MSP volumetric efficiency

[Spooled]

Has anyone found an accurate number for the stock VE of the MSP version of the FS-DE? I am very interested in this, but have no way of figuring it out (I assume you need a flow bench or something).

 

[peepsalot]

I thought VE was just power over displacement or something.

 

[Spooled]

Possibly, but I'm not sure what the N/A VE is of the MSP engine. If it's power over displacement, what units? Is it torque or HP? It is crank or wheel? I'm really curious, because I actually have amny siutations where it's helpfull to know rather than guess.

 

[Spooled]

For reference, a lot of B-series Hondas are close to 90%. I'm sure that the FS-DE isn't close to that, though.

 

[BradC]

VE= (HP*792001.6)/AP*CR*CID*RPM

Max torque is where max VE is, so use that as your RPM (if your car was dyno'd). AP= atmospheric pressure, I am sure you can figure the rest. Found this on http://www.hotrodder.com/Z28_454/math.html ,
so don't yell at me if the math sucks, just trying to help.

 

[Spooled]

http://www.epi-eng.com/ET-VolEff.htm

 

[Spooled]

VE= (HP*792001.6)/AP*CR*CID*RPM

Max torque is where max VE is, so use that as your RPM (if your car was dyno'd). AP= atmospheric pressure, I am sure you can figure the rest. Found this on http://www.hotrodder.com/Z28_454/math.html ,
so don't yell at me if the math sucks, just trying to help.

cool, thanks.

 

[Spooled]

I'd like to see a graph of the VE of a stock FS-DE engine. I wonder if there is something that can measure the amount of air coming out of the exhaust without restricting it much. If you could do that on a dyno output a graph based on RPM, you could see where flow efficiency lacks.

 

[flat_black]

Flow efficiency lacks on the exhaust side, very obviously. If you look at the head, it's very noticible. The casting is a little iffy on the intake side, but it still flows pretty well.

The flow rates, according to Blake at Sunbelt, are as follows:

Intake: 183 cfm
Exhaust: 164 cfm

 

[flat_black]

Ahh, yes, I almost forgot; I also made these charts to indicate flow rate requirements at various levels of boost... It was a while ago, so I nearly lost them.

		Boost (PSI)
				
		0	5	10	15

	7	189.84	254.39	318.93	383.48
R	6	162.72	218.04	273.37	328.69
P	5	135.60	181.70	227.81	273.91
M	4	108.48	145.36	182.25	219.13
*	3	81.36	109.02	136.68	164.35
1	2	54.24	72.68	91.12	109.56
k	1	28.13	37.69	47.26	56.82

		1	1.34	1.68	2.02

		Pressure Multiplier

 

[Spooled]

flat, you are awesome!

 

[BlkZoomZoom]

My head flows alittle over 200 on intake and around 195 exhaust.... oh wait, you meant stock...not "stock appearing". lol

 

[Spooled]

My head flows alittle over 200 on intake and around 195 exhaust.... oh wait, you meant stock...not "stock appearing". lol

This is my jealous face (boom03)

 

[Spooled]

That best part about this chart is that you can see exactly why our engines drop off in power before 6k.

Ahh, yes, I almost forgot; I also made these charts to indicate flow rate requirements at various levels of boost... It was a while ago, so I nearly lost them.

		Boost (PSI)
 
		0	5	10	15
 
	7	189.84	254.39	318.93	383.48
R	6	162.72	218.04	273.37	328.69
P	5	135.60	181.70	227.81	273.91
M	4	108.48	145.36	182.25	219.13
*	3	81.36	109.02	136.68	164.35
1	2	54.24	72.68	91.12	109.56
k	1	28.13	37.69	47.26	56.82
 
		1	1.34	1.68	2.02
 
		Pressure Multiplier

 

[jeffmsp]

so are ports designed for low to midrange torque production rather then high end zing then right.

 

[BlkZoomZoom]

Yes, but are whole motor is designed around this. It works rather well I would say.

 

[flat_black]

Actually, look at the 0 boost range... It's designed to make full power between 0 and 7000 rpm... Which it can when it's N/A. I think it's mostly that the car wasn't designed specifically to have the turbo, and accordingly, it can't mantain boosted power at higher revs, due to the head and manifold design.

Though honestly, I did enjoy how the MSP drove; It felt very nice, and very strong through the middle range. =)

 

[TurfBurn]

Geometrically and mathematically our valves and valvetrain is setup correctly. The ports though had some "issues" and the match you have between your manifolds and ports on both sides are critical to flow. But by far the majority of the cost in my port and polish on my head was in getting the exhaust opened up to match my turbo manifold...

 

[Spooled]

so are ports designed for low to midrange torque production rather then high end zing then right.

Yep, that's usually what most non-performance oriented heads are designed to do. Unfortunately, Mazda didn't create a new head optimized for a turbocharger. They just slapped the ol' Protege head on and called it a day.

 

[Spooled]

Geometrically and mathematically our valves and valvetrain is setup correctly. The ports though had some "issues" and the match you have between your manifolds and ports on both sides are critical to flow. But by far the majority of the cost in my port and polish on my head was in getting the exhaust opened up to match my turbo manifold...

Did you do any before and after flow tests? I'd like to see what the difference was fro the port/polish job.