at 75% on the Evo16g on pump gas. But anyway i would also recommend 650's at least for the evo. I got myself a vtrim now and i am putting in 850's since i plan to run 30psi with race gas so i need all the safe margin i can get

 

[Bino]

Are there any blaringly obvious reasons why I never hear about people raising the fuel pressure? A lot of people seem to highly recommend running an AFPR, but I've never read a thread where people discussed actually adjusting them. If you had 550's at 43psi and raised the fuel pressure to say 55psi, on paper you're running about a 700cc injector. Granted, this doesn't take into account any of the losses in the system, which would also increase with the pressure increase. It's just an off the 'cuff ratio calc, but you'd at least be running a 680 or so.

Just a thought for the guys that already have 550's and are already planning on picking up an AFPR.

 

[sweet97]

You're right, the AFPR is a great tuning aid. Surprisingly you would not believe the number of guys who think all it does is bring the base pressure back under control with a big fuel pump! I use the MAF Translator and if I back off on full throttl setting I get more timing due to the ECU thinking I am just cruising. Adding to the base gives some extra fuel under that WOT scenario which can prevent knock from the additional timing. It can also make an injector act like a larger injector. I believe most injectors are rated at 43 psi so setting the base higher will produce more flow. Mark

 

[ShapeGSX]

You tax your fuel system a lot more at high pressures. It also gets harder to dial in the idle. Remember that if you raise the base pressure to 55psi, the fuel pump has to fight 80psi at just 25psi of boost.

 

[Tarantula]

Well I listened to what everyone said and put in FIC's 650. At idle I have to dial in -11 to keep it perfect, and -19 across for the low throttle settings. For High, To get .92-.94V I have to dial in -43 I think I have FPR overun (Even though I have the Walbro 190 rewired) cause most of the time my -19 is not enough to keep it from running rich. Still waiting on the AFPR to see what I can get. For now I know that its rich all over the place. I clean the muffler tips and do a few miles of driving with occasional WOT and next day look at my tips and they are covered with heavy soot.

 

[97gstnick]

you know... you could just get 550s or 660s and what ever deficiency you have in fuel, substitute it with methanol injection....(higher octane ) i plan on buying 660 for my rs49t and running 20 psi, low duty cycle with methanol injection. (just need to do my math and calculate how much methanol i need....)

 

[killab443]

There is a site that gives you the exact setup for SAFC with 660's I will have to find it!

Hey do you have that site for the afc setup on 660s.
thanks

 

[ShapeGSX]

You shouldn't be tuning by O2 sensor voltage.

 

[sweet97]

Well I listened to what everyone said and put in FIC's 650. At idle I have to dial in -11 to keep it perfect, and -19 across for the low throttle settings. For High, To get .92-.94V I have to dial in -43 I think I have FPR overun (Even though I have the Walbro 190 rewired) cause most of the time my -19 is not enough to keep it from running rich. Still waiting on the AFPR to see what I can get. For now I know that its rich all over the place. I clean the muffler tips and do a few miles of driving with occasional WOT and next day look at my tips and they are covered with heavy soot.

I ran the EVO and used 550's which were fine up to 22 psi, that's when they hit 100% IDC. The AFPR sold by www.fullthrottlespeed.com is a nice bolt on if they have 1 in stock for only $145./nice!
If anyone is not planning to go over 18 psi I would say 550's would be perfect. I even was able to use the stock sidemount IC but a small FMIC would be better like the Dejon street FMIC. It can be installed without removing the bumper. Mark

 

[ShapeGSX]

First of all, hitting 100% IDC or even over 90% IDC isn't something you want to see happen. Past 90%, the injectors are just wide open all the time, anyway. You lose all ability to actually control your fuel.

Second of all, anything you do to make your engine more efficient, like install a larger intercooler, or better IC piping, or cams, will only make the demands on the injectors even more great. Cooler, denser air means that more air makes it into the cylinder, and that air has to be matched by fuel. So just because you were "fine" with 550s with a sidemount intercooler and stock cams at 18psi (still over 90% IDC, I would guess) doesn't mean that other people will be. There are way too many variables.

 

[sweet97]

Just stating what worked for me under "X" conditions. The 22 psi was with race fuel. 660's are a great injector, even good for a 50 trim. I am seeing guys with the tO4b going with 750cc and higher but without dsmlink or a burned chip they will run to rich. I tried 720's with my 50 trim when I was told to go with 660's. Had to trade for 660's because the 720's were too big for the translator causing skyhigh timing. Of course 20 psi is enough for me and these guys going with 750's and higher must be shooting for 25 psi. mark

 

[Boiler2]

Are there any blaringly obvious reasons why I never hear about people raising the fuel pressure? A lot of people seem to highly recommend running an AFPR, but I've never read a thread where people discussed actually adjusting them. If you had 550's at 43psi and raised the fuel pressure to say 55psi, on paper you're running about a 700cc injector. Granted, this doesn't take into account any of the losses in the system, which would also increase with the pressure increase. It's just an off the 'cuff ratio calc, but you'd at least be running a 680 or so.

Just a thought for the guys that already have 550's and are already planning on picking up an AFPR.

I am glad someone finally mentioned it. This is the answer. I hear & read 660's are hard to tune with the SAFC so you can install 550's and raise the fuel pressure and still maintain the tunability and idle quality with the SAFC. I have been doing this for a year and a half now. I run my fp at 50 psi with the vac line off and I run 19 psi on 93 octane with no pulled timing. Just make sure you have no leaks (boost and fuel) and you have a fuel pump that can handle it. I use the supra pump which is good to over 80 psi (look it up) plus I rewired it. RC550's are stable consistently to 75 psi fp and can be run to 100 psi for short bursts per the manufacturer.