[ChubbyWilly]

Is there anybody here running E20 or E25 on their N20 engines? I have BM3 and have been considering addidng some E85 to make a E20 or E25 mix for an upcoming local event just to try it out. Any benefits or cons?

[BunkerJ]

Originally Posted by ChubbyWilly

Is there anybody here running E20 or E25 on their N20 engines? I have BM3 and have been considering addidng some E85 to make a E20 or E25 mix for an upcoming local event just to try it out. Any benefits or cons?

I've ran E30 on my Stage 2 map after I upgraded the LPFP but didn't notice anything on the butt dyno. I'm sure it might help some but to what degree, I am unsure. Just be sure you don't stress your stock LPFP too much if you still have it stock.

[ChubbyWilly]

Originally Posted by BunkerJ

I've ran E30 on my Stage 2 map after I upgraded the LPFP but didn't notice anything on the butt dyno. I'm sure it might help some but to what degree, I am unsure. Just be sure you don't stress your stock LPFP too much if you still have it stock.

Cool in that case i'll just keep running 93 octane. Also getting walnut blasting done today. I know N20s are not really known for carbon build up but at 96k miles it's a good time to check.

[sspade]

Originally Posted by ChubbyWilly

Cool in that case i'll just keep running 93 octane. Also getting walnut blasting done today. I know N20s are not really known for carbon build up but at 96k miles it's a good time to check.

Post pics of your valves!

All direct injection motors are prone to carbon buildup.

[rjd_F30]

Originally Posted by sspade

Post pics of your valves!

All direct injection motors are prone to carbon buildup.

+100000

Would love to see some pics of the valves. Or at least ask whoever did it how they looked and let us know, as well as how many miles your car has.

[Billfitz]

Ethanol has less energy content than gas, so it's not gong to give better performance in and of itself. A higher ethanol content will raise octane, but that doesn't increase performance. Higher compression and turbo boost ratios increase performance. If they're high enough that you need a higher octane fuel to prevent pre-ignition then a higher octane fuel is called for, but if you use higher octane fuel when the engine can't make use of it chances are performance will be worse.

[BunkerJ]

Originally Posted by Billfitz

Ethanol has less energy content than gas, so it's not gong to give better performance in and of itself. A higher ethanol content will raise octane, but that doesn't increase performance. Higher compression and turbo boost ratios increase performance. If they're high enough that you need a higher octane fuel to prevent pre-ignition then a higher octane fuel is called for, but if you use higher octane fuel when the engine can't make use of it chances are performance will be worse.

I mean, performance is going to change based on whether or not the car takes advantage of it. Without a tune, it won't of course but that's not to say that the car won't see *some* performance. Ethanol does carry less energy but it does carry more oxygen and burns cooler. So long as you aren't pushing the octane over 100 in these cars, since they're only 10.2:1 comp, then you'll be fine.

[Billfitz]

If anything a car that's not tuned to need higher ethanol content fuel will suffer loss of power and fuel economy by using it.
https://www.bellperformance.com/blog...d-for-your-car

[ilivas]

Correct. Increasing octane without the tune to take advantage of it, will decrease performance.

[BunkerJ]

Originally Posted by ilivas

Correct. Increasing octane without the tune to take advantage of it, will decrease performance.

So you're saying I can't run 118OCT in my car?

[ilivas]

Originally Posted by BunkerJ

So you're saying I can't run 118OCT in my car?

Of course you can, just get tuned for it!

[BunkerJ]

Originally Posted by ilivas

Of course you can, just get tuned for it!

Nah, I kid. Only 10:1 comp here anyway, so it'd be pointless. I'll just stick to ethanol for now.

[ilivas]

Originally Posted by BunkerJ

Nah, I kid. Only 10:1 comp here anyway, so it'd be pointless. I'll just stick to ethanol for now.

You can always take advantage of higher octane. The only difference is that you will have to increase boost a bit more than if you had higher compression. Lower compression is generally more optimal on Forced Induction cars anyways since it reduces cylinder pressures and detonation under higher boost. The higher octane will also allow you to advance timing even more.

Another plus is that race gas like c16 is still gasoline and has a lower stoichmetric ratio than ethanol so you can get away with more power on a smaller fuel system. The only downside to c16 is the cost. Roughly $9/ gallon I believe.

If you’re trying to go max effort on the n26, VP c16 or q16 is definitely a good way to go. If I had a local bmw tuner here, I’d give it a shot to try and break the speed record.

[BunkerJ]

Originally Posted by ilivas

You can always take advantage of higher octane. The only difference is that you will have to increase boost a bit more than if you had higher compression. Lower compression is generally more optimal on Forced Induction cars anyways since it reduces cylinder pressures and detonation under higher boost. The higher octane will also allow you to advance timing even more.

Another plus is that race gas like c16 is still gasoline and has a lower stoichmetric ratio than ethanol so you can get away with more power on a smaller fuel system. The only downside to c16 is the cost. Roughly $9/ gallon I believe.

Yeah, this car can't handle that much more boost to further worsen my 118OCT strive. Lol.

I am shooting for around 350whp, so I'm thinking 22-23psi on E30 (or even a little higher) and just smoothen out the powerband a little bit to relieve that instant torque. Poor turbo can hand 30+ but cylinders can only take 24

Thankfully I landed a new position so 911/M will be happening later this year! 50PSI?

[BunkerJ]

Yeah, about $9.19 I think last time we filled up the M2.

[ilivas]

One thing I learned is that making more power on good high octane fuel is safer for the motor than less power on pump gas for sure.

[BunkerJ]

Originally Posted by ilivas

One thing I learned is that making more power on good high octane fuel is safer for the motor than less power on pump gas for sure.

Easily. Now if we could just do something about that price....

[rjd_F30]

Originally Posted by BunkerJ

Yeah, this car can't handle that much more boost to further worsen my 118OCT strive. Lol.

I am shooting for around 350whp, so I'm thinking 22-23psi on E30 (or even a little higher) and just smoothen out the powerband a little bit to relieve that instant torque. Poor turbo can hand 30+ but cylinders can only take 24

Thankfully I landed a new position so 911/M will be happening later this year! 50PSI?

Happy for you that you're upgrading, but dreading the day you leave our section of the forums lol

[BunkerJ]

Originally Posted by rjdnyy224

Happy for you that you're upgrading, but dreading the day you leave our section of the forums lol

I'll still be here! Hell, might even keep her honestly. Either way, even if I don't, I'll stay on here to help.

[rjd_F30]

Originally Posted by BunkerJ

I'll still be here! Hell, might even keep her honestly. Either way, even if I don't, I'll stay on here to help.

Oh nice! Not too many people care about the community enough to stick around after getting rid of the car lol. F30 track build once the M/Porsche comes!?

[BunkerJ]

Originally Posted by rjdnyy224

Oh nice! Not too many people care about the community enough to stick around after getting rid of the car lol. F30 track build once the M/Porsche comes!?

Lol. Maybe. Did see a built engine for 7k.