Who's doing what with the 2.0T FSI?

[6cylindakilla]

My shop sells APR hardware and software and personally I'm really happy with it.  I don't have any experiences with other brands of software, but I have a customer who just upgraded a 2007 GTI with APR, and his boss has a similar car with Revo. 

We've also done a few turbo back exhaust systems (I personally removed an exhaust from a car with less than 500 km). 

So, what's out there and what do you like?

- Dave.

[enginerd]

Im testing some FSI fuel pumps.

Here is the max power/Torque you can get from the stock fuel pump.
There are no "drop in" replacement pumps at this time.



Subtract ~12.5% for a manual tranny.

[fast_a2_20v]

My buddies shop has been building some cold air intakes for customers as they come in... 3" OD powdercoated aluminum, eliminating the oem airbox / maf housing. Hopefully the next one that comes through I'll be able to score some dyno results before and after because he finally just broke down and bought a dyno.

I on the other hand, at his request, am gearing up to produce 2.0FSI maf flanges, in case you guys are interested in making some CAI's as well or for larger maf housings (gasp- big turbo projects?)... Anyways here is what the first version looked like, Although it doesn't matter since this is a cnc mill, we have since voted to make the outside shape simpler for welding purposes (although this is damn fine looking if I must say so myself)...

These will seal perfectly with the OEM MAF and OEM rectangular O ring.



Haven't decided for sure a price or if they are even going to get made, just thought I'd share especially since I posted to see if there was interest and it was black HOLED on vortex.

[enginerd]

Good old vortex nazi's.

Honestly there is a significant limitation caused by the fuel pump and the injectors. With a limited supply of direct injection gasoline pumps of various sizes, there is a big stepping stone to overcome. Companies with the engineering expertise will be developing big turbo kits, however the "home brew" BT kit is a long ways away.

While I can't release specific details I know of 2 big turbo FSI cars running around with upgrades to the pump and injectors. It was a costly and time consuming process.

AS GDI is more accepted by OEM's, and when E85 vehicles start running GDI then we will see some OEM high flow pumps and injectors come to market. Till then I don't expect too many companies to offer BT forthe 2.0 FSI.

[fast_a2_20v]

Does anybody have any idea what the max rated rpm is on the pump?

[enginerd]

I ran the calculations for the spring force required and the acceleration forces on the piston/tappett assembly. At 3500 PRPM the peak force of acceleration is 142 newtons @ 3500 PRPM (7000 ERPM) The spring load is only 144 newtons. A valvetrain engineer woule be scared by that because the spring is almost overwhelmed, however a fuel pump engineer would take credit for the residual fuel pressure acting on the pumping element after TDC. Also there is the consideration that you won't have catastrophic valve to piston contact should you float the pump. There is some increased contact stress from impact loading, and added spring stresses to consider.

I have run a hitachi pump to 4000 ERPM, 120 bar, 100% delivery. It still had good delivery, however the problem lies at zero delivery and high rpm. (Simulated engine braking at 8000 ERPM with no delivery and low rail pressure) It is easy enough to design a higher rate valve spring to accomodate this condition.

[Don®]

Great post guys...I'm not entirely familiar with the new FSI motor but I have already learned a few things.

I have to agree with enginerd...Home cooked BT meals are far ways from anything tangiable except for the turbo, exhaust manifold etc...etc...

The BT market for this platform will be quite narrow and thus far only players I see are APR and VF Engineering.

[20V18Tnut]

Europeans already widely using OEM parts from other VW/Audi FSI higher powered motors. In the VW Power magazine I saw some turbo and fuel upgrades which are basically bolt-ons. Yeah, and dont forget the 300bhp Bugatti 2.0FSI motor: parts from it are costly but it's direct bolt-on and factory proved set-up.


With the total lack of adaptation maps, it is a tuner dream motor. Me envy...

BTW, Justin could you confirm that the pump is PMW solenoid controlled.

[fast_a2_20v]

That is definantly a little scarry on that spring force, although I have NO idea what kind of residual pressure your looking at so- pretty much I'm clueless there!

I guess that puts a couple questions in my head here so I can get a better handle on the situation- Might seem like dumb questions but I don't have an FSI so tough 

What is the ratio of pump rpm to crank rpm?

I'm just curious what pump rpm we are at on the graph you posted, it doesn't really show any signs of the flow slowing down as rpm's go up so I was curious if it can simply be turned faster, hence the origonal question.

Second, is there any room for a second pump 

[enginerd]

The pump is driven by the end of the intake camshaft so 1/2 crank speed. Picture a 3 lobe camshaft that moves a small piston up and down. It has a flat tappett and a bore to guide it all machined in the head. There is no way to add an additional pump in the head. 

options to increase output are a higher flow pump with a larger piston, or a new cam lobe design with higher lift. Neither are easy drop ins.  If bosch or hitachi come out with an E85 high flow pump with the same bolt pattern that woudl be an ideal solution.

Pump solenoid is NOT pwm controlled. It's a little confusing on how it operates, but basically there is a control valve that is normally open and allows fuel to flow into the pumping chamber when the piston retracts. During the pumping stroke the fuel flows backwards through this valve. The valve is powered to close, and then the pressure rises and fuel is delivered. A check valve on the outlet prevents backflow from the fuel rail. By adjusting the timing of this inlet valve closure the pump delivery can be controlled. Powering the valve early and you get full delivery powering it late and you spill most of the fuel back to the inlet. This is all done inside the ecu with closed loop feedback. Closure of thei valve is critical and requires precise equipemnt. Run of the mill standalone will not do.

The reason this is done is because pumping fuel at 1500+ psi creats alot of heat and you dont want to pump any more than you actually need. Also you can't restrict the inlet side because the fuel will vaporize under slight vacuum at elevated temperatures.


The graph I posted shows the torque/hp potential of the pump. As a positive displacement pump, the output is tied to the RPM. The problem really lies with the torque peak. Even at low rpm you cant get lots of torque because the pump delivers less fuel at low RPM.

Positive displacement pumps diesel or otherwise are specified in mm^3/rev or cc's/rev delivery rather than liters/hour like a typical drop in high flow pump. This sets the torque limit. You can get 300 whp from the FSI fuel system, it will just have to wait till higher RPM to occur. It would have a peak torque ~ 270 - 280 to the wheels, but at high rpm this can translate to good hp, just a weak low end by comparison to other fuel systems.

[fast_a2_20v]

Yea, I didn't realize that pump is driven off the camshaft, for whatever reason I thought it was driven on the timing belt or something, totally seperate from the cylinder head.

In that case, yea, those two options seem like the only two... Given that, I would say probably changing the lift on the cam would be the easiest way, if I'm reading that right it sounds like the bore of the pump is relatively fixed... Either case, your going to need more force on that (return?) spring to counter the higher acceration of the higher lift, or the larger mass of the bigger piston.

Short of reinventing the wheel, it definantly sounds like the e85 pump would be the way to go, or just pirate something off a future FSI model with a larger output pump.

Any pictures or cut away diagrams of the FSI pump / system so I can get a better idea of what it is we're on about here...

[enginerd]

Here is a picture of the assembly. Tappett not shown.

[fast_a2_20v]

I didn't see a picture...

BUT, I did just barely read in car & driver that a 280bhp version of the 2.0FSI is going to be released in the TT... Bigger pump possibly?

[enginerd]

you can get 280 bhp with this pump, Just no more than 300 lb ft.

sorry here's the pic.

[bobqzzi]

It is my understanding there are 2 different pumps- one larger than the other. GIAC specifies the large one for their chips.

Which did you test?

[enginerd]

I tested a B pump,  supposedly the low output pump, and I have also tested a "high output" european pump. The high output pump actually flowed less on the test bench.

Bore dimensions were exactly the same. Aside from the addition of a service pressure vent valve I could not find a difference. Perhaps the changes are to the response time on the high pressure control valve. I had to run pretty high amperage to get the max ouput from the pump.  It may be that the valve closure is better and therefore improves the delivery under transient conditions. I just adjusted the timing of valve closure to achieve the maximum output. I am unable to simulate an entire system with demands from the injectors, and rapid changes in demand from drop throttle and tip in. My test may be different than what the vehicle does, but it shows the physical limitation of the pump.

[Don®]

Great info Justin!