EA888 rev limit

[Keehs360]

What does that even mean?

Dsg transmissions have this sort of crawl mode. It works up to 5mph iirc. This way you avoid stalling. In creep mode and in bumper to bumper traffic. Riding the brakes for a long time isn’t ideal for a dsg. Things get hot and things start slipping

 

[ChrisMk77]

If I was driving a manual I would have the clutch when stopped. Which in a DSG the equivalent would be keeping your foot on the brake hard enough to disengage the clutch.

What does that even mean?

Like you know that they are clutches and not a converter, if you drive a manual you let the clutch out firmly not a bunch of slipping

 

[ChrisMk77]

If you can master that manual, then driving cars with manuals is a cinch.

The Ford TW20 that was the big tractor we had was easier to shift without clutching when fully hot but you could never drive that transmission without letting out gear grind.

 

[JerseyDrew77]

The Ford TW20 that was the big tractor we had was easier to shift without clutching when fully hot but you could never drive that transmission without letting out gear grind.

Gear grind, I hate that f'ing sound. I tried teaching my wife to drive my car prior to upgrading the clutch, that way I wouldn't car if she destroyed the clutch, and the sounds coming from her shifts made me cringe. She just couldn't get the concept of pressing down the clutch FIRST before shifting.

 

[ChrisMk77]

Gear grind, I hate that f'ing sound. I tried teaching my wife to drive my car prior to upgrading the clutch, that way I wouldn't car if she destroyed the clutch, and the sounds coming from her shifts made me cringe. She just couldn't get the concept of pressing down the clutch FIRST before shifting.

Well its not bad as the gears are pretty much indestructable its that it will only engage at the exact right rpm so if you rush or force it at all its going to crunch.

 

[chillax]

3. Avoid sitting for long periods with the brake pedal depressed and the gearbox in Drive mode
For cars equipped with start & stop function this problem is negligible, but otherwise the practice of standing still with the box in the Drive and the foot on the brake is equivalent to sitting at a traffic light with the clutch depressed. In short, the pressure bearing will wear out quickly. If you anticipate spending a long time on the spot, it doesn’t hurt to put the box in Neutral (N).

From the Tekdeeps article, I thought if you press the brake fully down the clutch disengages? At drive-thrus I usually undo my seatbelt if it looks like the wait will be a while. When I am stopped with a foot on the brake an icon pops up on the center screen indicating start/stop won't activate (because I don't have my seatbelt on).

 

[loudspl]

So, back to somewhat on the original topic.....if the HPFP floats around 8K why would that be an issue if you can compensate for needed additional fuel with large port injectors? Say you **hypothetically** have a set of ID 1700x for port inj. + the brushless pump, wouldn't that support north of 800 wheel on E85?
Unless you'll need 8K + rpm for something with a 64mm+ inducer

 

[Hoon]

The one time I tried to buzz it over 8K the fuel pressure plummeted, it went lean and threw an HPFP code. The car was NOT happy.

It's expecting the pressure to be there. You can't just tune around the issue when about 50% of the fuel system capacity suddenly disappears. The ECU shits its pants.

 

[loudspl]

The one time I tried to buzz it over 8K the fuel pressure plummeted, it went lean and threw an HPFP code. The car was NOT happy.

It's expecting the pressure to be there. You can't just tune around the issue when about 50% of the fuel system capacity suddenly disappears. The ECU shits its pants.

....Switch to Syvecs and get extra fuel from port injection?
Seems like there's not much fuel able to go in at that high rpm anyway with DI due to very short injection window..

 

[Diggs24]

The one time I tried to buzz it over 8K the fuel pressure plummeted, it went lean and threw an HPFP code. The car was NOT happy.

It's expecting the pressure to be there. You can't just tune around the issue when about 50% of the fuel system capacity suddenly disappears. The ECU shits its pants.

You can tune around mechanical wastegate codes with eurodyne why not hpfp codes?

 

[PowerDemon]

....Switch to Syvecs and get extra fuel from port injection?
Seems like there's not much fuel able to go in at that high rpm anyway with DI due to very short injection window..

That would be the only way yes. But if you were going to pay the money for a Syvecs ECU you might as well get an RS3/TTRS. The DAZA motor is God’s gift to the world... Right after the LS.

 

[Hoon]

You can tune around mechanical wastegate codes with eurodyne why not hpfp codes?

The code itself isn't the problem. The fueling calculation becomes way fucked up and the car goes lean before the code.

....Switch to Syvecs and get extra fuel from port injection?
Seems like there's not much fuel able to go in at that high rpm anyway with DI due to very short injection window..

You'd have to eliminate the DI system and make dummy "injectors" out of solid metal.

You can't leave DI injectors in the cylinder with no fuel flow to cool them. They melt.

I'm sure you could find a spring (or maybe add an inner spring) that would prevent the HPFP from floating. That would be the best solution, but it's really a questionable endeavor because even when ported these heads are very inefficient at high rpm.

 

[scrllock]

For big power (which is presumably what you're after if you're going for some 8k+ rpm build), having DI is amazing for drivability as the larger PI injectors are not great at idle duty cycles. Hence why you now see R35s and other non-DI platforms running additional sets of PI injectors. On top of displacement, this is one of the big advantages the 2.5TFSI, Gen3 Coyote, and 5.2FSI platforms provide.

One of the big supra guys (Papadakis?) hit some early power records with the B58 by doing this DI-delete, but that's race motor stuff, not something you want on your street car.

Presumably you can modify the HPFP somehow, the 5.2FSI rev limit is quite high and allegedly is DI-heavy on load (though that's also dry-sumped and has those sick 07k heads).

 

[loudspl]

For big power (which is presumably what you're after if you're going for some 8k+ rpm build), having DI is amazing for drivability as the larger PI injectors are not great at idle duty cycles. Hence why you now see R35s and other non-DI platforms running additional sets of PI injectors. On top of displacement, this is one of the big advantages the 2.5TFSI, Gen3 Coyote, and 5.2FSI platforms provide.

One of the big supra guys (Papadakis?) hit some early power records with the B58 by doing this DI-delete, but that's race motor stuff, not something you want on your street car.

Presumably you can modify the HPFP somehow, the 5.2FSI rev limit is quite high and allegedly is DI-heavy on load (though that's also dry-sumped and has those sick 07k heads).

Maybe something like this would work. Good for 9.5K rpm, DLC coated, bigger piston:

https://www.bar-tek-tuning.com/high-pressure-pump-upgrade-bar-tek-5-2-l-tfsi-gen-2

And if not, maybe eliminate the DI somehow and raise the idle rpm in the tables so you can run big PI. Although it's probably not that simple..

 

[swcrow]

Gear grind, I hate that f'ing sound. I tried teaching my wife to drive my car prior to upgrading the clutch, that way I wouldn't car if she destroyed the clutch, and the sounds coming from her shifts made me cringe. She just couldn't get the concept of pressing down the clutch FIRST before shifting.

reading this made me cringe