Fuel Injector & Pump Output

[bhonebrink]

Can anyone tell me what the rated output of the stock injectors is? I'm doing my calculations for adding a turbo and will need about 40gal/hr or 461cm3/min per injector. I'm assuming I will need to switch to higher output injectors but don't have a baseline. Also, how about the fuel pump output?

[RRoller123]

There was a chart here a long time ago, listing this exact data for various injectors, I will look for it, but I doubt I can locate it. Maybe someone here remembers? In the meantime, you may need to play around with the AFR, so here is an instruction on how to manipulate the AFM:


"Step 12 Advanced Air FLOW Meter adjustments for best emissions and power. (note: This procedure is for all L-Jetronic Alfa Romeos, Fiats and Lancias.)
Many of our friends in the Italian car community are buying and using Air Fuel Meters (don't confuse that with the Air FLOW Meter). These devices are worthwhile because they allow you to accurately monitor you fuel mixture. However it's important to understand these devices read out put information from the O2 sensor and are entirely dependent on a good O2 sensor for accurate data. That's one reason most come with a disclaimer saying they should only be used to monitor mixture and or note changes to the mixture after engine modifications. It's also the reason most only display a range of readings (i.e. lean, good, rich or something like that). They almost never have a line on them saying "best power here". I am not going to leave you wondering exactly where the best power setting is, but, like them I need to make a similar disclaimer. Unless your O2 sensor is really really good, as in like new condition it may give incorrect readings which could cause this whole procedure to be harmful to you engine's performance. The good news is that with an excellent O2 sensor and a high quality DIGITAL voltmeter you can set mixture very accurately. In fact, the only way to do it better would be with a chassis dyno with an exhaust gas analyzer.
Since we will be measuring mixture by reading the output voltage of the O2 sensor we will need two things. First a good DIGITAL voltmeter. A cheap one won't do it, we need a good one with a digital readout. Next we need to make sure our car has a good O2 sensor. If your O2 sensor is questionable there isn't much point in trying to set mixture using information it provides.
Before I go any further I need to discuss the O2 sensor. This device measures exhaust emissions and sends a signal to the ECU to lean or richen the mixture. It only has an effect at part throttle. At full throttle it's signal is locked out by the Throttle Position Switch, and at idle it can't generate a signal because it doesn't have enough heat. The problem is it's self powered, it makes its own electricity from the heat in the exhaust. If there is not enough heat in the exhaust because the car is at idle it can't quite generate a signal. It also has problems generating a signal during the car's warm up period. Later cars have a 3 wire O2 sensor that receives electricity from the car's electrical system to heat it up. Those later 3 wire O2 sensors work a little better, but not much. *O2 sensors last a long time but they can deteriorate and when they do it will have an adverse effect on part throttle emissions and fuel economy. If your car won't pass an emissions test at cruise RPM then it could be the O2 sensor. Bosch says to buy a new one every 50,000 miles. I don't think that's really necessary. I have had pretty good luck removing and cleaning O2 sensors. However they can be damaged by contamination in the exhaust and other things so if in doubt buy a new one.
Now that I have stated the need for a good voltmeter and O2 sensor I will explain how to set your mixture for max power. It's really simple. First warm up the car. Next Connect your voltmeter to the output wire from the O2 sensor (the connection is on the right side of the engine bay toward the back, it's the only wire coming up from the exhaust area.) To do this you may need to disconnect the sensor but that's OK for the short amount of driving we will do to make the adjustments. If you did disconnect the O2 sensor ground the other connector (the one going to the ECU). This isn't that critical and will be temporary so just use tape or whatever you can find. Put the voltmeter in the car by having it's wires pass through the window and have a friend hold it for you and take the readings. Now go drive you car around and make a few full throttle max RPM runs while your helper notes the voltage. You may notice the voltage fluctuates a lot at low RPM but at full throttle above 2500 it should be steady, if not check your voltmeter connection and if it's good get a new O2 sensor. The voltage should be .88-.92 Volts. If the voltage is less your mixture is a too lean for max power, if it's the voltage is too high your mixture is too rich. If your mixture is below .75 it's dangerously lean because of a problem with the injection system. Most likely it's an air leak, throttle position switch problem or bad fuel injector or injectors. It could be other things but those three are the most likely. To adjust the full throttle mixture we have to adjust the Air FLOW Meter's spring tension as described in step 8. It's pretty simple, loosen the spring to richen the mixture and tighten it to lean it. Test drive the car after each change until you get a voltage reading in the correct range. Then remove the voltmeter hook the O2 sensor back up and secure the AFM's cover.
Ok, it's time for the idle mixture adjustment. *If your car has strange idle problems including a change in idle speed when idling for a long time after some higher speed driving, or the inability to pass a smog check at idle they you probably need to adjust your idle mixture. To do this you will need to hook up a good quality DIGITAL voltmeter to the O2 meter's out put wire, just like when we adjusted mixture for max power. Now start the car up and let it fully warm up. Once it's fully warmed up we need to read the output voltage of the O2 sensor at idle. But Wait! At idle the O2 sensor doesn't have enough heat to generate a signal. No problem, just rev the motor up above 2500 rpm for about a minute and there will be enough heat at the O2 sensor for a reliable signal for 30-45 seconds. That means you need to take the reading quickly but not too quickly. The voltage reading we want is .45. Of course it's not quite that easy to read, the voltage will appear to be all over the place, perhaps it will be .65 one second and .25 the next. If it is, that's OK, as long as the variations average out to .45, idle mixture is set correctly. If not we need to adjust idle mixture. This is fairly simple. On top of the Air FLOW Meter, near the output section is a round plug. This plug can be removed giving us access to the Idle Bypass Screw. The screw is at the bottom of the hole which is accessible once you remove the plug. It's usually an Allen fitting. Turning this screw adjusts idle mixture and nothing else. Make an adjustment, and then take another voltage reading, don't forget the rev the car up again first. Keep repeating this until your voltage reading fluctuations average out to .45. Then put the plug back in the Idle Bypass Screws access hole, put everything back together and you are good to go."

[RRoller123]

Here it is: (Injector Flow)

http://users.erols.com/srweiss/tableifc.htm

[rridge]

Bosch pumps were used across many applications including Jaguar V12s. The biggest difference among most is terminal configuration. Output is not the problem. Not true of off-brand pumps.

Fiat pressure regulators were not common. Fiat used a 2.5 bar fuel rail. Most Bosch Ljet systems used 3.0. Quoted injector flow rates assume a certain fuel rail pressure. Be sure you know what that is. Otherwise apples and oranges.

[SteinOnkel]

There was a chart here a long time ago, listing this exact data for various injectors, I will look for it, but I doubt I can locate it. Maybe someone here remembers? In the meantime, you may need to play around with the AFR, so here is an instruction on how to manipulate the AFM:


"Step 12 Advanced Air FLOW Meter adjustments for best emissions and power. (note: This procedure is for all L-Jetronic Alfa Romeos, Fiats and Lancias.)
Many of our friends in the Italian car community are buying and using Air Fuel Meters (don't confuse that with the Air FLOW Meter). These devices are worthwhile because they allow you to accurately monitor you fuel mixture. However it's important to understand these devices read out put information from the O2 sensor and are entirely dependent on a good O2 sensor for accurate data. That's one reason most come with a disclaimer saying they should only be used to monitor mixture and or note changes to the mixture after engine modifications. It's also the reason most only display a range of readings (i.e. lean, good, rich or something like that). They almost never have a line on them saying "best power here". I am not going to leave you wondering exactly where the best power setting is, but, like them I need to make a similar disclaimer. Unless your O2 sensor is really really good, as in like new condition it may give incorrect readings which could cause this whole procedure to be harmful to you engine's performance. The good news is that with an excellent O2 sensor and a high quality DIGITAL voltmeter you can set mixture very accurately. In fact, the only way to do it better would be with a chassis dyno with an exhaust gas analyzer.
Since we will be measuring mixture by reading the output voltage of the O2 sensor we will need two things. First a good DIGITAL voltmeter. A cheap one won't do it, we need a good one with a digital readout. Next we need to make sure our car has a good O2 sensor. If your O2 sensor is questionable there isn't much point in trying to set mixture using information it provides.
Before I go any further I need to discuss the O2 sensor. This device measures exhaust emissions and sends a signal to the ECU to lean or richen the mixture. It only has an effect at part throttle. At full throttle it's signal is locked out by the Throttle Position Switch, and at idle it can't generate a signal because it doesn't have enough heat. The problem is it's self powered, it makes its own electricity from the heat in the exhaust. If there is not enough heat in the exhaust because the car is at idle it can't quite generate a signal. It also has problems generating a signal during the car's warm up period. Later cars have a 3 wire O2 sensor that receives electricity from the car's electrical system to heat it up. Those later 3 wire O2 sensors work a little better, but not much. *O2 sensors last a long time but they can deteriorate and when they do it will have an adverse effect on part throttle emissions and fuel economy. If your car won't pass an emissions test at cruise RPM then it could be the O2 sensor. Bosch says to buy a new one every 50,000 miles. I don't think that's really necessary. I have had pretty good luck removing and cleaning O2 sensors. However they can be damaged by contamination in the exhaust and other things so if in doubt buy a new one.
Now that I have stated the need for a good voltmeter and O2 sensor I will explain how to set your mixture for max power. It's really simple. First warm up the car. Next Connect your voltmeter to the output wire from the O2 sensor (the connection is on the right side of the engine bay toward the back, it's the only wire coming up from the exhaust area.) To do this you may need to disconnect the sensor but that's OK for the short amount of driving we will do to make the adjustments. If you did disconnect the O2 sensor ground the other connector (the one going to the ECU). This isn't that critical and will be temporary so just use tape or whatever you can find. Put the voltmeter in the car by having it's wires pass through the window and have a friend hold it for you and take the readings. Now go drive you car around and make a few full throttle max RPM runs while your helper notes the voltage. You may notice the voltage fluctuates a lot at low RPM but at full throttle above 2500 it should be steady, if not check your voltmeter connection and if it's good get a new O2 sensor. The voltage should be .88-.92 Volts. If the voltage is less your mixture is a too lean for max power, if it's the voltage is too high your mixture is too rich. If your mixture is below .75 it's dangerously lean because of a problem with the injection system. Most likely it's an air leak, throttle position switch problem or bad fuel injector or injectors. It could be other things but those three are the most likely. To adjust the full throttle mixture we have to adjust the Air FLOW Meter's spring tension as described in step 8. It's pretty simple, loosen the spring to richen the mixture and tighten it to lean it. Test drive the car after each change until you get a voltage reading in the correct range. Then remove the voltmeter hook the O2 sensor back up and secure the AFM's cover.
Ok, it's time for the idle mixture adjustment. *If your car has strange idle problems including a change in idle speed when idling for a long time after some higher speed driving, or the inability to pass a smog check at idle they you probably need to adjust your idle mixture. To do this you will need to hook up a good quality DIGITAL voltmeter to the O2 meter's out put wire, just like when we adjusted mixture for max power. Now start the car up and let it fully warm up. Once it's fully warmed up we need to read the output voltage of the O2 sensor at idle. But Wait! At idle the O2 sensor doesn't have enough heat to generate a signal. No problem, just rev the motor up above 2500 rpm for about a minute and there will be enough heat at the O2 sensor for a reliable signal for 30-45 seconds. That means you need to take the reading quickly but not too quickly. The voltage reading we want is .45. Of course it's not quite that easy to read, the voltage will appear to be all over the place, perhaps it will be .65 one second and .25 the next. If it is, that's OK, as long as the variations average out to .45, idle mixture is set correctly. If not we need to adjust idle mixture. This is fairly simple. On top of the Air FLOW Meter, near the output section is a round plug. This plug can be removed giving us access to the Idle Bypass Screw. The screw is at the bottom of the hole which is accessible once you remove the plug. It's usually an Allen fitting. Turning this screw adjusts idle mixture and nothing else. Make an adjustment, and then take another voltage reading, don't forget the rev the car up again first. Keep repeating this until your voltage reading fluctuations average out to .45. Then put the plug back in the Idle Bypass Screws access hole, put everything back together and you are good to go."

There are glaring issues in this how to.

First and foremost, the stock 02 sensors on these cars are narrowband. That is ancient history. Hooking up a multimeter to the output wire is next to useless, as these sensors only report three settings "too lean" "Okay" "Too rich" and more importantly they are only remotely accurate around stochiometric. That's far too inaccurate for any meaningful tuning, especially on a boosted application.

Second, tricking the stock ecu into running rich by manipulating sensor values might result in more power in an N/A configuration, but suggesting that you can enrich it enough and accurately enough to run boost is a recipe for holes in pistons.

What OP needs is a new fuel delivery system. You can keep the lift pump, then you get rid of the stock high pressure pump. You can run Delco EP286. At 12 volts, the operating pressure is 70-95 PSI with 36-40 gals per hour.

Next up is Injectors. Go here:

https://www.witchhunter.com/injectorcalc1.php

For a boosted application you need to run a fuel pressure regulator that can sense manifold vacuum and boost. It needs a load reference. I run an aeromotive unit.

Lastly, and this is going to be the most involved part. You need a new fuel injection system that can accurately and quickly adjust your air/fuel ratios to suit your needs. I'm going to tentatively suggest a megasquirt 2. Better yet megasquirt 3 (knock monitoring would be nice) or ECUMaster Black. If you're going on the cheap side, build a Speeduino.

I would not start slapping on a turbo to the existing L-jet and then calling it good. One trackday or spirited drive through the canyon and your engine is done for. Unless you can source the original volumex car's components, but this is far more expensive than going standalone. Pluswhich, those components are 35 years old at best.

[RRoller123]

Don't shoot me, I am only the piano player. But the bottom line is that you can fool it by the position/tension on that door spring, making it think there is more or less air coming in than actually might be. Whether one wants to or not... well that's another story, and probably partially explains why we haven't seen a single turbo conversion discussed here in the 9 years that I have been on the page. I have not done this AFM fiddling myself, and it is obviously not for the faint of heart. Certainly would want an AFR gauge hooked up to monitor the whole thing. Sounds like Stein has experience with this, I would listen to him.

[SteinOnkel]

Don't shoot me, I am only the piano player. But the bottom line is that you can fool it by the position/tension on that door spring, making it think there is more or less air coming in than actually might be. Whether one wants to or not... well that's another story, and probably partially explains why we haven't seen a single turbo conversion discussed here in the 9 years that I have been on the page. I have not done this AFM fiddling myself, and it is obviously not for the faint of heart. Certainly would want an AFR gauge hooked up to monitor the whole thing. Sounds like Stein has experience with this, I would listen to him.

No worries, Roller. I know you didn't initially write that

There's usually a trick or two on any old fuel injection system to fool it. Some "chiptuning" companies will sell you a resistor that fools the ECU into thinking the engine is colder than it actually is, thereby forcing it to be stuck in Warmup Enrichment all the time. The more modern the car, the more you can fool the ECU, generally speaking. Nowadays with drive by wire and so on, you can dupe a consumer pretty easily into thinking his $500 tuner actually makes more horsepower. It usually doesn't.

It's also important to note that OEM juggle three things: Emissions, Performance and Reliability. Surely you can switch these priorities around and get better results in a single category. My VW puts another 25bhp over stock, but it's at the cost of reliability (the fuel injection is more complex than the stock unit) and of course emissions, which for my application the engine is exempt from.

My favorite hodgepodge method is on an old single point injection Opel I used to own back in Germany. It ran...Bosch Mono-Motronic I think. Anyway, by putting an m12 standard size washer underneath the injector nozzle, the car would inject exactly 25% more fuel across the board. Nonsensical, except for one use case: running e85 fuel. I ran it like that for years and if I was ever stuck without e85, simply pop the cover off and remove the washer. Fill up with regular fuel and off you go.

All of these scenarios I just described are naturally aspirated. With boost, there are no shortcuts. One look at a boosted fuel table versus an n/a one of the same engine will tell you that, you can't bs the ecu into dumping 30-40% more fuel into the engine (and only some of the time). You need the bigger cooler, nicer pump, injectors and lastly an ECU that can actually keep up. An L-Jet is far too slow to react and inaccurate. Let's not kid ourselves here, if the Volumex cars were any good, we would all be driving those instead of our carburettors.

[RRoller123]

Good point about the Volumex. I was always a little surprised at how little more they put out over the std Euro spec.

But hey, it's all good, the point is to have fun. If we wanted collector cars, we wouldn't have bought these fun little buggies.

[bhonebrink]

Thanks gentlemen for the replies. I have been planning on using a Megasquirt product for injection and ignition but was also wondering about the possibility of using a modified 'stock' set-up. Now I know better. I am currently working with DIYAutoTune to determine the best product for my application. I'm curious to hear about recommendations for higher output injectors and COP coils. I am currently looking at DSM 500cc injectors and DSM coils but has anyone successfully used a different product with MS?

[SteinOnkel]

I have done three MS installs to date. Two MS2, one MS3X.

They all have major shortcomings which is why they are so cheap.

The older the engine, the more you can get away with an MS2. As soon as you add knock sensing into the mix, go ms3 at a minimum. That's just one example. The amount of time I've run into a feature that can only be run with 3 and up is ridiculous. MS2 is more of a homebrew toy, MS3 is a serious engine management.

That being said, neither of them (except maybe the ms3pro) can compete with the other open source efis out there. Better support (this is a big one), better housings, more engineering all around etc. MS's support team is basically a forum full of people running this stuff on their mopar v8. If you have one of those, great, you're all set. But you don't. Also, none of the default anything will work on your car. The developers decided to focus their attention on engines such as a Rover instead of...oh I dunno...how about any 4-banger built in the last twenty years?

Would I put another MS3X onto my Derby? Nope. I would dish out the extra $500 and get a halteck, maxxecu, ecumaster etc etc.

Cheers
Steiny

[ORFORD2004]

My turbo setup run with megasquirt 2 and you can add knock sensor from a guy in Ontario that control your timing in megasquirt.

[SteinOnkel]

My turbo setup run with megasquirt 2 and you can add knock sensor from a guy in Ontario that control your timing in megasquirt.

You can also add it yourself, which is the whole point of megasquirt....

I think a turbo engine w/o knock sensing is only for those with deep pockets and lots of free time. OP would be much better off with any other of the aftermarket ecus.