Bean

iTrader: (1)

Not really. If it's DI then its a bigger stress on the fuel system. Other than the small supply of reliable, high-flow DI fuel pumps, DI engines can run high boost reliably.

The 335i motor for instance has been pushed pretty hard by the modder community and it is handling it just fine. Vishnu's own car makes 627whp on pump gas using a 6262 single and he's put some VERY hard miles on it. It's pretty common among the other single'd 335i cars out there

LexFather

Except the GS is now sportiest in class and stole GS/5 series styling. Except the GS has been BY FAR the most successful mid size luxury sedan from Asia.

But hey you are the same "person" that said in this very thread the Genesisis Lexus LS competition lol.

natnut

I thought the turbo inline 6 engines for the 535i and 335i were notorious for fuel pump failures and it's only recently that BMW fixed that problem?

Bean

iTrader: (1)

Yup. The fuel pump isn't the engine. That's part of the fuel system. And it's not just the N54, quite a few other DI motors have had fuel pump issues. The VW and Mazdaspeed3 people have trouble with them dying too; the MS3 people have trouble with them not supplying enough flow seemingly at random and grenade their engine. The BMW engines have tons of redundancy built-in and if the pump dies, it detects it very quickly.

The fuel pumps in question are not the internal tank fuel pumps. These are high-pressure motor-driven fuel pumps for the direct injection system. DI motors by nature, however, work much better with turbocharging than normal engines and the turbo does not stress the engine itself.

BNR34

iTrader: (1)

DI just lower the threshold of detonation, allowing higher boost pressure or compression ratio. It doesn't necessarily means it works better with turbocharging and it stress the engine just as much as turbo engine without DI, DI just allow better performance at the same stress level.

IS350jet

I beg to differ. Without question, turbo chargers do add stress to an engine.

Bean

iTrader: (1)

Exactly, which pushes efficiency higher than what you'd have with a non-DI motor. Hence it works better with turbocharging. Perhaps I should have worded 'there's more synergy'. Hi compression, hi boost engines have ENORMOUS powerbands. My 335i rivals the much larger V8s in powerband. Plenty of E85 folks hitting > 500 ft-lbs of torque early in the powerband running stock turbos. The difference is, around town I get 30mpg and 35+ on the highway. All without any funky gearing like a double overdrive or ultra tall final drives.

Beg to differ all you like. It's no more stress than the added air of increasing displacement or making a more aggressive cam profile. Airflow is Airflow. Period.

IS350jet

Forced air induction adds stress to an engine. That is an undisputable fact and I think nearly everybody on this board would agree with me.

Bean

iTrader: (1)

Forced air induction doesn't add more stress than adding the equivalent airflow in some other manner. Do you understand?

Adding a turbo kit to an N/A car DOES add stress to an engine. That's not what's being advocated here. That's a strawman at best.

What's better a DI 3.5L V6 N/A that makes 260hp or a modern DI 2.0L turbo I4 that makes 260hp. Which one has a bigger powerband? Which one experiences more stress? Which one gets better mileage?

Answer:
The turbo motor
Both experience generally about the same amount of stress
The turbo motor.

IS350jet

Your theory doesn't make sense. If adding a turbo to a N/A engine DOES, in fact, add stress, then why don't factory FI engines have stress from a turbo.
Before you answer with a response that car makers already reinforce the engines for FI cars, ask yourself why they do that. The answer is simple,
"factory FI engines are reinforced because manufactures know, beyond any shadow of a doubt, that FI creates stresses and other forces not found in a N/A engine".

Mr. Burns

I just can't stand Hyundai, they take other people's details, tweak it a bit and call it their own:




Now there are Elantra coupes and Velosters running around with Lexus mirrors. It's almost like a calculated effort on their part to destroy and delegitimize premium brands by knocking off their design elements and putting them on mainstream cars. There's a reason why Toyota itself doesn't put Lexus mirrors on Corollas.

Come up with your own **** it can't be that hard.

Hoovey689

iTrader: (16)

If a modern V6 with DI is making 260hp we have a problem

300+ or bust

spwolf

lol... turbo's add a lot of stress to the engine, as we can see by reinforcements needed and lower compression.