loads of camdriven fuel pump info!

AutoTechRD said:

First off, those of you that have encountered the dreaded fuel cut know that more fuel is needed at low to mid RPM. The factory pump is not capable of building the requested amount of fuel pressure necessary to feed increased boost at low RPM. Many of the tuners have masked this by starting the line pressure higher ( raised from ~110bar to ~130bar) before the engine/ turbo make their way up to fuel cut. Sometimes this allows the engine to accelerate past the known fuel cut scenarios before the fuel pressure drops low enough to trigger a fuel cut. As chip tuners get more aggressive with their fuel and boost maps near boost onset, this problem gets worse.
By increasing the volume of fuel displaced each cycle the pump makes (3 per 720 crank degrees), the pump is capable of pumping more fuel for a given RPM. For example, lets say that Brand X pump is capable of pumping 100cc/min. of fuel @ 3000RPM, and 200cc./min @ 6000RPM. The engine may only require 110cc. of fuel @ 3000, and 180cc @ 6000RPM. In the above situation, it's the lack of fuel volume @ 3000RPM that is the limit, because at 6000RPM the pump is capable of flowing 11% more fuel than needed. Let's say that Brand Y increased the displacement of the pump, and it's flow capacity goes up to 135cc/min @ 3000RPM, and 270cc. @ 6000RPM. That means that the upon installation of Brand Y's pump, the engine will be recieving all 110cc/min of fuel it requires, along with an extra ~23% excess. Now let's say the ECU is flashed with software that ups the boost in the midrange and tapers it down near stock levels @ 6000RPM. It is concievable that the engine would now require 130cc./min @ 3000RPM, and 190cc./min @ 6000RPM. With Brand X pump, the engine would definitely hit a fuel cut @ 3000RPM, but the pump would be capable of keeping up @ 6000RPM. Add Brand Y's fuel pump and the engine can take in all the fuel it requires, at 3000RPM, and 6000RPM. Now the dilema lies in increasing the volume of the pump enough to meet demands but not so much that the ECU controlled regulator/ bypass valve is outflowed.

Some pumps ( or kits) that will be coming to market have seals that are OEM, and some are high quality aftermarket seals. Both are acceptable. The tolerances inside the pumps are very tight, and care must be taken by whomever assembles the pump. Some pumps will be assembled by the company, some will come in kit form requiring (sp?) assembly. It is not a dificult task to assemble a pump. Assembly can be done with one socket, a lint free towel, and clean hands.(overly simplified, but after all, that's essentially all that is needed) For those that are not capable of, or afraid to assemble their pumps, I am sure the company manufacturing the pump will perform the assembly using your pump housing for a small charge.

Now on to the myth about quality vs. cost... Just because a product is less expensive, doesn't mean that it is not lower quality. Sometimes a company may be able to hold a tighter tolerance, and still charge less. Especially if the parts are "easy" for them to deal with. For example, the company that "fits" our pump parts, deals with tolerances 5 times more accurate than we require on these parts. To these guys, 25 millionths of an inch is a clearance (and 5 millionths tolerance) on some parts. So the fact that we have a tolerance of that same 25 millionths makes our parts "easy" for them. These same guys deal with parts very similar to ours every day of the year for the aerospace industry. I am sure that most of, or all the pumps that come to market will have no more clearance than the .0002" that the factory parts have. Some companies measure in metric, so let me tell you that 1 Micron is equal to a little over 39.37 millionths of an inch. So in essence (sp?) our tolerance is ~.635 Microns.

In short, the fuel pump won't increase the peak hp. capacity of stock turbo cars, but it will allow more aggressive tunes at lower RPM.

I think that's a pretty good start towards an education on the new FSI rail pumps that will be coming to market soon.

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Keith@APR said:

APR 2.0T FSI Fuel Pump

After many long hours of testing, APR’s Engineering Team has developed the final solution to FSI fueling. Even unmodified FSI engines can experience a temporary loss of fuel pressure due to inefficient delivery by the OEM FSI fuel pump. The APR 2.0T FSI Fuel Pump was designed to ensure consistent fuel pressure delivery and will support up to 520hp. The APR 2.0T FSI Fuel Pump requires engine management recalibration to allow for the increased size of the APR Fuel Pump to ensure flawless drivability and is included with your purchase. APR Stage 2 and Ko4 Turbocharger clients will be able to take advantage of increased horsepower and torque up to 25hp and 35lb ft with APR Fuel Pump specific engine management recalibrations.

Pricing is $1099 but as an introductory offer for Waterfest 13 you will save an additional 10% and pricing is $989!

Inventory of APR FSI Pumps is in stock and awaiting final assembly and quality inspection. Order now for the special pricing and you will receive one of the first pumps no later than August 24th.

To place your order, please contact your APR Distribution Network found here http://www.goapr.com/VW/dealer/locator.php or order at the APR Online Store http://www.goapr.com/ or call 800-680-7921

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BoostedSpd6 said:

ok first its a nice fuel pump dont get me wrong.. secondly its fricken expenisve though and im one for saving money. and third how r u going to get that around the dealership since its camdriven (is it visble or hidden??) if anything goes wrong with ur car.. atleast with the walbro i have the dealership wont even see it.

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Haltech said:

Very good work my friend! Expensive but if it allows us to hit 400+, its all good.

Does anyone know how to relieve the stock fuel systems pressure?

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BoostedSpd6 said:

so ok lets say u buy this 900 some odd dollar pump and put it on... what about the pump in the fuel tank.. that one is only good to a certain point... can it keep up with the one under the hood. or are u gonna have to upgrade both of them... im just saying i solved the problem i think with the one in the tank... who knows if the stock camdriven one under the hood which by the way is the same as the EVO 9's fuel pump under its hood will do well with the walbro one in the tank on the ATP kit... in my opinion the one in the gas tank needs to be replaced first.. cuz from what ive been hearing the stock one under the hood is pretty damn good..

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BoostedSpd6 said:

my mistake i just heard it from someone. only implying what i heard about the evo thing. but in a sense i think i solved the one in the gas tank issue and now with all this knowledge im learning about the camdriven one its gonna suck to have to replace both of them.. how much can the camdriven one handle if im delivering it more fuel with a walbro. like horsepower numbers i dont have any data logged stuff but im wondering can i go over 315 with the walbro on stock camdriven?

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mrlilguy157 said:

perhaps you can. but i dont think so. through CP-E's diagnostics and what not, the reason the 315whp mark can't be surpassed is because the camdriven pump, hence why there is such commotion about it. i believe its getting enough fuel to the camdriven pump, but its having problems pressurizing and pushing out so much fuel into the motor at such a high flow rate. remember, it has to work more effeciently and faster and faster as the car wants to accelerate faster and faster

if you read the vwvortex threads, they vw/audi FSI motors are stuck at 300whp ish too, so i'm thinking they're the same pumps and we can use the APR pump, but thats the issue. APR is trying to work out a core exchange program and or a send it in and have a week turn around time too, but nothing's been finalized yet. that would make the pump upgrade about 400-500$ instead of a thousand.

the cost to upgrade this fueling system really isn't outrageous compared to regular fuel injected motors. remember, BT guys are havent to go through intank or inline fuelpumps (like the walboro 255lph), fuel pressure regulators, high flow fuel rails, and injectors, at about $100 a piece for nice spray patterened 600cc (at 4.5bar) injectors.

that exquates to about 700$, so the DI may be the same overall cost (with pending mailin upgrade or core exchange) or less; its just a different fuel system to upgrade. we'll never have to upgrade injectors. at 350+ crank HP and only flowing 25% their capacity, that safely equates to at least 700hp at maybe a 60-70% duty cycle.

don't be too quick to judge. everything about this new design of motors must be taken with an open mind. the only problem i see now is.... the fact that APR states the ECU tune will have to be adjusted for the new camdriven fuel pump. maybe CP-E's standback can adjust that? or hopefully Cobb's AccessPort? We can only wait and see. Its one step at a time.

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BoostedSpd6 said:

are injectors are only running 25% duty cycle..holy s***.. thats amazing considering i have alot of friends who have to replace there injectors if they want to upgrade thier turbos like DSM's and such. hopefully this crap gets figured out soon man and i hope the price comes down but i guess when u look at what others have to do to replace their fuel systems to go higher in HP ours isnt too bad. and u bring up a good point with Cp-e's EMS being able to adjust it or not i guess its a good thing im not buying any of this stuff till spring, hopefully itll all be figured out by then.

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mrlilguy157 said:

yes sir 25%. i believe thats cause the injectors for direct injection are CRAZY expensive to replace because of high pressures, but honestly i have no clue. port injection and direct injection are like apples and footballs. completely different.

not even apples and oranges, cause those are both fruits

its not a bad idea to wait at all.... i'm still debating for big turbo or mailing my k04 to new jersey to be bored/honed/polished/reworked for a little bit higher numbers....

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skylinemonster said:

May I ask where you are sending your K04 to in new jersey? I am very interested in getting my K04 reworked for more flow. Especially since I have not heard any updates on CP-E's hitachi/warner hybrid setup. Also, how long does it take and how much does something like that cost? Oh, one more quick question as well, would it be safe to say that the weak turbo seal issue that has plagued the ms6's K04s with billowing smoke seen by satellite <--[exaggeration, but not far off ] would also be addressed on a rework bore/hone job?

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TX Speed 6 said:

Ok, before you laugh at me.... I'm pretty clueless when it comes to fuel pumps/turbos/anything besides intake exh and other basics...

So i just learned that the new Sky Redline (so i assume solstice gxp) is direct injected and got this little bit of info on its fuel pump:

Direct injection requires higher fuel pressure than conventional fuel-injected engines, and an engine-driven high-pressure fuel pump is used to supply up to 2,250 psi (155 bar) of pressure. The system regulates lower fuel pressure at idle approximately 752 psi (50 bar) and higher pressure at wide-open throttle. The cam-driven high-pressure pumps works in conjunction with a conventional fuel tank-mounted supply pump.

So maybe we can look through some of the GM forums as well to see if maybe they might be getting anywhere. I know there cars are just as new to direct injection if not newer, but I would say the sky and solstice are probably getting more attention from the aftermarket than we are???

Ok, now (flame2) go for it

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