this is very good news...well done.

would you please post your mpg when you measure?

thanks, claude

_________________
81 fairmont, 347, c4, A9P, 75mm ProM C-42, 75mmTB, Mass-Flo EFI intake, 42# inj, CI cam, canfield 195 heads.

68 f100, 460, c6, A9L, 85mm PMAS, 1000cfm 4bbl TB, victor 460, 30# inj, lunati cam, d0ve-a heads.

It seems plausible that if it knew when the spark fired, then it could determine how many crank degrees would be necessary to pass before that cylinder exhausts into the exhaust system. I have no clue whether it is actually doing this or not. And I agree, at 4000RPMs, it would be even more of a challenge. But fortunately for the EEC, most Closed Loop conditions don't exist at 4000RPMs. Once someone gets a motor wound up that high, they are usually at WOT or are deceling from a WOT/near-WOT condition.

_________________
...Always Somethin'

89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA

Member V8-Ranger.com

Nah, just a good debate and you presnt lots of sound ideas. But I don't think you or I (or most in this forum) know the real answers seeing as Edelbrock, AFR, Twisted Wedge, Crane, CompCams, Brodix and dozens of other companies have spent millions on these theories and none of them have the perfect answers all the time either. I'll just leave it that I think little if any scavenging occurs during low and moderate street operation and when there is scavenging going on its at high RPM where the O2 sensors aren't in the equation anyway.

_________________
94 GT, CBAZA/J4J1, 347 (on a R302 block), F303 cam, Performer II Intake, 1.7 Crane RR's, 1 5/8 Shorties, 70MM BBK TB, C&L 85mm Tuner MAF, Pro-Charger D1SC, 60#'s, TKO 600. Runs 11:80's

I could agree with that.

_________________
...Always Somethin'

89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA

Member V8-Ranger.com

update ...

i am actually very surprised at how much of a difference setting the injector timing has made

my idle is now very steady at about 800. before that, it would surge and hunt like crazy, often dieing ... not only at startup, but even when warm.

and my gas mileage is much better.

bottom line ... the engine runs much better now than before

you guys with cams with big overlaps, i highly recommend looking at your injector timing values

_________________
95 GT Vert, TwEECer R/T v1.30A9
1970 block, 410ci, 10.27:1 CR, 42#, LMAF, CBAZA/T4M0, AOD, 2500 Stall, Custom Cam

1967 Fairlane Vert, 390FE, C6, 100% stock

I thought I remember reading that injector timing at idle is set to a specific value and it doesn't change. So, the injector timing tables have no affect at ildle ( at least for A9L )? Can someone set me straight on this?

Thanks,
Jeff

_________________
It's not me...

1992 5.0 LX - 363 Dart Block, AFR185, 39lb Injectors, 80mm PRO-M MAF, HTM Custom Cam, Edelbrock RPM2, GForce T5, 4.10, BBK 1 3/4, 3" VRS Catted X-Pipe, A9L, Tweecer RT, BE, EA, LM-1

There is a GUFx scalar (CINTSW) to make that happen. But I don't think that's set by default in the A9L.bin. However it is set by default in the X3Z tune. When set, this parameter controls injector timing using Injector Timing Value at Idle (MIDTV), Injector Timing Value for MFA (MINTV), or Injector Timing Value in Neutral (CINTV). I also suspect the timing defined by those 3 TV scalars is also subject to a fixed timing delay (TCINJD), but I really don't know how that scalar fits into all this. I'm not sure why you'd define a fixed timing value, then delay it. A9L and X3Z have radically different values for each of these scalars.

_________________
...Always Somethin'

89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA

Member V8-Ranger.com

'Enable Special Injector Timing at Idle' (aka CIDRSW) - Set to fix the injector timing to the 'Injector Timing Value at Idle' (aka MIDTV) value when the vehicle is in drive.

'Injector Timing Value at Idle' (aka MIDTV) - Injector timing value used when in drive and the 'Enable Special Injector Timing at Idle' (aka CIDRSW) flag is set.

'Enable Special Injector Timing in Neutral' (aka CINTSW) - Set to fix the injector timing to the 'Injector Timing Value in Neutral' (aka CINTV) value.

'Injector Timing Value in Neutral' (aka CINTV) - Injector timing value used when the 'Enable Special Injector Timing in Neutral' (aka CINTSW) flag is set providing the startup delay for fixed injector timing conditions have expired.

'Injector Timing Value for MFA' (aka MINTV) - Injector timing value used when in fuel economy mode.

'Injector Timing Time Constant' (aka TCINJD) - The time constant for the rolling average calculation of the 'Injector Delay' (aka INJDLY) value.

From what I see you are correct, the CINTSW scalar is disabled by default in the A9L.bin ( I'm using TunerPro ).

I want to make sure I understand the relationship of FN1315 - 'Injector Timing' table and the scalars mentioned above.

If I have only changed FN1315 - 'Injector Timing' table and CINTSW is not enabled, does the FN1135 table affect all injector timing? ( neutral, idle, PT, WOT )

If CINTSW is enabled, I can specify CINTV to set a different injector timing value for neutral. ( likewise - I can also enable CIDRSW and set MIDTV ). I assume for a 5 speed manual tranny car, both CINTV and MIDTV should both be set to the same values?

Thanks,
Jeff

_________________
It's not me...

1992 5.0 LX - 363 Dart Block, AFR185, 39lb Injectors, 80mm PRO-M MAF, HTM Custom Cam, Edelbrock RPM2, GForce T5, 4.10, BBK 1 3/4, 3" VRS Catted X-Pipe, A9L, Tweecer RT, BE, EA, LM-1

FN1315 is the primary source of the injector timing value unless the appropriate condition is met for one of the three fixed values to be used instead. It is used in all situations unless in fuel economy mode (aka MFA mode) or the CINTSW and/or CIDRSW parameters are enabled.

You can specify the CINTV and MIDTV parameters to any value (within reason to suit your cam).

It depends on what your 'Transmission Type' (aka TRLOAD) parameter is set to as to how the values will be used (assuming the hardware corresponds to what you have it set to).

I'm deep into fooling around with my Injector Timing again in search of a better idle and in an effort to eliminate low load bucking. Now I remember that in this forum a while ago it was concluded that with CBAZA the values in the table represented when the injector was supposed to finish, not when it is to start as tripleblackvert describes above. If this (injector finish) is true then there is no way to prevent unburned fuel from going out the exhaust at high injector duty cycles with a cam that has overlap. You could set the value to have the injector open and close while the intake valve is open and the exhaust is closed and it would work at low load/RPM, but once you start getting longer PW's and shorter timeframes due to RPM the injector is going to be spraying during overlap. Anyone agree? Or disagree? Even though I like the ruppity rupp that I attribute to the cam I'm convinced my idle could be better.

_________________
94 GT, CBAZA/J4J1, 347 (on a R302 block), F303 cam, Performer II Intake, 1.7 Crane RR's, 1 5/8 Shorties, 70MM BBK TB, C&L 85mm Tuner MAF, Pro-Charger D1SC, 60#'s, TKO 600. Runs 11:80's

The 'Injector Timing Edge' (aka INJREF) flag determines whether the rising or falling edge of the fuel pulse is used for fuel timing.

If you keep that scalar such that your numbers represent your STOP time, then you adjust that table via calculations from EA based on your datalogs. You indicate when you want the injector to begin firing in EA. EA analyzes what the average injector pulse is for all your RPM/Loads represented in your datalog, then calculates when you need to set the STOP time to get it to start when you specified.

I personally prefer defining when I want the injector to stop so that I can limit how far into the intake stroke the injector fires as you get up into the upper RPM/Loads. At the lower RPM/Loads, its no big deal. There's plenty of time to get the payload of fuel squirted and you have a good bit of leeway as to when you want that to happen. Thus starting time of the injector is more relevant at the lower RPM/Loads since adjusting when the injector starts affects idle and run quality a bit. But when you get heavy in the loads, and high in the RPMs, even a big injector is going to be firing at least 1/2 of the fuel to be delivered when the intake valve is closed. Once you got a huge pool of fuel on the valve at WOT, it doesn't really matter anymore how much is there as long as all that needs to be there is there. What becomes far more important is making sure the injector gets started squirting fuel early enough that it stops before the intake valve is closed up. If the injector is still firing when the intake valve is closed, you just cheated that intake charge of some of its fuel. Your saving grace is that you were likely perpetually doing that and the current intake air charge received fuel that was cheated from the previous intake. The catch is, during acceleration up through the torque curve, the previous air charge may have had less air than the current air charge, and thus less fuel, which means you perpetually run the mix a tad lean until you peak the torque curve and perpetually run the mix a tad rich.

So to avoid that, you let EA calculate the stop times for your injectors. For the values EA calculates that are beyond the closing point of the intake valve, you manually modify them not to exceed some fixed number. So for instance if you decide that you don't want the injector firing beyond say 550° because the intake valve is at .050" at 580°, you can manually type in 550° for any values EA calculated higher than that. And now the EEC will begin firing the injector at a time it believes will complete the fire by 550°. This gives time for most all the injected fuel to make it into the cylinder before the intake valve is completely closed.

Make sense?

_________________
...Always Somethin'

89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA

Member V8-Ranger.com

Yes, it makes sense. First of all, I wasn't paying attention. Last I read the "flag" was not available to us and I have been operating on the notion that in CBAZA it was the falling edge and you couldn't change it. Hell that was probably pre-BE era. So thanks sailorbob for straightening me out on that. Now I have more to think about and thankfully more options. Chris, I agree that the falling edge is probably still the best option, I just have to think it through. I really appreciate that you clarified the mystery of what EA is doing in its calculations. I saw the option to select rising or falling edge in the EA timing table calculator, I just didn't think I could change the EEC through TwEECer. Since I get to 85% duty cycles I want to focus on getting the fuel blown in by the time the intake is closing and is at .050" which is what you said you are doing. I can set it up so that it is squirting after exhaust is closed and the piston is moving down for intake stroke at low loads/rpms, and set it to be done at .050" intake closing on the higher loads/RPMs knowing that scavenging the cyclinder will be occuring at the high end and compensate for that.

_________________
94 GT, CBAZA/J4J1, 347 (on a R302 block), F303 cam, Performer II Intake, 1.7 Crane RR's, 1 5/8 Shorties, 70MM BBK TB, C&L 85mm Tuner MAF, Pro-Charger D1SC, 60#'s, TKO 600. Runs 11:80's

Where's the Documentation section??? Maybe I'm just blind.

_________________
stock block 347, highports, CI TLSR
C-4 8" 4500 stall, 3.90 8.8
Super victor efi intake, 03 cobra 39lb injectors
4500 Wilson TB Speed density setup with a Map-Ecu
1 3/4 kooks- 3" dumps, a9lL/Map-Ecu, Tweecer
Techedge wideband
11.19 at 120.... D.A. of 5500' (love this mountain air)

When Jon upgraded the site the documentation was not put back on. Have a look at this thread.
viewtopic.php?f=3&t=13227

_________________
94 GT, CBAZA/J4J1, 347 (on a R302 block), F303 cam, Performer II Intake, 1.7 Crane RR's, 1 5/8 Shorties, 70MM BBK TB, C&L 85mm Tuner MAF, Pro-Charger D1SC, 60#'s, TKO 600. Runs 11:80's

I've downoaded the spreadsheet and have everything entered. Its giving me 600* for all cells? I've looked over it many times and see no errors in my inputs. How do I post files? I can post my cam specs and what I've entered in the spreadsheet just don't know how.

_________________
stock block 347, highports, CI TLSR
C-4 8" 4500 stall, 3.90 8.8
Super victor efi intake, 03 cobra 39lb injectors
4500 Wilson TB Speed density setup with a Map-Ecu
1 3/4 kooks- 3" dumps, a9lL/Map-Ecu, Tweecer
Techedge wideband
11.19 at 120.... D.A. of 5500' (love this mountain air)

I think there is a screw up somewere...or 99% chance its just me lol

Under the very first post



First of all how did you get this number .0000644421779 it doesn't even match any number in here.... And when I do the math myself for a 302 ci instead of a 410 ci I get different answers obviously but some are way outa the park.
Like this one, instead of getting a pulse width close to this answer 5.53493412 ms.... I get a answer like this 40.769491654944 ms this is totally wrong, were did screw up???

This is what I got so far using a 302 and 42#er's I just wanna see how close I get to from my current tune.

302 ci / 8 cylinders = 37.75 ci per cylinder
37.75 ci x .85 VE = 32.0875 ci of air
32.0875 Air x .50 Load = 16.04375 ci
16.04375 ci / (12 x 12 x 12 = 1728) = 0.00928457
0.00928457 x .075 = 0.00069634275 lbs of air
0.00069634275 Lbs.Air / 14.64 A/F Ratio = 4.75643954 lbs of fuel, but then the decimal place gets moved.....WHY? 0.000475643954 Lbs of Fuel
42# / (60 minutes x 60 seconds x 1000 milliseconds = 3600000) = 1.16666667, and again?? 0.0000116666667
0.000475643954 Lb.Fuel / 0.0000116666667 Fuel per ms = 40.76948165494433812873 ms <---This is were I get fluffed up? Instead of a answer like this 5.53493412 ms I get this 40.76948165494433812873 ms

HELP....lol

Thanks guys
Smitty

_________________
94GT, 511RWHP,Performer Heads/1.7 CC RR,Performer RPM II's Upper/Lower(Ported),D1sc Procharger/Intercooled 3Core "10 PSI",MSD BTM, 87 Short Block/Main Girdle,70mm TB,AeroMotive Fuel system 2-255lph Walbro Pumps,TwEECer RT, CBAZA - T4M0 Cal Edit/Con or Binary Editor Tuned off J4J1.

I'm not following that math at all.

Unless you are just trying to be academic, the only reason I know of to calculate PWs is to estimate what size injectors the engine will need. But if you know what HP the engine will be, the correct Injector size is already well known. But lets assume you want to be academic. So lets start with WOT conditions. Anything less than worst case would follow the same logic, but I can't think of a reason to calculate non-WOT conditions. So if you are going to assume a naturally aspirated 410 CID V8, 70% Volumetric Eff (i.e. ~70% Load@redline), running 12:1 AFR, while using 36lb injectors. Now with these values, I think you can calculate a PW.

Get the CI/cylinder:
410CID / 8 = 51.25 CI/cyl

Get the air in the cyl assuming 70% VE:
51.25 * .70 = 35.875 CI

Convert CI to lbs of air at atmospheric pressure which is close to the pressure in the cyl at WOT...not exact, but close:
Air is 1.2 kg/Cubic Meters = 1.96645e-5 kg-air/CI = 4.3353e-5 lb-air/CI

35.875ci x 4.3353e-5 lb/ci = 0.00155528 lb/cyl

Calculate the fuel amount assuming 12:1 AFR:
0.00155528 lb-air/cyl / 12 AFR = 0.000129607 lb-fuel/cyl

If you run stock 39 PSI, then this drops them to an actual size closer to:
36 lb/hr x 39 PSI / 43.5 PSI = 32.4 lb/hr

Calculate the PW in milliseconds (ms) assuming 32.4 lb/hr@39PSI injectors:
32.4 lb/hr = 8.9655e-6 lb/ms

0.000129607 lb-fuel/cyl / 8.9655e-6 lb/ms = 14.5 ms

If you want to calculate PWs for some other Load, injector, AFR, elevation from sealevel, fuel pressure, etc, then rerun the numbers with the changes you have in mind.

BTW, if anybody else see's a flaw in my math, please point it out. Although I think this is the right way to calculate PWs.

And that's about what I'd expect for a PW for a 410 with some good mods to support that kind of airflow. Note I'm using 70% VE which is ~70%Load. 70% is not the max Load, it's the load at redline. Generally you want to calculate PW at the peak HP and max RPM just to confirm that your injectors are not undersized.

So if you wanted to convert this PW into a Duty Cycle, you need to do some further math AND you now need to assume an RPM. So lets assume you are hitting 14.5ms@6000RPMs, what's the duty cycle?

Calculate what a 100% DC time would be:
6000 RPM / 2 rev/cycle x 1 min/60sec = 50 Rev/Sec

1 / 50 rev/sec = .020 sec/rev or 20ms

14.5ms / 20ms x 100 = 72.5% Duty Cycle

Perfectly sized injectors don't exceed the 70-85% Duty Cycle range. Injectors can go higher or lower, but you should NEVER go over 90% or you start getting dangerously close to 100% and that's not good.

_________________
...Always Somethin'

89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA

Member V8-Ranger.com

wow. i haven't been on this site for a while, and just logged on and notice that there was some activity on this thread they i never responded to ... sorry

let me dust off my thoughts on this stuff and maybe you guys can correct all the places where i am confused.

_________________
95 GT Vert, TwEECer R/T v1.30A9
1970 block, 410ci, 10.27:1 CR, 42#, LMAF, CBAZA/T4M0, AOD, 2500 Stall, Custom Cam

1967 Fairlane Vert, 390FE, C6, 100% stock

So in my 95 Cobra CBAZA Strategy all the inj timing values are factory set at 300. By reducing those values to 250 would that be firing the injector sooner or later? When I enter 250 my idle AFR gets a little richer.

_________________
1995 Cobra, 331, 2.02/1.60 fully ported GT40 heads, Extrude Honed Cobra U/L, 30# injectors, Isky Cam 228/238-524/544-112º LSA w/9º overlap, headers, O/R exhaust, 65mm t/b, 73mm C&L.

1993 Lightning, 351, AKCO MAF Conversion, Vortech S-Trim, Intercooled, 60# Injectors, HPX Slot Meter, AFR Heads, HO Mustang Roller Cam, 1.6 RR's, Longtube Headers, GT40 intake, Accufab 70mm race tb, 4.56 gears, QH, BE, Innovate LC1

by default, the values in that table are the crank position when the pulse should end, so lowering the value from 300 to 250 means it should fire the injector earlier.

_________________
95 GT Vert, TwEECer R/T v1.30A9
1970 block, 410ci, 10.27:1 CR, 42#, LMAF, CBAZA/T4M0, AOD, 2500 Stall, Custom Cam

1967 Fairlane Vert, 390FE, C6, 100% stock

Chris,

I think you meant 50ms per cycle and not per rev. At 6000RPM there are 100 crank revolutions per second and as you noted 2 revolutions are required per cycle (720 degrees rotation).

_________________
94 GT, CBAZA/J4J1, 347 (on a R302 block), F303 cam, Performer II Intake, 1.7 Crane RR's, 1 5/8 Shorties, 70MM BBK TB, C&L 85mm Tuner MAF, Pro-Charger D1SC, 60#'s, TKO 600. Runs 11:80's

Will firing the injector sooner help control detonation?

_________________
1995 Cobra, 331, 2.02/1.60 fully ported GT40 heads, Extrude Honed Cobra U/L, 30# injectors, Isky Cam 228/238-524/544-112º LSA w/9º overlap, headers, O/R exhaust, 65mm t/b, 73mm C&L.

1993 Lightning, 351, AKCO MAF Conversion, Vortech S-Trim, Intercooled, 60# Injectors, HPX Slot Meter, AFR Heads, HO Mustang Roller Cam, 1.6 RR's, Longtube Headers, GT40 intake, Accufab 70mm race tb, 4.56 gears, QH, BE, Innovate LC1

There's the error. 50 cycles/sec, not 50 rev/sec. Thanks for catching that. The math was right, the units is where I got screwed up.

_________________
...Always Somethin'

89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA

Member V8-Ranger.com

DOH! Yeah, you're right. well you know what I meant anyway...

_________________
94 GT, CBAZA/J4J1, 347 (on a R302 block), F303 cam, Performer II Intake, 1.7 Crane RR's, 1 5/8 Shorties, 70MM BBK TB, C&L 85mm Tuner MAF, Pro-Charger D1SC, 60#'s, TKO 600. Runs 11:80's

all this injector timing calculation stuff, blah

i go load up the cam values in EA

then i note the cam events for the exhaust close and the intake max lift

i set everything from 40 load on down to 60 degrees after the exhaust closes
and i set everything from there on up to 20 degrees before the intake's max lift

for example:
on an f303 installed straight up with 1.6 rockers, i set everything from 40 load and down to 414 and everything above 40 load to 449

good enough for 1200rwhp

There's really no right or wrong when it comes to Injector timing...run whatever you believe works best. On my setup, I have a more gradual increase in Injector timing values as RPM and Load increase with a CAP of 540° at the very top. Stopping injection at 540° ensures that you get the injector to stop firing before the intake valve closes AND that there's still enough air flowing to get the fuel injected into the combustion chamber.

But what you do with injector timing at high RPM/Loads is all academic. I don't know that it really makes any difference. The real differences, if noticed, will be at the lower RPM/Loads like idle, off-idle, and cruising.

_________________
...Always Somethin'

89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA

Member V8-Ranger.com

Ok now all this talk is about a N/A motor.But what happens with a blown car?Do the same theories apply.Stan

I have no clue. I've never read any articles that discuss Injector timing as it relates to boosted applications. There are 2 arguments that I would expect people to have about early or late timing during boost.

An argument for early timing is that fuel doesn't evaporate as fast under higher pressures so you want earlier timing to give the fuel more time to absorb the heat and get atomized. This would also help reduce intake air temps.

The argument against early timing in favor of late timing is that because the fuel doesn't evaporate as well under boost that you should spray as much fuel while the cylinder is aspirating as possible to take advantage of the turbulent airflow which will hopefully pickup more of the droplets and get them atomized vs letting them pool in the port before the intake valve opens.

I don't know which of these arguments is valid or if one is valid only at certain times while the other is valid at other times. With poorly performing injectors that don't atomize fuel well, I would expect the 2nd argument is more accurate. However with a quality injector that does a good job of fuel atomization, I don't know if the 1st argument has merit or not.

If you find an article that spells this out, post it here. I'd be interested in reading real test-cases where this, specifically, was studied.

_________________
...Always Somethin'

89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA

Member V8-Ranger.com