When will people learn engine config means nothing on output?

[OVERKILL]

Thx; I am currently researching it, have viewed several articles... but:
i) there's an intake snorkel for the cylinder head intake port that aims to reduce inlet losses evident with a sharp-edged inlet...

I think this bit varies depending on who is doing the test. I'm not an expert on this, just have used the data before when comparing heads and was aware that it's pretty standardized for the most part. This variability is why you'll find slightly different data for the same head. You'll often see "with pipe" or "no pipe", which indicates whether they've used a pipe designed to simulate an intake runner or not (and I assume an exhaust header if doing the exhaust side).

and presumably there is a similar snorkel that starts at bore diameter of the cyl head and presumably flares out a lot...

There's a cylinder bore adapter for various heads, you can see them under the accessories section of the product catalogue:

https://superflow.com/wp-content/uploads/2020/03/Flowbenches-2019.pdf

The idea is to simulate the bore the head would be fitted to.

then you start with air pressure measurement in the quiescent area outside of the inlet snorkel, and you adjust it to 14.696 PSIA... one std atmosphere, and you adjust the pressure of the outlet area (in a quiescent area) to 28" WC (just about 1.0 psi) LESS than the inlet pressure... to about 13.696 PSIA... and then you measure airflow at various lift values.

This sounds like a very manual setup, most of this stuff is automated with the SuperFlow units. Here's the manual for one:

https://superflow.com/wp-content/themes/SuperFlow2020/downloads/SF-750_Manual.pdf

The computer basically handles all of that once you set your parameters. So, for the 28" of water calibration, you just choose that in the software.

And yes, once the unit is setup, you repeat the test, each time changing the lift, to get the flow figures for each of the standard lift points, which are usually in 0.050" increments.

Do I have this more or less correct? Test pressure (inlet) 1.0 std atmospheres, delta P across cylinder head: 1.0 psi, meas in CFM (converted to std temp and press (STP).

Sounds like it, but I'm not an expert of running this stuff, I've just used the data previously.

Haven't thought about air temps, here.

The unit has both air temperature probes and barometric pressure sensors. Thus, all the results are corrected to a standard so they can be compared. I'd recommend reading section 7 (starts on Page 63) of the above manual, as it goes into FlowBench theory and mentions standardization (correction) if you are producing results designed to be compared broadly.

What, typically, are the two values given?

Well, the two I presented above are intake/exhaust, and just the peak numbers. There is usually a table, which, if one was feeling motivated, they could plot to get a flow curve.

 

[Cdn17Sport6MT]

Many thx, Overkill. I will read the info you referenced.

 

[clinebarger]

Well, while the Ford 1L I3 GTDI is a weezer(unless it’s in a Focus RS/Fiesta RS), the one Toyota is using in the GR Yaris in Japan and Europe is a screamer - and it has some commonality with their new Dynamic Force family. GM has managed to keep the pushrod alive and even rival the best from Europe for output. The RAV4 I’m renting now is surprisingly nice for a NA 2.5L I4 - it feels like a Toyota V6/V8 from the 1990s-early 2000s.

I’m sure Ford used the 2V OHV reasoning for the new 7.3L gasser V8 and it’s target application - box vans, school buses, paratransit vans and RVs built on E-series cutaway chassis and fleets who need diesel torque but no SCR/DEF/DPF nightmares. But isn’t Cummins using a 4V OHV layout for their 7-12L class engines?

Just about every diesel uses 4 valves per cylinder in the last 20 years, Cummins 5.9 went 24 Valve in '98, Duramax debuted in 2001, 6.0L Powerstroke in 2003.

 

[ZeeOSix]

Please for the love of all that is holy in the land of IC engines, the mechanical arrangement of the cylinders has almost ZERO effect on power/torque characteristics of the engine!!!!

The mechanical arrangement of the cylinders (ie: V4, I4, flat 4, etc) don't really matter, but the number of cylinders, the bore and stroke, and the number of valves, head design, and cam design certainly do.

The torque and HP curve depends on all of those factors (and some other more minor ones like intake and exhaust systems, tuning, etc), and the area under the HP curve and how the HP is shaped matters and reflects how the engine will behave from idle to redline. Ideal is a high value torque curve which will result in a nice linear HP curve through most of the RPM range.

Here's a 120° cross-plane 3-cly 847cc (51.7 cu-in) Yamaha XSR900. Bore x stroke is 3.07 x 2.33 in (pretty over square). Very flat T curve and therefore a very linear HP curve. Makes it fast and easy to ride. Dyno is rear wheel T and HP.

 

[Spyderman24_7]

I'd have to ask something similar as to when BITOG members will readily admit that oil is oil, it all does the same thing, bwahaha...

 

[Cujet]

Oh I don’t know, the gas turbine configuration seems to make the most power of all internal combustion designs.

i do think there is a pleasantness to certain designs that speaks to the soul. my V8 powered F150 is the slowest and the most thirsty out of the three trucks (others are ecoboost 3.5 and 2.7) but the V8 is by far more pleasant.

 

[nthach]

That said, I also think 3 cylinders sound much nicer than any 4 cylinder.

If we’re also taking motorcycles, Triumph made the I3 a thing. My ears aren’t acclimated to it but it’s a unique sound unlike a standard Japanese 2/4 but different than a Harley or a Ducati. Definitely not like the V-twin/quad setups from Honda or Suzuki either.

Sound is a critical piece of branding too.

 

[ZeeOSix]

Ford's DOHC 4-valve V8's have, historically, not been high winding if we look at the 5.4L fitted to the Navigator for example or even the 5.0L in the F-150. Mustang's were cammed to spin a bit higher. Same with the large Japanese DOHC V8's by Toyota and Nissan.

The Mustang guys do tunes that raise the redline up to around 7500, maybe 8000 max. Seen some crazy dyno charts of Coyotes with a supercharger and a tune putting out some nice linear HP. The heads can certainly breath well to keep the HP going at high RPM (example below). Even stock Coyotes have a pretty flat T curve and linear HP curve.

 

[OVERKILL]

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The Mustang guys do tunes that raise the redline up to around 7500, maybe 8000 max. Seen some crazy dyno charts of Coyotes with a supercharger fand tune putting out some nice linear HP. The heads can certainly breath well to keep the HP going at high RPM (example below). Even stock Coyotes have a pretty flat T curve and linear HP curve.

View attachment 106916

Yes, the Coyote heads are a lot better breathing than the old Modular DOHC heads.

 

[Slow Car Sport Mode]

Many thx, Overkill. I will read the info you referenced.

He's a good guy.

 

[nthach]

Isn’t the Ford Coyote 5.0 also using a flat-plane crank much like a Ferrari V8/12 for higher revs and more of a top-end bias than low-end torque like a cross-plane crank?

 

[K.Aoi]

Isn’t the Ford Coyote 5.0 also using a flat-plane crank much like a Ferrari V8/12 for higher revs and more of a top-end bias than low-end torque like a cross-plane crank?

No, that's only in the GT350 Mustang model. The regular 5.0 is a regular cross plane V8

 

[OVERKILL]

Isn’t the Ford Coyote 5.0 also using a flat-plane crank much like a Ferrari V8/12 for higher revs and more of a top-end bias than low-end torque like a cross-plane crank?

That's the 5.2L Voodoo engine.

 

[Chris142]

Interesting. So you are saying that a 200 cu in inline 6 with a heavy 3 ft long crankshaft will have the same hp and tq as a 200 cuin v6 with a short light crankshaft?

 

[Skippy722]

Interesting. So you are saying that a 200 cu in inline 6 with a heavy 3 ft long crankshaft will have the same hp and tq as a 200 cuin v6 with a short light crankshaft?

It’s possible. BMW was selling a naturally aspirated 3.0L I6 making 333hp and 269lb ft of torque in 2000. Most modern NA 3.6L v6’s top out around ~305-310HP with the same torque.

 

[CR94]

Contrary to stereotype, the highest-revving engine I ever had, by far, was a pushrod engine (see below), with its rated peak power at 6400 RPM. They were aluminum pushrods, though.

 

[john_pifer]

It’s possible. BMW was selling a naturally aspirated 3.0L I6 making 333hp and 269lb ft of torque in 2000. Most modern NA 3.6L v6’s top out around ~305-310HP with the same torque.

Wasn’t it a 3.2?

And, at what RPM was it making that horsepower?

What RPM does that modern 3.6L V6 make its max power?

 

[Skippy722]

Wasn’t it a 3.2?

And, at what RPM was it making that horsepower?

What RPM does that modern 3.6L V6 make its max power?

Whoops… yeah, 3.2L. Peak HP at 7,900rpm and peak torque at 4,900rpm.

The peak are just one part of the whole story though, the Pentastar 3.6L v6 for instance in a sedan makes peak torque at 4,800rpm and peak HP at 6,400rpm. But it’s making 90% of peak torque starting at 1,800rpm and holds that till 6,350rpm. Accordingly, the I6 in an E46 M3 is making 80% of peak torque starting at 2,000rpm and holds that all the way through till redline.

 

[doublebase]

I’d be curious to start looking into the new Toyota turbo Tundra engine because that’s quite a change for them. Turbos. I’ve run into a few owners, they all say it’s a fast truck. It’s got power.

I think just about any modern engine has a good deal of useable torque nowadays. Everything has come so far in the last 30 years...first the port injection, then that was refined/improved to the point it was basically flawless. Then direct injection...those growing pains and improvements. Dual systems. We went timing belts, then timing chains, variable valve timing, oil fed actuators, electric actuators.

But most - if not all - these engines outperform engines from 30 years ago. And it’s done with better fuel economy. Doesn’t matter if it’s a V6, in-line 4, V8. Transferse mounted/longitudinal. They deliver.

 

[wpod]

It again put simply is how the engine breaths camshaft, throttle body, intake manifold design intake and exhaust port configuration exhaust. The design dictates how the air/ fuel and exhaust flows the engine. A supercharged engine gets more air / fuel pushed through it than a natural aspirated engine.