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Mustang's 5.0L engine more impressive than Ferrari V12? So says Engineering Explained

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A10 GT PP1 is a tad quicker than the SS and traps 2-3 higher mph in the 1/4 (more significant than the tenth of a second e.t. improvement IMO of 12.1 vs 12.2 sec). But, to be fair to the engines, as I'm sure you're aware, those GM engines are a different technology; cam in block rather than DOHC. Physically the GM LT1 6.2 liter is similar in size to the Gen 3 Coyote 5.0. Sure it makes a lot less power per liter, but due to the design they can stuff more liters in the same package size so the per liter power efficiency is less critical. Quantity over quality thing. They have a similar power output, but take a different route to get there, different characteristics (higher torque, lower revving, etc.). After having been a cam in block guy my whole life, the Gen 3 coyote changed my mind. I love this Gen 3 coyote engine.
Great points. It's true; in recent decades Ford and GM have diverged in their respective engine design philosophies. GM has stayed somewhat old school while Ford has been more technically advanced. But like you said, performance wise, very close. Good point about package size too.


The 2020 Corvette weighs 3,647 lbs, according to Car and Driver's test. That's a good reason to make the C8 Z06 NA again. The C6 Z06 was NA and about a hundred or so pounds lighter than the standard C6 Corvette, and about 200 lbs lighter than the C6 ZR1. Hopefully the new NA Z06 will be in the mid 3,500 lbs range in lieu of the C7 trend, where each trim step up gained more weight than the last.
Holy crap! 3,647?! I thought I was overestimating at 3,500, lol. That's surprising because the Vette has a significant amount of aluminum and carbon fiber so for it to weigh that much seems odd. But yeah, Z06's have always been streamlined so hopefully your 200 pound weight reduction comes to fruition.
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Bullitt0819

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I would speculate it’s because of change in the compression rate with valve timing. The 12:1 in the Mustang is not 12:1 all the time. If you consider 87 octane should not be used in an engine with more than 11.7:1 compression, there are some valve overlap tricks going on.

The BMEP should rise with the compression ratio to infinity.
This. There are two measures for CR: Static and Dynamic. Static can be calculated--like in this video--dynamic considers valve timing, lift and overlap. You can make a 15:1 static CR engine a 0:0 CR engine if you leave all intake and exhaust valves open all the time.
 

Zinc03svt

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Gen3’s are amazing value proposition. Mean little 307 ci motor.
 

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I want a 812. Dream car
 

Stranger706

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If you consider 87 octane should not be used in an engine with more than 11.7:1 compression, there are some valve overlap tricks going on..
Could you explain this please Im just curious. I mean I know higher compression requires higher octane but where does 11.7 come from. Thanks
 

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engineermike

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Ok here’s the data I’ve gathered. Green points are port injection and gray have GDI. The vertical axis is bmep in bar.

Note the expected trend of bmep increasing as compression ratio increases all the way up to 12.5. The highest point at 12/1 is of course the gen3 coyote. The highest point at 11/1 is the gen2 coyote. The top points at 12.5/1 are the naturally aspirated Porsche 3.4 and 3.8. At 13/1 it’s the Mazda skyactiv g, and finally at 13.6/1 is the Ferrari 812.

Note that bmep seems to fall off above 12.5/1 compression. Also note that nearly all GDI (gray points) also have variable valve timing.
30340BB0-B79B-4565-8115-F1250E900A6B.png
 

Idaho2018GTPremium

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Ok here’s the data I’ve gathered. Green points are port injection and gray have GDI. The vertical axis is bmep in bar.

Note the expected trend of bmep increasing as compression ratio increases all the way up to 12.5. The highest point at 12/1 is of course the gen3 coyote. The highest point at 11/1 is the gen2 coyote. The top points at 12.5/1 are the naturally aspirated Porsche 3.4 and 3.8. At 13/1 it’s the Mazda skyactiv g, and finally at 13.6/1 is the Ferrari 812.

Note that bmep seems to fall off above 12.5/1 compression. Also note that nearly all GDI (gray points) also have variable valve timing.
30340BB0-B79B-4565-8115-F1250E900A6B.png
Interesting data, but I don't think there's enough data points above 12.5:1 to come to that conclusion. The Mazda isn't going to be tuned for maximum torque output, it's tuned for efficiency, so the BMEP isn't going to be as high. The Ferrari V12...I don't have a solid theory on that yet. One thought is it may have something to do with the high rpm for hp part of the equation being more beneficial than maximum torque values at mid-range rpm levels.
 

engineermike

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I agree about the lack of data above 12.5. If you have any other examples I’d be happy to add them. There just don’t seem to be many out there.
 

engineermike

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... The Ferrari V12...I don't have a solid theory on that yet...
Interestingly, the Ferrari FF is also on the graph. It has an earlier version of the 812 engine. Compression ratio is 12.3/1 and bmep is 13.5 bar. As you can see, it’s well below par as compared to other engines in the 12.0-12.5/1 range including the coyote. Perhaps the intake runners are very short so midrange VE suffers, which would lower peak bmep.
 

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Dfeeds

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Interesting data, but I don't think there's enough data points above 12.5:1 to come to that conclusion. The Mazda isn't going to be tuned for maximum torque output, it's tuned for efficiency, so the BMEP isn't going to be as high. The Ferrari V12...I don't have a solid theory on that yet. One thought is it may have something to do with the high rpm for hp part of the equation being more beneficial than maximum torque values at mid-range rpm levels.
At a quick glance of the conversation, I'd say you may not be far off. Higher engine speeds will lose efficiency with advanced cam timing/higher CR. I could be talking out of my rear but I'd imagine more pistons would mean more overall force to compress a higher CR mixture than an engine with less pistons. Then take into consideration that the v12 also is a higher static CR and that could simply be it. The engineers at Ferrari may have just decided that the v12 is more efficient with more cam retard, at a similar engine speed, than the coyote. So the v12 is actually running a lower CR than the coyote for more of its power band. It could also have something to do with how quickly a vct system can react, itself. It's not instantaneous, so there's going to be a compromise somewhere in the power band.
 

Darkane

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Interestingly, the Ferrari FF is also on the graph. It has an earlier version of the 812 engine. Compression ratio is 12.3/1 and bmep is 13.5 bar. As you can see, it’s well below par as compared to other engines in the 12.0-12.5/1 range including the coyote. Perhaps the intake runners are very short so midrange VE suffers, which would lower peak bmep.
Since you seem interested in NA BEMP, use the highest torque/L, highest HP/L, and highest CR (production gas) created in the last 10 years.

the 4.5L in the speciale.
 

engineermike

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Since you seem interested in NA BEMP...
Actually I started the whole exercise to study forced induction bmep vs compression ratio and injection type. The common logic on this board is that thou shalt not lower the compression ratio of the coyote when adding forced induction. I disagree and the rest of my graph shows a strong correlation between lower compression ratio allowing higher bmep.

The mb cla45 is 8.6/1 and a bmep of 30 bar, while the f-150 3.5 eb is 10.5/1 and bmep is only 23 bar. That’s just two data points but the trend is consistent.
 
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engineermike

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...use the highest torque/L, highest HP/L, and highest CR (production gas) created in the last 10 years.

the 4.5L in the speciale.
I’ll add this one and thanks for the lead. However, interesting that the 458 compression ratio is 12.5/1 and the Speciale is 14.0/1 but they both have the same bmep. They mention the Speciale has “reworked” intake runners, which could mean shorter, and that would explain lower peak VE that would reduce bmep in spite of higher CR. This also would support what I said earlier about the 6.2-6.5 liter v12 low bmep numbers.
 

Darkane

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I’ll add this one and thanks for the lead. However, interesting that the 458 compression ratio is 12.5/1 and the Speciale is 14.0/1 but they both have the same bmep. They mention the Speciale has “reworked” intake runners, which could mean shorter, and that would explain lower peak VE that would reduce bmep in spite of higher CR. This also would support what I said earlier about the 6.2-6.5 liter v12 low bmep numbers.
The speciale also revolves quicker at 9400rpm, than the standard 4.5.
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