RalliartRsX

jr_ss, if you are available, I am heading to JKTuning Tuesday for a redyno. I got a handle on the boost control issue and made a host of changes from the last time. I am hoping this time yields more positive results. I have to drop a new 12V power source for the Flex sensor, so will be bringing several gallons of E85 as well as doing a pump tune for the track. We will see how things shake out.

Car had the first track day Friday and performed well. I just wish all the heavy hitting machinery actually had some wheelers behind the wheel so I could learn a few more things.

S14rebuild

Luvn where this thread is going...good info and awsome popcorn fest!

RalliartRsX

Alot of the "good" info is based off of "invalid" assumptions outside of dyno graphs.....

I just read the first page. Another ridiculous and unfounded assumption....

The VE has the exact same VE (cylinder fill) as a standard DE head at 4000 rpm hahahahahhah! Have you even seen the flow numbers on a DE vs VE king? That is a grossly inaccurate assumptions and based off blind ignorance....

Goodluck to you king....you're gonna need it

jr_ss

I completely missed this...

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Kingtal0n

I guess nobody here understands what Volumetric efficiency is.

Flow rate has absolutely nothing to do with Volumetric Efficiency.
I don't know why you keep quoting flow rate like it has anything to do with torque lol.

I am not the idiot here. You just have no idea what VE means, or how an engine works.

I have proven beyond reasonable doubt that both DE and VE engines/heads have identical VE with my previous post (https://zilvia.net/f/showpost.php?p=...0&postcount=56) showing dyno graphs from both VE and DE engines which produce the same exact torque which = same exact VE.

Sorry but you need to learn more about engines before making these ridiculous posts.

Kingtal0n

You have no scientific background, and completely mis-using those terms.

VE head does flow more mass of air than a DE or DET head- I agree with that, the dynos I posted prove it many times over.

However
1. this does NOT change a cylinder's volumetric efficiency, or have anything to do with torque!

2. the VE head and DE head both achieve the same exact VE as evidenced by the most recent dynojets I posted.

3. Never try to compare a non-dynojet to a dynojet, it doesn't matter fwtq or rwtq or whatever. non-dynojet is BS and I can make then say whatever I want, there is no standard. No way to compare other cars. That is why dynojet is so powerful and revealing.


4. PV=nRT is an undergraduate equation created to simplify the true nature of gas molecules by using an 'ideal gas law' assumption - meaning if the gas was perfect and it's molecules occupy no volume and behaves ideally in a static NON-moving container/condition.

Which no gas ever does. PV=nRT does not include the terms for gas molecule size, gas molecule friction, gas harmonics/vibration/'waterhammer'/etc, and impurities such as water vapor (humidity), it does not include factors of flow rate. Its for examining gas in a balloon in a classroom, not a working moving engine. Don't ever bring it up on an automotive forum.


To eliminate any funny business with temperature, pressure, and volume, I used examples from naturally aspirated engine (identical Pressure) with the same sized engines (2L displacement Volume) at the same temperature range (50*F to 80*F Temperature). And they are all dynojets which utilize the same weight roller as a standard.

Here in this post we see that:
https://zilvia.net/f/showpost.php?p=...0&postcount=56

Further,
Because " not all engines are able to fill the same VE at the same RPM" I specifically chose PEAK TORQUE since that is where PEAK VE or 100% VE is likely to occur for ALL engines manufactured in the world with no exceptions. Whether 90% or 105% makes no difference; we understand intuitively that results will vary by 5 to 15% in general, due to altitude, temperature, humidity, drivetrain losses, tire composition friction, etc... so when we see an extra or missing 10ft*lbs of torque from each 2L engine at atmospheric pressure it still 'makes sense' because those differences are subtle/slight.

However, what you NEVER see, is a 2L engine making 50 or 60ft*lbs extra on a dynojet at atmospheric pressure. What we NEVER see, and is impossible to witness, is a 2L engine making 180 or 190ft*lbs of torque, using typical compression ratios and drivetrain parts on gasoline at sea level. It would ring "WARNING: IMPOSSIBLE". Because none of those variables we discussed can alter the torque that high, on a dynojet.


I'm sorry that I have more education and experience than everyone here. I hate it. But you guys are hard headed and refuse to look at all of the data I have provided and instead insist on living in a world where you make up the rules. And I don't make up the rules.

S14rebuild

This is why i log on.....

RalliartRsX

I'm an aerospace engineer by trade, with a masters.

I've interned at nasa and have worked on gas turbines for a few years.

Nope, not qualified at all lol.

I used that equation to simplify the discussion which I caveated above....

But meh you can continue to state as you wish....

RalliartRsX

Ps why are you comparing NA engines when the entire discussion and your dyno are all turbo engines?

Hahahahha!

RalliartRsX

Flow rate is in terms of cubic feet per min. The cubic feet is a volume. A volume has a specific mass associated with it like a box of air has a certain associated mass that is occupying the specific volume

The cross sectional flow area between the DE vs VE has changed enough where the VE head can flow more mass of air for a specific volume as due to the flow rate being higher, it can fill a specific volume (cylinder) with more air for a specific time (intake stroke). Hence why I state that a DE does NOT have the exact same VE at a given RPM peak RPM or whatever. The VE can fill the specific 0.5 liter volume at a much faster rate, and hence mass, than a DE during an intake stroke, which is a fixed constant.

If you are pouring water into a 2 liter glass, and you pour one at 2 l/sec and one at .5 l/sec do the glasses fill the exact same amount for a 2 sec pour? Because that's exactly what you are saying above....
The calculation for VE is
VE = (cfm x 3,456) / (c.i.d. x rpm)
So let me ask you this, if a DE flows say 100cfm @ 4000 rpm, and a VE.120, can you explain to me how both engines have the exact same VE if we are assuming 4000 rpm is peak torque or cylinder fill or whatever you call it?

But hey, if I have to extrapolate that idea, then maybe I give you more credit than I should....

jr_ss

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S14rebuild

Ohhhhhhhhhhhhhhh. This is getn good!!

RalliartRsX

Ps who the fuck is comparing dyno outside of king? Dyno can all be manipulated and then on the same breath, you like "nope, that dyno isnt right because. Lah blah blah"

So many assumptions, missteps and are sorts of nonsense and king continues to conflate like 100 different....things

RalliartRsX

So I really want to harp on this. And I am going to bolt the fuck out of this since king knows it all just for effect

Now, there is a much more nuanced equation which involves the ideal gas law, but for conversation sakes, since king thinks I am calling in an idiot because of his blind ignorance...

Spoiler alert; because you lack the understanding of a topic, DOES NOT mean you are an idiot. Another of your amazing leaps and assumptions....

RalliartRsX

Here is the more nuanced equation

m_dot is....FLOW RATE! Specifically mass flow rate......or in terms of an engine CFM.

RalliartRsX

Also, in the nuanced equation, you can see the ideas of a turbocharged engine unfolding and how it increases VE (temp rise due to compressing air, pressure drop or rise due to pressured air from the turbo's compressor)

I think I am done on this topic.......

S14rebuild

4 posts in a row...

jr_ss

But are you really...?

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