Zdaddy

I'm working with a factory stock 305 HO and a Vortech V7Ysi through a Spearco 6-Core intercooler. Went to the dyno last year with 30lbs Accel injectors, Walbro intake fuel pump and holley adjustable fuel regulator was able to yeild a pull of 385hp and 430ft lbs of tq. @ 4500 rpm. Could make a full pass due to leaning out. Went back again couple months ago having install an external sump, Aeromotive A1001 fuel system and a Vortech Super FMU with 36lbs Accel injector and pretty much had the same results with a 410hp and 485ft lbs tq shuting down early at 4500 rpm again.

So here is the delima! The factory ECM will only recognize 16-14ohm saterated injectors, so 36lbs is close to the limit of availablity (I think anyway) so most folks like myself start looking at stand alone FMS. I was considering the Accel DFI Gen VII plus, but by the time I purchased that, another lap top, eight new injector, I would put out $2000.00 plus dollars.

After scratching my head a little, I remembered we purchase Turbonetics kits with a stand alone FIC that they package with the kits. These kits are produced by a company in the UK called Aquamist. It is a two or four injector driver that auto recognizes what ever injector type you chose and is fully programable (which Turbonetics doesn't want you to know) to 10,000 rpm via engine rpm and a 2 or 3 bar MAP sensor. The system is only $350 plus maybe $250 for the turndown, fuel bosses and line modifications.

I have chosen to run two 160lbs injectors (peak) which will still give me my factory driveability and tons of fuel on demand. Enought to max out at around 850hp according to my calculations.

I hope to go back to the dyno next week and tune my new little device. I promise it doesn't take a brain surgeon either. Nine interpolated screw pots and your done. MAPping and RPM do the rest.

Later

3.8TransAM

Have u been sleeping alot lately or just not looking real hard for injectors?

U can get all the way thru 90#'s for high impedance.

Up to the Motron 60/65#'s are economical however(very linear from low to high Pw's)

In addition stay away from any Bosch 42.5# injector due to their linearity.

Also dont trust any Accel injector, they have had issues for quite awhile, from bad windings to stuck pintles.

Ford/SVO are best bang for the buck type after the 36# u need to go elsewhere however.

After further reading, im thinking yoru problem isnt in your fuel system unless you have a real restriction somewhere.

Its more then likely your running a factory ecm and inadequate tuning.

After the MAF limit is reached the computer will only add in the commanded PE, it will not compensate for boost past that.

Look at using the 749 and %58or $60 code.

Your 20 yr old factory ecm is still more impressive than any aftermarket ecm, just takes a little more learning


later
Jeremy

D's89IROCZ

SO with the camanded PE ( MAF) ...can you still tune it ...whilst running a MAF then ? I am going crazy trying to find a good way to do it . But I am affraid to try and re wire my ECM to the 730 ( from 165) I am getting the Walbro 255 lph for forced induction setups with 50 lb injectors .... still not possible to run the MAF ?

Not to hyjack friend ...just relevant to MAF/ forced induction

Zdaddy

Shame you have to start your post with a little "ball busting" because you information seems helpful. I tried other injector combonations including the 55lbs 12ohm saterated injectors by MSD. They would run the motor fine at idle and cruise but at WOT would act like a rev limiter.... MSD said it was due to the difference in ohms from 14 to 12 that the OE ECM wouldn't recognize correctly. So is there an injector out there that WILL work with my OE ECM at 65-75 lbs???

So, more explanation of this please-

"Look at using the 749 and %58or $60 code. Your 20 yr old factory ecm is still more impressive than any aftermarket ecm, just takes a little more learning"

Thanks,

Brent
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NO, It's cool! I'm curious to read his reply as well!

junkcltr

iTrader: (1)

The $60 code is done. One person decided that it was not public anymore so now it is private.

The $58 code is a good starting point. The $59 would be the next step after that.

Some people just post what they have heard and have not actually tested or have seen test results. Ford green top 42#/hrs work fine with a 730 and SD ($8D) code. There are a lot of myths from the days of old about tuning them and non-linear pulsewidths. The ECM can correct for non-linear pulsewidths so it is a mute point. That is what the stock GM code does for all injectors.

The MAF ECM can be used for boost but is not optimal. You can set the PE MODE AFR richer and it will supply more fuel. The thing you can't do is supply more fuel vs. boost. It would have to be set to be rich enough at all boost levels and RPMs. That means it will be too rich at some points. It is not optimal, but will work if tuned with a WBO2 sensor.

On a very mild 355ci it would max the MAF around 4000 - 45000 RPM at 4PSI - 8PSI of boost. This is a rough estimate to show where the MAF will max out.

The problem of large injectors is more difficult with stock ECMs that do double fire batch mode. SEFI is easier because it does single fire so it allows the injectors to be open twice as long per engine revolution (2 crank revs).

Zdaddy

Well, I've read a lot a negative feedback on using the Aquamist FIC System. It was a little late to back out, had the system, already modified the intake and fuel system so I went forward with the project just a little worried.

Finished the installation today, did all the no start tests, pre-programed the unit and started the car.... After the car warmed up, gave it a few hard revs and the system came alive. Watched the l.e.d.s climb with the rpms correctly and the MAP sensor ligtht on at 10 psi. So all was well. Took the car out for a test drive and guess what????

THE FREAKIN THING WORKS GREAT!

What the hell is everybody talking about this system not working. I had great fuel enrichment all the way to 7000 rpm! And the car pulls it's *** off. No more leaning out at 4k. Can't wait to make it to the dyno to fine tune the car. And I did it all for $500 dollar!

junkcltr

iTrader: (1)

No one here said the sysem wouldn't work. People posted info about everything but the system. Of course it will work. You are spraying fuel that it needs and it also is pulling heat from the air (intercooler effect).

$500 isn't bad. You could have also sprayed water/alky at it for the same affect. Probably would have cost about $250.

83 Crossfire TA

iTrader: (2)

What high Z inejctors are there out there that are larger then the 65pph Motrons/delphi’s?


And

The MSD 50/55lb injectors have a reputation for being slow and hard to tune, and I’ve always felt that you start running into issues with single fire vs double fire with the GM ECM’s with injectors >36pph, but after experimenting with some MUCH larger high Z injectors in double fire, batch mode on my brother’s car running a haltech (the actual hardware driver is similar), I’m starting to suspect that it’s more of a code problem then a hardware problem, junckcltr or anyone with some experience here I’d really appreciate some input.

I know that I didn’t have any issues with making 36pph ford injectors idle with my ‘165, ‘730 or ‘749, where some people complain that it’s difficult/touchy, but I did have issues with a set of 30’s, so I consider it dumb luck…

How do you complensate for non liniar pulse widths (in my case I’m playing with a 749 now, so if it’s different then that’s probably where to direct the answer)

junkcltr

iTrader: (1)

The largest sat. injector I have used is the Ford green top 42#/hrs in the car right now. I hate the noise they make compared to GM 24#/hrs. I have never tried the MSD injectors. I spent some time playing with the $8D code a few weeks ago. I noted the following:
1) the ALDL BPW is not the actual BPW sent to the injector driver
2) my car spends a lot of time in $8D single fire mode when is decel mode (not DFCO).
3) The $58 code doesn't have the resolution that the $8D does and does not handle larger injectors as well.

Yes, I think it is more of a code problem for the GM ECMs. They have a decent injector driver ckt. In terms of the code, the $8D produces a great idle with a small amount of tuning compared to the $58 at idle WITH LOTS of tuning. BTW, the $8D reports my idle BPWs at around 1.2ms, but when I spit out the real BPW (with battery correct and low BPW correction) it is around 2.0ms. This is well within being a controllable idle / light throttle cruise BPW range.


165 and $6E, 730 and $8D have code that seems to deal with larger injectors OK. $58 doesn't do it as well but you had stockish sized injectors in it for $58. Both $6E and $8D can handle fuel transition modes well. $58 is a joke. GM dropped the ball on that one in terms of custom tunes. What do they care though. It was only intended for the Syclone/Typhoon so I guess they had it right.

It isn't about the ECM. It is about the code and injector. Look for a table that specifies injector offset (microseconds) vs. injector BPW. When the injectors get into low BPW you need to add ON time depending how non-linear they are. This table adds more on time to the injector vs. the desired injector ON time......kind of redundant. Both the 730 ECM and 749 ECM have the same injector driver ckt for saturated injectors. The 730 ECM only has one driver. The 749 ECM has two. Both can drive 8 sat. injectors. The 730 can drive 4 low-z injectors. The 749 can drive 8 low-z injectors. Resistors need to be changed. Yes, I verified all this myself......got some 55#/hr low-z's to install when the IC, water inj., and HX55 go on. Well, if I can ever get this plow truck ready for the snow and spend some time on the car.

D's89IROCZ

Hay guys great thread . Whats a FIC ? Just trying to learn more lingo for my searches on what I can use with my 165 set and $6E