Cam spec discussion

[Chewy1576]

Just refining the duration & LSA a little... and I am think out loud here, the HE351VE & Banshee controller can be programed to build boost near idle, so my thinking is that with near instant boost getting a load moving wouldn't be as labored as well as gear shifts with a manual tranny, I think I could get use to not getting a load moving if I could have excess power in the on road rpm area... I know a "towing" cam is normally for grunt from a standstill, I think I would prefer road speed performance more... not sure tho, just thinking here..

And I still think a faster opening ramp (fatter lobe) would give more flow at low lift of the valve, and a quicker closing ramp would help..

The below chart will have 3* of overlap @.050" lift
I'm using valve lift # of 480/490
Max ex lift @ 108* BTDC
Max in lift @ 102* ATDC

@.050 198/215 LSA 105

Exhaust Open: 36BBDC
Exhaust Centerline: 108BTDC
Exhaust Close: 1BTDC
Intake Open: 3ATDC
Intake Centerline: 102ATDC
Intake Close: 21ABDC
Exhaust Area: 32.7
Intake Area: 29.6
Exhaust/Intake Area Ratio: 1.1 : 1.0
Overlap: -4
Overlap Area: 0.0
Overlap/Total Area: 0.0%

I wish TPS signal was included in the Banshee, to allow for an open veins at idle, then close down as soon as TPS was above 0%. Additionally close the veins slightly under a big delta TPS to get exhaust gas velocity under acceleration as well.

That's the point of closing the veins right? To increase exhaust velocity through the turbine to drive it more quickly. The byproduct of that is drive pressure, which is relieved when the veins open as RPM and boost increases.

 

[Will L.]

I wish TPS signal was included in the Banshee, to allow for an open veins at idle, then close down as soon as TPS was above 0%. Additionally close the veins slightly under a big delta TPS to get exhaust gas velocity under acceleration as well.

That's the point of closing the veins right? To increase exhaust velocity through the turbine to drive it more quickly. The byproduct of that is drive pressure, which is relieved when the veins open as RPM and boost increases.

Not to derail thread but that’s why I don’t think it should be that hard to control a vvt at least at a basic level. Simple algorithm tps s boost equals vein position. If you have that then you could blow the exhaust valve ports wide open because dumping the entire cylinder out into a manifold/ header won’t matter on drive pressure- it will be choked down to what is needed better than a constant feed to the turbo.

Heat loss is the only other concern, but really that should improve. Piston all the way down power stroke. Then piston comes up and ex valve open pushing out. So large area into small as it goes through valve means hotter. Now it expands into manifold/ header which means slight cooling, until it hits the vein/wastegate and will be restricted again there Raising temp. Although every time there is a change of dimension, there is energy lost, that affects so little the instrument to record how little it is would cost more than 2 of our houses combined- so that won’t matter.

the easier that piston can expel the gases, the less resistance to its opposition cylinder on power stroke.

 

[Twisted Steel Performance]

I wish TPS signal was included in the Banshee, to allow for an open veins at idle, then close down as soon as TPS was above 0%. Additionally close the veins slightly under a big delta TPS to get exhaust gas velocity under acceleration as well.

That's the point of closing the veins right? To increase exhaust velocity through the turbine to drive it more quickly. The byproduct of that is drive pressure, which is relieved when the veins open as RPM and boost increases.

Have you talked to Dolan about this?

 

[Chewy1576]

Have you talked to Dolan about this?

Yes, he doesn't own the Banshee anymore so he won't support him make any more updates for his version.