The 458 engine produces massive amounts of power at extremely high RPM's. Can anyone explain in layman's terms how the 458 does so? What engine characteristics determine its revvability. (Patent to be filed tomorrow on this word.) What is different between the 458's engine and the V8 in my E63 (that red lines and falls flat on its face at around 5-6K/min)??
All true, plus low reciprocating mass, low friction surfaces and a dry sump, which reduces pumping losses.
One thing not mentioned is the high compression ratio (12.5:1) Ferrari uses for their new engines along with specific piston design for more efficient combustion and of course the exhaust headers to improve air flow. Plus lots of dyno time to fine tune the specifications. On a more basic level the engine is very 'over square' ie. a large bore compared to a short piston stroke for the design. CH
To sum up what everyone said already, features that makes the 458 engine rev to 9k rpm: 1, Minimize weight of all moving parts (Flat plane crank, small piston from the small displacement, short stroke rod, lightweight valvetrain) 2, low friction surfaces from the small diameter pistons. 3, dry sump to reduce pumping losses. 4, breathing: high flow heads, equal length headers, high lift and duration camshaft profiles. Your E63 V8 have none of these features or the opposite of it. The 458's V8 is made for high revving peak power, but low torque. The E63 V8 is a low revving large displacement torque monster like all the American muscle car. There is nothing new on the 458's V8, the LFA's V10 have all identical features and similar power (except direct injection, that's why the lower specific output). Actually the S2000's engine is almost identical also from 10 years ago, it is just missing the latest direct injection and don't have the exotic dry sump and flat plane crank. The S2000 engine also rev to 9k rpm and have almost as much specific output of 120 hp per Liter (458 is 126 hp/L). The 458's engine is basically two S2000 engine mated together. Twice the displacement, twice the cylinder count, twice the power, sounds twice as cool and twice as fun.
Interesting reference to the S2000. Another example of a high winding road car engine is the 911 GT3. Yes, there is nothing magic about achieving those stratospheric RPMs, but it does take good execution and ... costs money. And more so as the size of the engine increases for the same number of cylinders because there is more mass to move.
Yes there are many example of similar high revving road car engine. The S2000 reference is fun because it is exactly half in everything of the 458's engine.
lets also not forget something very important in today's high end mills that spin so high. use of advanced coatings on engine internals has greatly improved the ability to rev very high AND mantain good engine life. industry standard today, which Ferrari (and LFA, which is slightly detuned in current form, 600+ horses to come) uses is DLC. There are many other techniques/coating substances used in motor racing, and super high end apps, but DLC has become viable in mass produced exotics like F cars...
Two S2000 engines (gen-1) are, arguably, closer to a F430/Scuderia's engine than a 458's...standard injection and closer in size/power. If my numbers are correct... Two S2000: 4.0L, 480hp, 120hp/L F430: 4.3L, 483hp, 112hp/L Scuderia: 4.3L, 503hp, 117hp/L 458: 4.5L, 562hp, 125hp/L Two Gen-2 S2000: 4.4L (actually 4.3L), 474-480hp, 108-109hp/L
Jeff, Writing the 458 have low torque is not correct, it has a very high torque peak in comparison to its displacement. The F136FB engine have 88,5 lbft per liter (120 Nm / liter) that is a fantastic results for a V8 revving up to 9200 rpm. The torque curve is almost flat from 3000 rpm, thanks to its four-mode variable-resonance intake manifold working in the 2500-6750 rpm range. For reference E63 AMG V8 71,3 lbft/liter Z06 67,1 lbft / liter The Honda F20C S2000 had 76,6 lbft per liter at very high rpm (7500) but did not have any sistem improving volumetric efficiency at low rpm. To be honest the 458's pure seven speed gearing permits to use shorter gear ratios almost fulling the gap with biggest displacement or Turbos in terms of ''torque at wheels''. Cheers Luque
Yes. And the short gearing allows the driver to stay in the high RPM power band. Pure driving enjoyment. As a rule of thumb, 1 lbft per cubic inch (62 lbft per liter) is considered "good" in a normally aspriated engine. Exceeding this by more than 40% is truly remarkable in a 4.5 liter engine capable of 9000 RPM while holding itself together at those stresses. The engine has always made the Ferrari and still does.
I agreed. But they are all pretty close in the same ballpark, +-10% due to the direct injection and slight variation in displacement.
Yes you are correct, the 458's F136FB does have very high specific peak torque, I was just comparing relatively. Large displacement engine always have more torque even though their specific torque output is lower. Btw, the engine in the NA E63 is one of the lower detuned variant of that engine, the highest tune AMG SLS GT makes 77.2 lbft/liter.
Bare with me on my pure mech engr view of cars.... Torque is what matters in an engine. HP=Torque X RPM/5252 All engines have HP=Torque @5252 rpm since HP is a calculation not a physical measurement Three major ways to make big HP happen via the generally flat torque curve: Big Displacement (longer stroke helps) makes more torque Forced Induction (Turbo or Supercharger) which increases effective displacement High RPM on otherwise low torque engines. The F458 engine makes a relatively low torque barely crossing 300 ft-lbs on this rear-wheel dyno but..... .... It winds up to stratospheric rpms letting this torque produce max HP at 8500rpm. This takes serious breathing, valve train, and reciprocating mass engineering. Truly an engineering master piece. Compare to a big displacement approach - Dodge Viper V10. It makes 400+ ft-lbs of torque just above idle but runs out of breathing and/or valve train just over 6000 rpm. Image Unavailable, Please Login Image Unavailable, Please Login
Just to add on the effect of forged induction... The Porsche 996 and 997 Turbo cars are well regarded for their performance despite a small 3.6liter displacement. They end up making one of the highest HP/Liter level in the world well over 100 hp/liter. Look at the torque curve below when the engine goes on boost EARLY in rpm range. The HP curve slope goes up drastically and this engine provides amazing output from 4000 rpm to its limit of 6500 or so - runs out of ability to move air in/out.... I owned three of this wonderful Porsche Turbo cars but JUST HAD TO MOVE UP TO THE F458!!!! Image Unavailable, Please Login
Does it also have anything like variable valve timing? Or not? I mean is it like the F50's engine .. 'fixed' valvetrain and with only the variable intake system ? Thank you.
The F136FB has VVT both for intake that exhaust valves, that system was previoulsy employed in F136E / F136 ED engine (F430/430 Scuderia) The intake and exaust variable geometry of the F50 was more simple in comparisons to that one on 458 (a open / close system trough a butterfly valve) Cheers Luque
Thank you. By any chance do you also know how the system works? I mean is it externally like the VANOS in the BMW's or internally like the Honda's VTEC series?
More similar to VANOS, it's a pure VVT system. The Honda's VTEC and derivates controls also valve lift and opening duration Luque
You are welcome. Basically the 458 engine doesn't need to change lift and opening time with a low and high rpm cam. The four stages variable geometry inlet manifold and VVT are able maximize ' cylinders filling ' in the 2500 rpm - 6750 rpm range also with high lift cam you need to achieve high power values up to 9000 rpm
