fuel management after 8psi

[fred slawson]

Did a search and only found one posting on aftermarket electronic fuel management, the Apexi Super AFC. Can this be used on the 2000+ cars. Also what about other electronic systems out there?

[Tiago]

it might be able to be used, it just alters the MAF signal to trick the computer into richening or leaning out the mixture. It should work.

[fred slawson]

Guess I'll have to get off my lazy butt and get ahold of an apexi installer to see if it will work.Thanks Tiago.

[nocutt]

<blockquote>quote:</font><hr>Originally posted by Tiago:
it might be able to be used, it just alters the MAF signal to trick the computer into richening or leaning out the mixture. It should work.<hr></blockquote>

Having used most of the "blackboxes" available for fuel enrichment...I will say the best I have used is by a company called link electroysystems: turbolink. (well technically it isn't a black box for fueling but for ign retard it is)
Although I think after 8psi I will suggest a reprogram that way you can run 36lb or 42 lb squirters...but that is just me...because all this "blackboxes" have a cap. Remember the MAF signal only goes from 0-~5Volts nothing after that. That means even a 36 lb injector might be an issue at idle and cold start...I will go for a reprogram as my first choice, extra injectors as the second, black box third and perhap an FMU...and that is a big perhaps! :(

[Arctc Wolf]

Stand alone engine/fuel management system. it may not be smog legal, but it'll allow for precise tuning of all parameters. the only well-known box that I think would work on our cars is the AEM EMS. I would try to find out the stock PCM settings, and change the one's that require changing, like knock sensor sensitivity when a larger cam is put in, injector sizing when bigger injectors are used, ect.

What I'd like 2 do, is get the setting from our PCM put into the EMS and get it smogged. I'd like 2 see if it'll still pass smog, even tho I know it probly would. then, when parts were added like cam's, injectors, SC/Turbo, ect., you could re-tune the PCM to handle it and keep the engine running smoothly.

[fred slawson]

Nocutt where would I place the extra injectors? Are you referring to an AIC type unit?

[fred slawson]

Artic Wolf, stand alone would be nice but I just don't want to pay the price. Pure poetry huh.

[hawgs]

<blockquote>quote:</font><hr>Originally posted by fred slawson:
Artic Wolf, stand alone would be nice but I just don't want to pay the price. Pure poetry huh.<hr></blockquote>

stand alone fuel management system, not a bad way to waste 10 grand

[Arctc Wolf]

haha, F&F talk. he added 1 too many zero's on that one. I've seen the EMS go for $500-$1000, so basically a little mroe than the cost of custom programmed PCM.

[nocutt]

<blockquote>quote:</font><hr>Originally posted by fred slawson:
Nocutt where would I place the extra injectors? Are you referring to an AIC type unit?<hr></blockquote>

Ideal place is 6-8" away from the TB, on the intake piping...but there is also another issue...I run a LT1 MAF in front of the turbo...I don't know if you guys are going to be blowing thru or suckin :rolleyes: thru. Therefore spraying into the MAF wouldn't be good thing! Yes it is an AIC. It will work pretty well for you guys since the 3800S2 on the Fbody isn't a FWD plastic manifold POS. This system also helps cool the intake charge some and cool the valves that's even besides enrichment...not bad although I still think a reprogram is better. I don't know about the f-body trannies (I do know the A4 are electronically governed) I don't know about an Aftermerket PCM support for this option. In other words, those with A4's might not be able to use an aftermarket PCM.

[BrianC72mg]

There are a couple of ways to do this.

You could use a boost sensitive variable fuel pressure regulator, supplemental fuel pump, and MSD turbo ignition control for modest boost levels. The variable regulator senses boost and then increases the fuel pressure at the fuel rail allowing the injectors to squirt more fuel given the same opening duration. The MSD box will pull timing on boost to prevent detonation, and the additional pump allows the fuel pressure to reach the 100 psi mark at maximum boost.

However the "best" method is a standalone ECU. The Haltech E6K can be had for around the $1,000 mark and was designed to work with GM components. They are based out of Australia where GM (Holden Commodore for instance) rules the roost. Another system the TEC2 & now the TEC 3 would set you back for around 2,000. The nice thing about the standalone route is that you can increase the injector size (rather than monkey around with variable fuel pressure) and then shorten the amount of time it opens at idle but still have enough capacity at say 80-90% duty cycle to support fuelling at redline under full boost. A Haltek E6K with harness, second hand injectors and a 2 or 3 bar map sensor can be had for $1,300-$1,500.

Installation is not too hard - just requires time and patience. Tuning is another matter. You could do it yourself with a wideband 02 sensor, EGT guages and a bit of luck.

Regards,

Brian

[nocutt]

<blockquote>quote:</font><hr>
There are a couple of ways to do this.

You could use a boost sensitive variable fuel pressure regulator, supplemental fuel pump, and MSD turbo ignition control for modest boost levels. The variable regulator senses boost and then increases the fuel pressure at the fuel rail allowing the injectors to squirt more fuel given the same opening duration. The MSD box will pull timing on boost to prevent detonation, and the additional pump allows the fuel pressure to reach the 100 psi mark at maximum boost.<hr></blockquote>


100 psi fuel pressure!...yes but raising fuel pressure for fuel enrichment especially after 7 psi isn't reliable...and that is amongst other things!


<blockquote>quote:</font><hr>However the "best" method is a standalone ECU. The Haltech E6K can be had for around the $1,000 mark and was designed to work with GM components. They are based out of Australia where GM (Holden Commodore for instance) rules the roost. Another system the TEC2 & now the TEC 3 would set you back for around 2,000. The nice thing about the standalone route is that you can increase the injector size (rather than monkey around with variable fuel pressure) and then shorten the amount of time it opens at idle but still have enough capacity at say 80-90% duty cycle to support fuelling at redline under full boost. A Haltek E6K with harness, second hand injectors and a 2 or 3 bar map sensor can be had for $1,300-$1,500.

Installation is not too hard - just requires time and patience. Tuning is another matter. You could do it yourself with a wideband 02 sensor, EGT guages and a bit of luck.
<hr></blockquote>

This will work for the guys with a manual tranny however it will take more ingenuity to use this option for an A4...but then again...I do agree that this is a better option...however the pricing still puts it on a lesser priority IMO :(

[ June 27, 2003: Message edited by: nocutt ]</p>

[BrianC72mg]

Thinking some more about this...since the auto tranny is controlled by the PCM, you could use an aftermarket ECU in a piggyback configuration firing extra injector(s). I'm not too familiar with this setup and there may be some cheaper controllers short of a full blown ECU. But then you get into the "bunch of boxes" issue - one for extra fuelling, another for ignition retard, maybe a J&S knock sensor....messy messy messy.

The sweetest deal (and probably far less expensive) would be oversized injectors and a re-flashed PCM. Easy installation and "easy" to return to stock. For the 3.4 the pickings are slim. I think there is a guy in Australia that has software for the same year V8s, but I don't think the 60 degree 3.4 is supported.

Does anyone know otherwise??

[nocutt]

<blockquote>quote:</font><hr>Originally posted by BrianC72mg:
Thinking some more about this...since the auto tranny is controlled by the PCM, you could use an aftermarket ECU in a piggyback configuration firing extra injector(s). I'm not too familiar with this setup and there may be some cheaper controllers short of a full blown ECU. But then you get into the "bunch of boxes" issue - one for extra fuelling, another for ignition retard, maybe a J&S knock sensor....messy messy messy.

The sweetest deal (and probably far less expensive) would be oversized injectors and a re-flashed PCM. Easy installation and "easy" to return to stock. For the 3.4 the pickings are slim. I think there is a guy in Australia that has software for the same year V8s, but I don't think the 60 degree 3.4 is supported.

Does anyone know otherwise??<hr></blockquote>


I am very sure one can run an aftermarket PCM and use the stock PCM as a piggyback to run the tranny In theory it is possible, in the real world it might be more difficult?

Also the problem with getting a reprogrammed PCM, you have to get a dyno time and have it tunned properly...although each time you go ~3% +/- on boost you will skew the tune...now I think that also depends on the state of tune...but 300/500 bucks for a each tune quickly adds up?!?!