comerz1

Ok guys, complete new tuner here. I have searched to the ends of the internet and have not found this information, only guys LOOKING for this information. So I hope this helps someone out there. I honestly am not even sure what the second table is for, maybe someone can clarify that for me. I was told these numbers are good for ALL accel injectors up to 75lb/hr.

Volts Dc uSec added
0.00 701.91
1.6 701.91
3.2 7782.09
4.8 7782.09
6.4 4455.63
8.0 2044.71
9.6 1464.86
11.2 1068.13
12.8 793.47
14.4 579.84
16.0 396.73
17.6 244.14
19.2 91.55
20.8 0.00
22.4 0.00
24.0 0.00
25.6 0.00

Also this information was sent to me

BPW mSec Usec Added
3.9 0.00
3.66 0.00
3.41 0.00
3.17 0.00
2.93 0.00
2.69 0.00
2.44 0.00
2.20 15.26
1.95 30.52
1.71 45.78
1.46 61.04
1.22 76.29
0.976 91.55
0.732 152.59
0.488 274.66

Hope this helps someone. I called Accel tech support and they directed me to a company that does their EFI tuning, or something of that nature and the guy there was nice enough to forward me this info.

comerz1

Well when I submitted it, it changed the format. If I knew how to insert a table I would do that, maybe someone else could be so kind??

Tuned Performance

iTrader: (92)

The fact they actually handed this out is amazing

same as the aujp with bosh type 2 Multi- Tech's.

comerz1

Well I posted these too quick I suppose, looks like the exact same values already in the AUJP bin. Oh well, at least I know for sure now!

RBob

iTrader: (1)

Use the {code} & {/code} modifiers. Be sure to change the braces, {}, to brackets, []

RBob.

Dominic Sorresso

So are you saying these offsets are not valid? Having 21# Accel injectors in my LT-5, I've been looking quite some time for these. I called Accel and was told they didn't know what I was talking about. I'll need to check the values in the stock bin to see if they are the same.

Tuned Performance

iTrader: (92)

Of course prestolite performance said they didn't know. I swear the guys on the other end of the line have no clue whats going on with there products. I compared the values to aujp and they are the same.

comerz1

Dominic,

To the best of my knowledge they are valid. I called Accel requesting this information, which in turn told me to call a Company that does all of their EFI tuning and calibration. I was just a little surprised to find the values matched the ones in the AUJP bin precisely. But, like you I have been searching for these for some time and now feel I have a definitive answer, so hopefully that will help others out. I really don't know why I was so surprised, I figured someone else made their injectors as I have seen discussed many times, so it only makes sense that it matches other data out there.

comerz1

And if anyone wants to know who provided me this information, it was a company called Hesco. I have personally never heard of them, but they look pretty legit looking at their website.

Dominic Sorresso

I went back and checked a stock cal for the LT-5. It used the Bosch Multec inj. and I have attached a screen shot of those values v the ones given you.
Overall, based on FP, the values are the same. Based on voltage variation, some values are nearly double what the stock settings are. It has been my understanding that the Accel injectors were actually manufactured by Lucas.
AES supposedly has a database of Injector Offsets for use with their gear. The 21# Accels are pretty popular and they have performed flawlessly in my motor for over 4 years now. I may give AES a call and see if they have the values for the Accels and would they share them. If you know of anyone using the AES gear, their software supposedly comes with that database for easy access.
I will say this. I recently bumped the stock values by 10% in the 12-16v range and have found the AFR readings from my WB to be more steady and have a tighter variance. So when comparing the values in the tables you provided, increasing the offset could be moving in the right direction. Right now the VEs climb pretty quickly off idle.

Tuned Performance

iTrader: (92)

I contacted south bay fuel injectors a while back and if you send in your injectors they will test them and provide the offsets. I'm not sure what the charge is. I was trying to help a member here with his D1810BA from petronix That he got with a engine he put into a hot rod. Petronix wouldn't give out any information they wanted me to prove I purchased them first. I'm really not sure why is this such a secret

Dominic Sorresso

I contacted Tech Support at AEM Power having read that they maintain a database of Inj. Offsets for the ECUs. Apparently, they test injectors themselves and maintain these values so users can access the correct offset.
They did not have values for the 21# Accel Injector however they do have them for the 55# and 83#. I have attached a brief chart for the Offset values AEM uses with Accel 55# injectors installed. The units are in milliseconds. Looks like its quite a bit longer than what is in the stock bin but that could explain why motor idles rougher after long hard drive and fans are on sitting at a light. Comerz was told the values are the same for Accel up thru 75#. Be worth trying these and see what happens once the weather gets a bit warmer.
Just to reiterate, these values are derived fro AEM testing the injectors themsleves, not from the manufacturer.


P.S. Just looking at the ones Comerz posted, they're close to the ones I have here so maybe some additional confirmation.

the blur

So your saying the accel's are a direct swap, without tuning ?

Tuned Performance

iTrader: (92)

according to the information comerz1 obtained from accel's out sourced supplier yes.

Dominic Sorresso

One caveat for this. The offsets I posted are for 55# injectors. According to comerz, Accel offsets are supposed to be the same for injectors of 19-75 psi.
We know that injector opening time is proportional to pressure so I would assume the offset is correct for the rated FPressure of the injector.

the blur

Are the Accel's rated at the same FP, as the OEM multieks ?

Dominic Sorresso

You'd need to look that up but in the case of the LT-5, the Bosch Inj. are rated 22.78# at 43psi rail FP. The Accel replacements are rated at 21#
w 39psi FP. So at 43# FP, they are very close to the Multecs used in the
LT-5. I make no change to the flow rating in the cal to accomodate these injectors.

Tuned Performance

iTrader: (92)

I have always thought it odd they list ford replacement and gm replacement as the same but that can't be because of fuel pressure changing the #hr rating.

Dominic Sorresso

Another FYI, if the offsets are at the rated FP, that must mean at higher FP, the offsets would increase due to higher pressures increasing injector opening times.

Tuned Performance

iTrader: (92)

they must all rated at 85% duty cycle

Dominic Sorresso

Does anyone know if there is even a standard for rating injector flow?
RBob?

comerz1

Sorry for the delay in getting back to this. You guys have proved one thing to me here, you have a better understanding of injector characteristics than I do. lol

I do know the accel injectors are rated at 39.2psi. At least we have something to talk about, and maybe with the supplied data, you more knowledgeable guys can prove/disprove the accuracy of it. If it weren't so darned expensive I would just have a set flow tested and it would be done. Anyone know of an injector, with known data, that is comparable in price to the accels? Anyone have any bad experiences with accel? As hard as they are to get to, I don't want to have to mess with them too often.

I might also add, I did have an issue with a couple of mine leaking at first. Had to change a couple of o-rings to get it to stop.

comerz1

While this is not an "answer" to your question, and complete speculation on my part, I would assume, accel being the performance conglomerate that it is, decides what "flow" they want to market their injectors at, then figure out what pressure it takes to make the injector flow at the "marketed" rate. Calling and asking what pressure they are rated at provided a quick answer of 39.2. I am new to all of this, but so far in all of my studies into tuning, I haven't ever seen anyone mention a factory set up having an operating FP of 39.2, so why would accel rate their injectors at this FP? Maybe because it allows them to market the injectors at a nice round even number. Just a thought.

Dominic Sorresso

Comerz,

The Accel 21# are used as the replacement injector for the Mustang. FP is 39psi.
Using them for other applications like the LT-5 requires recalc due to different(higher) FP.
So now I'll be incorporating this new data into my calibration and datalogging it.
Hopefully, it will lead to a smoother VE fuel map and my WOT VE won't be tapped out at 99.9%

comerz1

Man that's a super nice set up there! Report back on your datalog results. I am now working with the $0D bin, and haven't looked at the values yet, but betting they are different. So it would be nice to have an idea where to go with these values.

EagleMark

Accell has the correct information for these but you need to have/purchase CalMap Pro version.
I guess the point is DON'T BUY ACCELL injectors! Or anything for that matter...

comerz1

I typically try very hard to stay away from accel, I just haven't had good luck with many of their products. However, when searching for injectors for my project, cost was a factor, and the accel were simply more cost effective than other alternatives I could find at the time. I should have been doing all of this homework BEFORE I started this project. (That's a tip to any of the new guys out there, and yes I realize I am still very new too).

While I can't do it at the moment, I would be interested in 'upgrading' to a better injector in the near future, you guys have any input on it? Anyone replaced accel's with something else and found an improvement in performance?

Tuned Performance

iTrader: (92)

southbayfuelinjectors bosh3 have a great spray pattern a little noisy though.
http://www.southbayfuelinjectors.com...7&product=1503

Dominic Sorresso

The Accel 21# injectors are well suited for the LT-5 application and cost effective. Have been using them for nearly 4 years and they haven't missed a beat so I can't bitch.

Dominic Sorresso

Well I thought I would update all on this. Over the last few weeks I put together a bin that incorporated the Injector Offsets very similar to the ones listed in this thread for the Accel injectors. I also modified the MAT table to reflect the sensor being used an IAT. Weather is cloudy today expecting snow and temps around 31F. Downloaded the bin into the Ostrich and started the motor. With the increased time offsets, I expected the motor to be a bit richer and it was. However, what a difference in the idle! I have a single mass flywheel and in combination w a ZF-6 Black Tag 6speed, you can get a rattle coming from under the car at idle. The smoother the idle, the less the rattle. During warm up, I got little to no rattle. Motor idled down smoother than I recall before. Once it went C/L, WB was showing 14.7 with a tight variance. It was better than I had expected. Looks like I can lean out the O/L CTS table by about 8%. We're expecting 5-10" snow today and car is on jackstands for replacing brake fluids and rear lines. I won't get a chance to take her out for another week or to see what cruise is like, but I am pretty pleased w the result so far.

Dominic Sorresso

As update to this, I made the change to my Inj. Offset and finally had an opportunity to datalog this car this weekend. As expected, it was rich just about everywhere but I resisted the temptation to just make a global VE table change.
There were areas where the BLMs very close. Most of cruise and idle were rich.
I have a tool that a friend developed which takes the datalog from my scantool EASE and crunches the new VE table. I am curious to start refining the tune even tho the car ran pretty well as is.


RBob,

Here's a question on recalc of VE. Once the adjustment % is calc'd would you apply it to the value in the VE table only or to that value + the VE Offset total?
I would think it is the latter. I assume you eventually get there doing the former but it takes more iterations.

Dominic Sorresso

After several datalogging sessions, I decided to go back to my original offset + 10% on relevant BAT V from about 10-16v. Using the larger injector offsets just pegged my BLMs to the rich side w little improvement. In fact, the "split BLM" issue seems to have been magnified. I have a greater difference between left and right banks than before. Right bank running rich, left on the other side of 128. One other change I made was to the MAT Comp table to utilize the sensor as an IAT instead. Looking at the logs, the air temp really doesn't go above 25C, so I have lowered the factor or multiplier at those points.
Going back to the Split BLMs, I did see that my Left O2 was giving me quite a bit fewer cross counts than the right side. As an example, my idle settled in at about 133/115 L/R BLMs. The right bank is generally rich all the time. Made some mods to VE and will do another run today. Weather looks good. I won't spend a ton of time on this until after we do an exhaust cam swap later this week. Then time to re-do the tune, but I wanted to get current (base) tune closer first.
As part of the upgrade, I will replace the O2s as they have about 10K miles on them. Good time to replace them.

Dominic Sorresso

So here's a bit of a twist to my little adventure into Inj Offsetland. In the last week, the LT-5 is undergoing a bit of an upgrade. We're installing somewhat larger exhaust cams to go along w the larger intake cams installed previously.
LT-5 heads are pretty efficient when it comes to exhaust so even tho I have ported heads and intake, I thought I would try and see if more intake from the cams could be handled by the stock exhaust cams. Specs for the re ground cams are:

Regrind Intake Camshaft 236d .425"@.050
Regrind Exhaust Camshaft 220d .425"@.050

The stock LT-5 cams have a primary and secondary lobe. The re-grinds are single pattern. The stock exhaust is a 214 w less lift.

In the process of the cam install, which in an LT-5 requires pulling the motor for easy access, I found the likely culprit for the wide disparity in my L/R BLMs
Exhaust leak at the left side collector. Bolts came loose at the flange.
So once the motor is back up and running I may be trying this again.

EagleMark

Dominic, have you had any issues with these injectors in deceleration? In data logs PW or if you have WB going extremely lean like DFCO? Then they come back slow and spike on and off?

Dominic Sorresso

EM,

No so I have I noticed. Motor behaves pretty well on decel. I do have DFCO OFF.
The LT-5 is a motor that WANTS to stall, and when modded this tendency is increased. So avoiding big transitions is a key factor. Taming prop gains, DFCO,
and smoothing VE/SA all help with having a "calmer" motor.

EagleMark

Thanks!

I was wondering if these injectors had any bad habits. Got DFCO off, but these injectors act as though it's full DFCO?

Must be another issue...

Dominic Sorresso

I have 16 of them. Primary and Secondary. After 4 years, we checked to see if I had a leaky one.

NOPE!

drive it

iTrader: (1)

I've been going in circles like a lot of folk on tuning large injectors.

Accel's most recent injectors look to be reliable from researching them, and they now post injector offset tables for all of them!!!

About time, and all other manufacturers should take heed!

I know where I'm buying my injectors from now on.


http://www.accel-ignition.com/produc...injectors.html

Just click on the part number for specs-and they are rated at 43.5psi.

Dominic Sorresso

Holy crap! FINALLY! Now I want to see how close I got this. Damn it. It's winter and I'll need to wait till spring to try this out.

1tpi

Dominic Sorresso

They're a bit of aholes however. They post their injector offsets for everything except the ones I'm using which are the 150121. Now these were rated 21# but at 39psi, so maybe the 150124 , the 24# rated at 43.5 would be very close for the offsets.

drive it

iTrader: (1)

Making any progress?
Makes sense-looking at all the offsets between their injectors they look to be progressive/predictable offsets between the lb/hr ratings.
I've got a set of Accel 48lbers on the way. It'll be interesting to see the diff when I install them and plug in the volt offset. I still haven't found an actual pic of the spray pattern on them, but figure with their 3 hole nozzle they have to be way better than the lucas single hole that I'm running now.
Then for the bpw table I'll switch between sf and df mode to fine tune that one.

Dominic Sorresso

driveit,

I have compared the 24# injector offsets with the one I am using as of the last calibration. Overall, the differential is ~20% until you get to 14.4v. There it goes to ~40%. Looking at my logs it appears that the BATT voltage is consistently at 13.5v +/-.1. So the actual offset is midpoint between the 14.4 and 12.8v values of the table. Just curious but I would think that w more voltage available the offset differential would be smaller not larger. Maybe someone could explain that. Overall, these new values are a small increase compared to the previous I had been trying that bumped the IB over 100%.
Anyway, I have made the changes to the cal but right now I don't have an opportunity to drive the car given the weather and the fact that I have the interior torn out installing new carpet and trim. Going from black to a Cognac
interior which I think will look classic w the Black Rose paint. Hope to get a chance to try things out whenever nice weather allows.

Attached is the table w the changes I made and then the table I had.

Dominic Sorresso

Just went back to do another check. Link is now broken. Anybody grab a few screenshots of this?

drive it

iTrader: (1)

Yea what's with that!? I will bitch at them to put them back up! Here's what I saved.

Dominic Sorresso

Thanks drive it. Don't have access to my .xls but it looks like there's little diff in the opening times for these injectors at the more relevant voltages. Be cool to just have a spreadsheet for offsets w standardized voltages x injector capacity.

EagleMark

They have changed the website! Go to this page and click on injectors you have for seprerate injector data sheets.
http://www.accel-ignition.com/products/efi.html

Dominic Sorresso

Eagle,

You are a scholar and a gentleman. Thanks. BTW, re-read ur post re: the ACCEL injectors on decel. Thinking about it, I have noticed that at times of decel, my WB will go to 21:1 indicating shutdown even tho DFCO IS DISABLED IN THE BIN. Is that what you were referring to, and what are your thoughts on that.

EagleMark

I think I got most of that calmed down with Decel Enleanment adjustments.

But now that we have actual data for these injectors I'll be retuning this vehicle from scratch again...

Man it was a lot of work to make it run right all the time, cold start and hot start were a PIA! I've turned away every tune since that had injector change and no data/specs...

Dominic Sorresso

EM,

That's pretty much where I'm at. I was excited to see the results of the changes in IB even before seeing these tables. So I am really looking forward to using these values and what turns out for a tune. As I said previously, this last set of values was closer and the tune was getting close much quicker w fewer iterations. And of course, RBob has confirmed for us the importance of using correct offset values. In the meantime, looks like I'm shoveling quite a bit of snow.