What are the advantages of Ferraris flat crank? Sure they sound cool and rev high but does it give instant torque and hp or other advantages such as exhaust pulsing and flow? Has Ferrari always used flat cranks since the beginning? Any other makers that use a flat crank?
this has been asked many times, here's a link to some engine guys discussing the question. http://www.eng-tips.com/viewthread.cfm?qid=63312
Your 328 has a flat crank, but your BB512 does not! The thing they (and I think all F) have in common is better-termed "alternate bank firing". In a 90 deg V8 block, a flat crank configuration produces this, but not in other block forms.
Well, don't believe the flat crank hype. What Erik and Steve say below is true. You can use flat plane cranks in most american race series but no one does because of the power losses. They even tried back in Pro Stock but basically gave up because they are slower. They are lighter though as that article says which is the reason that everyone tried them. Erik Koenig ____________________________________________________________ Quote: Originally Posted by t_newnes "well that is not entirely true. Flat cranks can actually make more power than a 90 degree crank and that is why the IRL uses them. The only problem with using one on an LS1 (which i would also like to try) is that they make their power with higher revs which a stock pushrod engine can barely get to but if you upgrade the valvetrain to make it lighter and use stiffer springs, then you could raise the rev limiter quite a bit and you would be more able to tap into the extra power you get from the flat crank. I am not too sure how good they would be on the street with stop and go driving but on the track they would kick butt! That is why the IRL uses them. also because they are more balanced then a 90 degree crank that also helps them rev higher." They are required to run 180 cranks in IRL otherwise they would not. They do not make more power. They make a different noise that Tony George and the promoters wanted in the IRL series so everyone HAS to run that design by the rules. Erik Koenig _________________________________________________________________ Flat crank I have a custom Crower billet Ferrari flat crank here for a special project I am working on. I thought it would help you folks visualize what Erik was talking about. The flat or 180 degree crankshaft for a V-8 looks identical to a four cylinder inline crankshaft. The 180 degree crankshaft is balanced independently of the rods and pistons, etc. just like an inline four or six (no bobweights). As Erik said, these cranks offer no improvement over a conventional 90 degree crankshaft in most applications. They do seem to work better with individual intake runners and only because the exhaust pulse tuning is better with even firing cycles per bank. Intake manifolds for the LS1 and most other V-8 engines were designed for a 90 degree crankshaft. Unless you have a lot of time and money to come up with an intake manifold that will work effectively with a 180 degree crankshaft you will loose power. Another problem area is the secondary imbalance with these cranks. Other than using a pair of balance shafts there is no easy way to get rid of the imbalance. Ferrari guys love the sound of the flat crank. Also, the only cams made are for a flat crank so I have no choice in the matter. I am taming down the secondary imbalance by using titanium rods and very light pistons in these engines. Steve Demirjian Race Engine Development Sponsor
Aren't the F1 V8s flat crank? I was pretty sure I read they were. The following is from http://www.autoracing1.com/htmfiles/2006/F1/0117BMWSauberLaunch2.asp, which turned up in a quick Google search. Don't have time for a more thorough search. >>Although the V8 with the now compulsory cylinder angle of 90 degrees may look like a sawn-off V10, technically it is an entirely separate concept with its own specific characteristics. The V8 has a distinct firing sequence and requires a fundamentally different crankshaft design. Whereas a 72-degree offset crankshaft was used in BMW’s V10 Formula One engine, V8 powerplants can feature crankshafts with either four throws spaced at 90 degrees or four throws spaced at 180 degrees. Standard production cars are fitted with 90-degree crankshaft variants due to their better dynamic attributes, but a 180-degree crankshaft is favoured in racing-car engine design. The improved performance this allows offsets the disadvantages in terms of dynamics.<< Sounds like they have the option to go either way and are choosing the flat crank. Gary
Only 8's and 4's have flat cranks. Strenght, alternate bank firing, exhaust sound, easier to manufacture. For example the cranks that are forged by ford are all flat cranks when first forged then they are twisted to arrive at 90 degree throws. Ferrari just whittles them out of billet and they are done so to speak.
