009's all done @110% Duty Cycle? (T+ tuning)

[BEATAV8]

Looks like my 009's don't like them high duty cycles much at all. They started cutting out pretty bad in the big end, missing and popping. Guess them injectors were getting a little warm??? Anyways.. Was able to tune around it by setting WOT MAF base a little leaner on the trans plus (went from 4% rich to 0%) and upping the fuel pressure. Now Inj duty cycles are around 85-90%. To compensate, the fuel pressure is up at 49-50 PSI static and she's asking for more. Will try 2% rich MAF WOT.

Shoulda bought the 50lbr's I suppose.

Anybody else have experience with 009's at high duty cycles? Seems to me after reading some of the threads here like they should hold in there a little better than 110% but maybe I'm stoned.

 

[Tom87GN]

I have 40's on my GN and experience the same deal as you do with your 009's.

My O2's are good at the start of a run, around 790, but by the big end they are all the way down in the 740's. Yuck!

I talked with a few guys who run consitently in the 9's and they say the 40's all run like that, fat on the bottom and real lean up top.

I think I need to go to the 50's as well. Bummer, until I go faster.

 

[Intercooler]

What kind of times are you guys running? 12.5@109 is okay with stock injectors. I ran 11.78 with 40's and had a little left so I sense something is wrong there.

 

[bruce]

Originally posted by MJRWOOD

Shoulda bought the 50lbr's I suppose.

Anybody else have experience with 009's at high duty cycles? Seems to me after reading some of the threads here like they should hold in there a little better than 110% but maybe I'm stoned.

It happens to all injectors, just some are so bad you can feel it.

Like I been saying, it's far easier to tune back on the injectors then try to patch em up to work.

IMO, the min injector to get a car to run right is 55s, and yes it takes getting the ecm modified.

Doing cams, I/C, chips, PP, all the mods in the world, and then cutting corners on injectors just isn't the way to do it in my book.

 

[BEATAV8]

IMO, the min injector to get a car to run right is 55s, and yes it takes getting the ecm modified.

I agree. Even if I get 50's now I would still be pushing to 80% duty at rated 42 PSI pressure at the same performance level.

Anyways... good to know I'm not alone.

 

[Intercooler]

Originally posted by MJRWOOD


I agree. Even if I get 50's now I would still be pushing to 80% duty at rated 42 PSI pressure at the same performance level.

Anyways... good to know I'm not alone.

Going 12.50's is stock injector territory. I am

 

[BEATAV8]

What kind of times are you guys running? 12.5@109 is okay with stock injectors. I ran 11.78 with 40's and had a little left so I sense something is wrong there.

Have 2 cars..
the one with the 009's is the "fast" one. Looking for 11.9x's, been running low twelves but never without problems (ie running out of injector, fuel pressure). Probably just trying to do it differently than you are. I'm only running 100 octane, so timing is not too agressive, and 60 fts have been lackluster (1.80's) due to stock rear brakes. If it were perfect out of the box I wouldn't have anything to do!

I've also run my stock injector car to nearly the same performance level a few times (mid twelves), I just can't leave it tuned that way (with 65 PSI fuel pressure and leaded 110). I always bring it back to running 13.50's on pump gas and 14-15 PSI.

 

[Tom87GN]

I never said I was an expert on racing a TR by far, so I would be open to any suggestions at what is lacking with my fuel system here.

Intercooler, if you think I should be running much faster with 40's, what do you think I should be looking for as far as fueling problems? I have a 307 pump in the tank and a billet adjustable fuel pressure regulator.

 

[bruce]

Originally posted by Intercooler
Going 12.50's is stock injector territory. I am

For how long?.
What damage will you find when you do a tear down.
Ya lots of folks like to Hammer on a tune, but why?.
Long term it'll just cost you money, and parts.

Mine has the manners of stocker, better mileage, and a real mild tune. I'm running 22d timing, 22 PSI, and on 87 Octane can't get the motor to detonate. Been on 4. 500 mile (each way) trips so far this year, and broken 30 MPG several times.

With even 40s I was dancing around to get the tune close.
BTDT, I take 55s thank you.
YMMV

 

[azgn]

many folks (including me) have gone high 11's with Blue Tops (36 lbers) and turbo like a TA-49(on race gas)......like Bruce says, there are no downsides to running bigger injectors now that the chips are commonly available

 

[Intercooler]

Tom87GN,

It is real hard to tell what could be wrong. The FP should be enough. The injector should be enough. What chip? Are you sure your fuel filter is in good shape and none of your lines have been kinked? Fuel sock is relatively new and new style non-collapsing?


Bruce,

BTDT! I have had from stock to 83's in my car. It is always better to have more fuel pump, injector, etc.. than needed to be safe and give a margin. At 12.50 though I don't think a modded ECM and 55's is called for. If you can't do that with 40's or blue tops something is wrong plain and simple! Dumping big injectors into the mix isn't the answer. Emissions is always another concern when running large >50 lb. injectors even though some have made it through. I still don't see a time for your car so I can't comment on your accomplishments.

If you can't tune it, throw a Fel-Pro at it with some 160's

 

[TurboBob]

What chip are you running?

If an Extender, make sure the switch3 is off, if a conventional chip, turn switch 3 on.

Do you run Direct Scan or other datalogging tool?

TB

 

[REDS HOT AIR]

et dont mean shlt so what kinda mph are you running ...

i just had the same problem with 50's but i was going thru at 127 mph which is the limit for 50's in a full weight car.

my buddy's car was running 116 trap speed on 009's and not leaning out with a full weight car so if your not getting atleast 116 then your not out of injector ...maybe fuel pressure in high gear but shouldnt be injector

 

[TurboJim]

Something aint right. 12.50's with 009's at 100%? Someone didnt sest their car up right. 12.50's would need 42's at 70%. Somethings amiss there. 100% SHOULD be enuf fuel for 11.3.11.4 math wise anyway.

 

[BEATAV8]

et dont mean shlt so what kinda mph are you running ...

True.... true....
Red's right. Do not pay so much attention to ET's people. Slow 60 ft's and missing/popping at the top of 3rd gear tend to make for crappy ET's. If a car can go low 12's running like a turd then the better ET's are in there somewhere.

Anyways, haven't bothered going back to the track with it until I can get it to pull smoothly thru the top of 3rd gear and into 4th with some decent O2's. She leans out gradually all the way through 3rd (from 820 to 770's) and then pop.. pop... shift into 4th.... pop and then smooth again well into 4th gear (115 MPH+) albeit with a less than respectable 760's O2's. Direct scan data shows that the lean misses occurr only when the duty cycle exceeds 100% by a good margin (ie near the top of 3rd). Seeing ~1 degree knock retard near leanest spots.

I'll have to put the external FP gauge back on and doublecheck it. Last week I upgraded from a hotwired 307 to a hotwired 340 pump and installed a new fuel filter and it did nothing to correct the problem. Something is keeping me from getting enough fuel into the damn thing.

Turbobob..
it's an extender chip... switch 3 is off

Tried 2% rich WOT last night and she decided to lean pop again. Injector duty cycle reached 104%.

 

[REDS HOT AIR]

your pop in the intake or exaust?

i had 02's in the low 600's

 

[BEATAV8]

intake

 

[REDS HOT AIR]

just checking..lean= intake pop rich= exaust pop

your definatly lean

 

[Tom87GN]

It sounds like my car runs the same as MJRWOOD's ride does. I believe everybody when they say that with 40's and a 307 I should be going faster. Now I just have to find out why.

INTERCOOLER, my chip is from Joe Lubrant, 26 degrees. My fuel filter only has about 3 tank fulls of gas / race gas through it. My sock is a newer non-collapsable style that came with the 307.

Should MJRWOOD and I be looking for kinked fuel lines????

 

[bruce]

Originally posted by Intercooler
BTDT! I have had from stock to 83's in my car. It is always better to have more fuel pump, injector, etc.. than needed to be safe and give a margin. At 12.50 though I don't think a modded ECM and 55's is called for. If you can't do that with 40's or blue tops something is wrong plain and simple! Dumping big injectors into the mix isn't the answer. Emissions is always another concern when running large >50 lb. injectors even though some have made it through. I still don't see a time for your car so I can't comment on your accomplishments.

I'm not one to play the 1/4 mile game.
But, I'm running, a 60, 55#/hr injectors, at 90-95% DC at 22d at 24 PSI. Plus I run a 90% wastegate offset in 3rd, and 85% in fourth. All on pump gas, have broken 30 MPG several times, and have better drivibility then any stocker.

Emission problems, are exactly that, and most often related to tune up problems. Car Ijames posted about passing, running 72s.

If you want to run you injectors static, high fuel pressures, fine.
You'll also have a finicky setup, and be always subject to replacing headgaskets. Lots of folks around here rely on the knock sensor and stock O2 as indicators of doom, and while they are OK for a stock motor, they're not designed for an engine making 2x the HP of the oem design.

Yep, I did pop a set of gaskets when I was trying to find the limit of my tune, was at 28 PSI, on 93. I've been running 24-26 PSI on pump gas for about a year and half now.