USRT Fueling Solutions

[manchvegasmk11]

scott need help with my fueling issues- i have a low compression vrtwith a to4e tottally rebuilt bottom end and top end, running eip stage 2 chip and rising rate fmu, any way need to know about how many psi fuel i should be running i ask for psi because i dont have the gauge to test it in bar, and i want to be running 15lbs of boost. thanks mike

[Scott@USRT]

Okay, let's first put this reply in context. I do not believe that an FMU-based fueling scheme is optimal, necessary, or even wise. Modern electronic fuel injection permits the fuel curve to be dialed in with computer precision. A rising rate pressure regulator, on the other hand, creates the fuel curve mechanically. At best, it is a compromise. This method can certainly work, but never as precisely as an OEM-"proper" set up with bigger injectors, appropriate pressure, and software that is carefully tuned for the engine and its operating parameters.

I'd look to EIP for particular guidance about working with this FMU. They're clearly the masters of this technique whether I agree with their methods or not.

With that said, let's directly address your question. Your max fuel requirement is tied directly to the power that you intend to support. So, how much output are we talking about here? (Please clarify whether you're talking about whp or bhp/chp.) What compression ratio do you have? What octane level do you intend to tune with? Do you have a wideband to tune with?

Or... are you simply asking what fuel pressure in psi corresponds to a given pressure expressed in bar? Remember that 1bar = 14.5psi. And... considering that a fuel pressure gauge will cost you $25 or less, there's absolutely no reason not to have one (assuming you don't already).

[nypassat16v]

im sent

[CorradoCody]

Scott,

I tried emailing you, no reply. Can you please contact me in regards to an order I placed?

corradocody@comcast.net

CC

[foffa2002]

2 sets of VRT 24v 630cc injectors arrived today!
Thanks for fast shipping

[Residentevol]

Hi scott Im trying to figure out what I need to purchase as far as injectors/FPR and Fuel pump. I dont have the car yet Im moving to Germany but I have a lot of parts piling up to build one when I move there in march (air force is sending me to germany for 4 years!) so ive got a ABA16V that will be going into a Mk1 Golf or Polo. I have a BBM 16v fuel rail and I will be running Megasquirt v2.2 squirt and spark. I will have stock obd1 internals and a basically stock 16v head I know it does not take an amazing amount of boost to make this motor rock but Im shooting for a min of 300hp once its tuned and running. Plan on using a t3/t4 to get there.anyways what size injectors/FPR and Fuel pump would you suggest to fuel this project? I will be buying from you

I also sent this VIA IM sorry for the length

Just read another post so here are some added things you asked for to him.

Im looking for atleast 300 with as much as 350WHP
I am planning on running pump gas highest octane available in germany. I have an LM2 wideband to monitor my a/f and I will be using patatrons megasquirt setup.


Modified by Residentevol at 6:15 PM 10-18-2006

[Scott@USRT]

This is an easy question to answer. If the car you throw this engine in has/had CIS injection, then keep the stock pump set up. It will be more than sufficient for your needs. If the pump is dead or is a later model, then go for a Walbro inline or Bosch Motorsports "044". Either one can work great. The Bosch has a clear flow advantage at high fuel pressures, runs quieter, and is probably longer-lived. As for the injectors, go for some 630cc and run them at 3.5bar fuel pressure.

We can supply all of these bits. My only question regards which type of 3.5bar fuel pressure you can use. There are two versions. One fits the Corrado G60 rail (pictured below) and the other is the type that you see in the VR6 and 1.8T engines (seen above). Did you purchase an fpr adaptor with your rail?

[Residentevol]

yes and I bought it with an FPR that fits onto the rail itself I think it is either a 3 or 3.5 bar so I believe I am good to go in that compartment...my other question is I have a megasquirt setup and I read on your site that low impedance injectors may be used on some standalone...do you know if I will be able to use those with megasquirt? They sound like the better choice but I dont want to buy the wrong ones!

Thank you very much for the informative response I really appreciate the work and effort you guys do for us Vortexers!

Im not to sure of the fuel system that will be on the car but I will remember your suggestion if its CIS to keep it. the cars in germany that are all pre 1980 (the ones I am looking for) all seem to be carb'd engines what kind of pump did those use?

The FPR I have looks like the bottom picture. But I also have a 3 bar which looks like the top pic...


Modified by Residentevol at 7:13 PM 10-19-2006

[Scott@USRT]

Quote, originally posted by Residentevol »

yes and I bought it with an FPR that fits onto the rail itself I think it is either a 3 or 3.5 bar so I believe I am good to go in that compartment

Well, you're surely good to go if you've got a 3.5bar. If you have a 3bar, then you'll simply have to lower your output expectations a bit.

Quote »

do you know if I will be able to use those with megasquirt? They sound like the better choice but I dont want to buy the wrong ones!

Ask Pat if he set your box up to accept the low-impedance injectors. In this case, though, it really doesn't matter. My recommendation is to go with the Siemens 630cc injectors which are available in high-impedance only. These will idle just fine with careful tuning.

Quote »

Thank you very much for the informative response I really appreciate the work and effort you guys do for us Vortexers!

Thanks for voicing your appreciation. It keeps us motivated over here!

Quote »

Im not to sure of the fuel system that will be on the car but I will remember your suggestion if its CIS to keep it. the cars in germany that are all pre 1980 (the ones I am looking for) all seem to be carb'd engines what kind of pump did those use?

If the car was originally carbed, it'll be set up with a low-pressure pump. This will need to be replaced. If you get a CIS car, then you have the option to retain that pump (assuming that it is still functional, of course). These are all ancient parts, though, and since the pump is so important, it may behoove you to invest in a new one anyway.

Quote »

The FPR I have looks like the bottom picture. But I also have a 3 bar which looks like the top pic...

They all work the same. My advice is to use a 3.5bar of either variety. Go with what ever fits the adaptor that you purchased.

[nypassat16v]

IMs and email sent

[Residentevol]

Scott per my post above what if I wanted to lower my aspirations a tiny bit. perhaps to 250-300 hp would thos 630's be overkill?

[Scott@USRT]

Yes, the 630cc will be overkill, but there's nothing wrong with running a very low duty cycle. For 300whp -the upper end of your revised output goal -the Genesis 550cc would be perfect. They've definitely got the optimal spray pattern. However, they're the same length as the non-AEB 1.8T injectors (and are thusely about 8mm too short for the BBM rail). The Siemens 630cc at 3bar have a decent spray pattern and will fit your BBM rail directly. With the standalone management, tuning for idle with the 550cc or 630cc will not be a problem at all.

In short, the Genesis 550cc are the best-performing option *if* you extend the fuel rail extension tubes. The Siemens 630cc will work just fine in your 16v, however, and will drop right in.

[nypassat16v]

hey scott i want to start buying some of the stuff we discussed

[ForsFedRado]

Scott,
I am in the process of returboing my rwd 2.9 vr6 corrado, she's getting a pt67. I run Dta pro 8, aeromotive 1000 pump lines and filters/reg, -10 feed to pump,-8 feed to rail and -6 return. I need a set of injectors for my setup, fuel rail is 5/8 id and now te short runner is holding ford green tops. I need injector that will fit in there place and support 500whp.

thanks

[Scott@USRT]

Okay, this is an easy one. Run some Siemens 630cc injectors at 3.5bar and you should be perfect. This assumes that you're doing what you're doing on pump gas. With race fuel or water/alcohol injection you can make do with 580cc at 3bar. The 630cc are still advantageous, though, because they have a superior spray pattern with significantly better fuel atomization, too. Your DTA will be able to control larger injectors just fine, so you might as well go with the big guns.

Kudos to you, btw. You've taken no shortcuts with your fuel system so far. Do it once. Do it right!

[rado_speed]

Scott-
Ive installed your 42lb injectors in my obd1 vr6, along with c2's software and spacer. I ran into a problem with my intercooler and am now considering a water/meth set up spraying into a kinetic stage 1 turbo to TB hose. My question is whether or not it would be acceptable to be running the car at a low boost setting(9 psi unintercooled) with that much fuel until I get the meth kti since this set up is pretty much what c2 calls thier 17psi fueling kit.
Thanks


Modified by rado_speed at 5:54 PM 11-14-2006

[Scott@USRT]

Remember that even the biggest/baddest turbo engine is normally aspirated until the boost hits. So, although your C2 software is set up to supply fuel at engine loads that you'll never see right now, it is also just as dialed in for the lighter loads (from idle to 9psi) that you *will* see. Your air/fuel curve will not be any richer than normal even with the big injectors. You'll simply run a very low injector duty cycle which "wastes" the big injector's fuel flow potential. It's kind of like using a 911 Turbo only for getting groceries, dropping the kids off at the soccer game, etc.

Without an IC, however, your intake temperatures will be significantly higher than it was before. Again, you're not going to run any richer with this set up. So, you won't have the cooling effect of a very rich mixture. The water/alcohol injection (WAI) will serve as your primary defense against heat-related detonation.

With that said, you should be able to get along fairly well without either the IC or the WAI so long as you drive lightly. If you get a little bit too happy with the throttle, your knock sensor will pick up any noise and will prompt the ECU to retard the timing. That's no big deal. However, if you really get silly, you'll unleash the wrath of the hotrod gods.

[VW_NUTTER_ECOSSE]

PM sent re Spacer kit...

[Jeebus]

I've asked this a few times in different threads but I'd like to hear from you Scott.

With the Walbro pump....is that pump fine on it's own? Meaning if I ditch my factory pump and accumulator should this pump hold up fine? Running SDS EFI... with you 580cc injectors.

Oh and one other question... it may be a stupid one but there are two small plastic things on the + and - terminals on the pump... are they supposed to stay on there?

[shortshiften]

do you guys offer any options for vr6 fuel rails?

somthing where there is not fpr hole ??

[Scott@USRT]

Quote, originally posted by Jeebus »

With the Walbro pump....is that pump fine on it's own? Meaning if I ditch my factory pump and accumulator should this pump hold up fine? Running SDS EFI... with you 580cc injectors.

You should keep your stock transfer pump with accumulator and add the Walbro inline. Ditching the stock bits will gain you nothing, but will cause fuel starvation problems. As for the Siemens 580cc injectors, they will not fit your 24v cylinder head. The way to go is with the Siemens 630cc. Change the electrical connectors on them and you'll be good to go.

Quote »

there are two small plastic things on the + and - terminals on the pump... are they supposed to stay on there?

I'm looking at a Walbro inline pump right now and don't see what you're referring to.

[Scott@USRT]

I've got a VR6 rail in stock as we speak. Screw in a plug and be done with it. Why don't you need a return hole, though?

[Jeebus]

Quote, originally posted by Scott@USRT »

You should keep your stock transfer pump with accumulator and add the Walbro inline. Ditching the stock bits will gain you nothing, but will cause fuel starvation problems. As for the Siemens 580cc injectors, they will not fit your 24v cylinder head. The way to go is with the Siemens 630cc. Change the electrical connectors on them and you'll be good to go. I'm looking at a Walbro inline pump right now and don't see what you're referring to.

Thanks but I'm refering to my 16VT Rabbit project. What other options do I have since all the stock stuff has been ditched... meaning tank, fuel pump, lines all of it has been replaced.

[shortshiften]

Quote, originally posted by Scott@USRT »

I've got a VR6 rail in stock as we speak. Screw in a plug and be done with it. Why don't you need a return hole, though?

i have an aftermarket inline FPR
Billet fuel pressure regulator designed for 1000 hp series pump and fuel filter.
Features:
2 inlets / 1 return.
-10 AN inlet and -6 AN return (O-ring).
1/8" npt gauge port.
http://www.eiptuning.com/eip/f....html

i was under the impression that by using this i wouldnt need the one in the fuel rail. i could be wrong

[Scott@USRT]

You need a return port in the fuel. That's how the fuel gets out of the rail and into the fpr. Send me an email if you'd like to discuss what I've got further.

[Scott@USRT]

Quote, originally posted by Jeebus »

Thanks but I'm refering to my 16VT Rabbit project. What other options do I have since all the stock stuff has been ditched... meaning tank, fuel pump, lines all of it has been replaced.

You should set up your fuel system as your fuel cell(?) provider intended. The Walbro inline pump can operate by gravity feed. So long as it gets a steady supply of fuel, all will be well.

[Jeebus]

Quote, originally posted by Scott@USRT »

You should set up your fuel system as your fuel cell(?) provider intended. The Walbro inline pump can operate by gravity feed. So long as it gets a steady supply of fuel, all will be well.

Thanks again.

[VW_NUTTER_ECOSSE]

I have a built 1.8T, currently running Sard 700cc injectors - one of the injectors is 'suspect' so looking to change - also the idle is awfull... cold starts etc..

Looking for a good compromise to support my 400-450whp goals but still have some better idle characterisitcs.

Tell me the Sards are not the best option I assume - can you elaborate on the whys and sugest other options for me.

In tank walbro, Stock 3 Bar FPR & Standalone.

Thanks


Modified by VW_NUTTER_ECOSSE at 12:33 PM 12-16-2006

[Scott@USRT]

Okay, for starters what standalone management system do you have? Can it control low-impedance injectors? Secondly, are your SARD injectors lows or highs? Third, are you tuning with pump fuel or very high-octane race juice (or pump + water/alcohol injection)? Fourth, what is your compression ratio and what turbo is under the hood?

[VW_NUTTER_ECOSSE]

Quote, originally posted by Scott@USRT »

Okay, for starters what standalone management system do you have? Can it control low-impedance injectors? Secondly, are your SARD injectors lows or highs? Third, are you tuning with pump fuel or very high-octane race juice (or pump + water/alcohol injection)? Fourth, what is your compression ratio and what turbo is under the hood?

Dicktator - little known South African setup - http://www.dicktator.co.za/SOFTWARE.htm, Low impedance, Pump 99Ron, 9-1. Garret T3/T40E.
Might ditch the standalone in favour of another system with more 'local' support in the next few months.

[VW_NUTTER_ECOSSE]

Ok, couple more q's

The Genesis 550cc injectors - you state "The most advanced injector we offer, Genesis 550cc fire factory-correct dual spray cones with super-fast response and best atomizaton on the market today. Combine with 3.5bar fuel pressure regulator for compatibility with any 580cc software. Safe for up to 8bar rail pressure! Fuel rail spacers not required."

These are advanced - how? - so I run with a 4 bar FPR and we're talking around 600cc with as close to stock spray as possible..

Ideal if they give me nice cold starts and idle...

These drop into stock rail?

Why the..

Is this needed for 1.8T too? Confused

Thanks

[Scott@USRT]

Alrighty, so you're looking for 450whp and are currently using pump fuel. You'll need something like 750cc at 4bar to achieve this. A better idea, though, is to increase the octane with race fuel or water/alcohol injection and use a smaller injector that's easier to control. WAI costs more up front and but race fuel will rob you blind after a few tanks. (If you'd like to discuss WAI's merits, btw, I'll be happy to hash it out separately.)

Anyway, increasing your octane will also allow you to run an injector that's better matched to your engine. On that note, your SARD-brand injectors are ideal for an engine with a single intake valve because they spray a very narrow stream much like the now unloved Bosch "greentop" 440cc. Since they're low-impedance, they can open/shut faster than the greens which is great. However -as you've experienced -their wicked speed is still not enough to allow you to tune a clean and steady idle. Spray pattern is *that* important.

Quote, originally posted by VW_NUTTER_ECOSSE »

The Genesis 550cc injectors... (snip) These are advanced - how? - so I run with a 4 bar FPR and we're talking around 600cc with as close to stock spray as possible..

The Genesis 550cc (click above) are slightly modded Bosch EV-14 (which are Bosch's latest technology). Run them at 4bar and they'll flow 635cc. They have the exact same spray pattern as stock 1.8T injectors, have faster response times, take high fuel pressures in stride, and produce more finely atomized fuel than any previous generation. All that translates to more power, sharper throttle response, lower emissions, cleaner idle, easier tuning, etc.

The old-tech parts that we see in stock VR6, 2.0l 8v, AEB 1.8T, and all Digifant-injected cars are designated by Bosch as "EV-1".

Then, there are the EV-6 and EV-12 (e.g. TT225) generations in between.

Quote »

These drop into stock rail?

Yes, the Genesis 550cc fit directly in all 1.8T engines that originally came with EV-12 injectors. The AEB is the one 1.8T that we got here in the States that takes the EV-1, so these 550s won't fit AEB's without running new seats/bungs.

Quote »

Why the.. Is this needed for 1.8T too? Confused

The adaptors are required because the Genesis 550cc use a different type of electrical connector than is in our cars. Those adaptors make it a plug n' play conversion. Alternately, you cut off your stock connectors and swap'm over. Most prefer not to hack stuff up.

Anyway, though... the 550cc are not going to flow enough fuel at any pressure to help you do 450whp. It's the 630cc at least or (more reasonably) the 750cc that you need.

[VW_NUTTER_ECOSSE]

Thanks, realisitically I'll have to do the head before I'm 400whp+ so the 550's look ideal.

So... 4 Bar FPR, Set of 550's & the adaptors.... cut me a deal..

[bw_01jetta]

Hi Scott, I have a stock AZG MK4 2.0L and would like to replace the stock injectors/fuel rail with one of your aftermarket setups. I need to get a set of injectors that will work with the stock setup until I can get the new cam and lifters.

After looking at the USRT websites injector page (and the associated descriptions) it looks like the Siemens 380cc would be the best option. Is that correct? I have already installed a highflow Catalytic Conv. and muffler system and am doing this buildup piecemeal

Thanks for any info you can provide

[Scott@USRT]

Quote, originally posted by bw_01jetta »

Hi Scott, I have a stock AZG MK4 2.0L and would like to replace the stock injectors/fuel rail with one of your aftermarket setups. I need to get a set of injectors that will work with the stock setup until I can get the new cam and lifters.

You absolutely should not replace your injectors with aftermarket parts unless you need to do so. If you go ahead and do it, anyway, you will need to invest in custom software so as to recalibrate the ECU. Without the software, you will run horribly rich, will certainly lose power, and may actually damage the engine. Don't do it! If you do add custom software, you'll simply be back to square one with no improvement made whatsoever.

This would be a foolhardy and fruitless endeavor. So, go about this sensibly and add your upgrade parts in balanced stages. Finally, if you're staying normally aspirated, there is no need at all for bigger injectors or a higher-capacity fuel rail.