wtf is a c1234?

[Luckrider]

Nah... I meant what RPM are you making full boost. I would guess that it is low based on the high torque numbers relative to the hp.

Edit: BTW, I am in class right now... can't watch that sadly.

[jamesm]

Originally Posted by Luckrider

Nah... I meant what RPM are you making full boost. I would guess that it is low based on the high torque numbers relative to the hp.

Edit: BTW, I am in class right now... can't watch that sadly.

lol no i mean 344 @ 11psi, 387 @15. the dyno didn't have a functioning rpm pickup so we couldn't get torque.

it spools 10psi by around 3300-3500rpm depending on load, high boost (15+) by 4k, again depending on load, what the boost target is, wastegate duty settings etc.

[Luckrider]

Ahhh.... okay. Boost threshold is higher than I originally thought then. Not bad, but I doubt you even broke 300 wtq.

Yep... Just did the math, if 387 is at 7k (totally reasonable to assume based on the stock cam profile) then TQ is 290. I am sure it is probably peaking at boost threshold closer to 4k and maybe just barely breaking 300. Still respectable for reasonable amounts of boost.

[jamesm]

Originally Posted by Luckrider

Ahhh.... okay. Boost threshold is higher than I originally thought then. Not bad, but I doubt you even broke 300 wtq.

Yep... Just did the math, if 387 is at 7k (totally reasonable to assume based on the stock cam profile) then TQ is 290. I am sure it is probably peaking at boost threshold closer to 4k and maybe just barely breaking 300. Still respectable for reasonable amounts of boost.

It peaked before 7k due to the boost tapering from the soft wastegate spring. More like 6-6.5k. You can see the chart at the end of the video. The run at 11psi held boost to redline and peaked above 7k.

The boost threshold is more a function of programming than anything else. It's not even targeting full boost until after 4krpm at higher boost levels. Targeting high boost before then just results in excessive stress on the engine (and wheelspin lol). I think at 1.8bar absolute target it's something like 4200rpm that I have it set to be at full boost now. When it was running an mbc it would make more boost much faster, but you certainly wouldn't be getting anywhere faster .

[Luckrider]

Originally Posted by jamesm

It peaked before 7k due to the boost tapering from the soft wastegate spring. More like 6-6.5k. You can see the chart at the end of the video. The run at 11psi held boost to redline and peaked above 7k.

The boost threshold is more a function of programming than anything else. It's not even targeting full boost until after 4krpm at higher boost levels. Targeting high boost before then just results in excessive stress on the engine (and wheelspin lol). I think at 1.8bar absolute target it's something like 4200rpm that I have it set to be at full boost now. When it was running an mbc it would make more boost much faster, but you certainly wouldn't be getting anywhere faster .

So basically you are using the EBCS to help keep building torque throughout the range. Makes sense.

[jamesm]

Originally Posted by Luckrider

So basically you are using the EBCS to help keep building torque throughout the range. Makes sense.

More to limit torque down low. The mbc is great for immediate boost, but immediate boost isn't great at 15psi on 225's . It's also not easy on the engine at all. Better to let things ramp up at a more reasonable pace. Keeps the car pointed straight lol.

[Luckrider]

Originally Posted by jamesm

More to limit torque down low. The mbc is great for immediate boost, but immediate boost isn't great at 15psi on 225's . It's also not easy on the engine at all. Better to let things ramp up at a more reasonable pace. Keeps the car pointed straight lol.

I agree on the ramp up, but come on, 225s? I am 90% set on 245/40R17 Square NA. Then again, this isn't FL and I can make use of the grip in the corners.

[jamesm]

Originally Posted by Luckrider

I agree on the ramp up, but come on, 225s? I am 90% set on 245/40R17 Square NA. Then again, this isn't FL and I can make use of the grip in the corners.

they're just burners. i'll throw 245's or 255's on there if i ever decide to stop doing burnouts. until then, i'd rather melt cheap rubber .