360 window sticker says 5 valves

Yes the 360 has 8 cylinders with 5 valves per cylinder. 3 intake and 2 exhaust if I recall correctly.

 

Yep, as MalibuGuy states, it's a 5 valve head/engine.

 

As appeared on 355!?

 

And ended with the 360. The F430 went back to 4 valves.

 

sadly.

Is this because of emissions? Would be kinda cool to see the car after the 458 have a 40 valve head again.

 

While the 430 has a good sound I still prefer the more melodious 360/355 5 valve set up. Theres a "smoothness" in them, while the 430 is a little more raucous and less sonorous of a note.
The Audi AHA/ATQ engines have a 5 valve design as well and they can make a surprisingly good sound with the right exhaust

 

After much work and several vehicle applications, the five valve head adapted from F1 practice was replaced by more efficient four valve heads in both the street and F1 cars. Something they tried which did not work as well as the traditional (introduced in 1914) four valves per cylinder. Four valves also simplify cam design. Look at the cam profiles on a 355 or 360 if you want to see for yourself how complicated a five valve camshaft is.

Taz
Terry Phillips

 

4 valves is a superior design.

The 5 valve head is a failed experiment that has assumed its rightful place on the trash heap of automotive ideas.

 

Don't hold back Brian.

Can you explain a little bit about why it's a "failed experiment" and why 4 is better?

Thanks,

DM

 

Lol!! Such a way with words!

 

Brian always calls a spade a spade!

 

Terry, not that I don't agree with you, but saying 5 valves is no good because it is too complicated is like saying overhead cams are too complicated. Ferrari has never abandoned a technology because it is too complicated. They just charge more to maintain it

 

Audi have stuck with 5V tech' for quite some time now.

 

Not to say I do not like the cars. I do and I think they are great cars and a good stepping stone in automotive technology.

All engineering designs are a compromise. Piston engine designers are constantly going back and forth trading breathing ability with combustion effinciency all the while trying to control the heat generated. You could write a good sized book giving examples of production motors and how those tried to balance and optimize those. The 5 valve breathed well but gave up some combustion efficiency to do so. It also required a head design that deprived the area around the seats much of the coolant required to control temps. It also brought about a situation with small valves with small stems and guides. The small sizes and the temps involved are big contributors to the valve guide wear issue of the 355. It was overcome but at an expense Ferrari tried to avoid. The heat issue does limit the power they can squeeze out of it.

It was not a bad design, its limitations were quickly reached and technology passed it by.

The 4 valve pent roof design breaths very well, even at low valve lifts and has shown itself to be capable of combustion efficiency unknown in other designs. It can be cooled very well and support a motor that makes a lot of HP, produce very low emissions and get good mileage, 4 very closely related traits. It is an old design and engineers keep coming back to it for good reason.

 

Brian, as usual thank you for the excellent post. You always have the right information.

 

Brian,

grazie.

Explained in a way that even I could understand.

dave

 

Brian, it's because of what you stated, the 5 valve head design does not develope a lot of torque at low RPM right? Yamaha's R1 motorcycle had a 5 valve head design and it was not very successful in racing because of the lack of torque at low rpms. They then went back to a 4 valve head design.

Jim

 

One of the tings most people don't realize is that, for the most part, the F355 and 360 heads are cooled by oil. At speed (that is: being pushed but not raced), the oil is around 260dF while the water is around 220dF, and thus 4 valves heads cooled by water makes for a cooler combustion chamber that is able to make more compression. Under race conditions, the oil is pushing 300dF while the water sticks near 230dF.

The F1 guys tried 5-valve heads and these heads never saw a single race, but were tested a dozen times or so. The heads breath well, but do not make up for their other inefficiencies.

 

J- The 4 valve application I mentioned in 1914 used double overhead cams and Ferrari used DOHCs with two valves from the 1950s. So DOHCs are not a good example of a complicated technology.

Like Brian said, been there, done that, discarded that. Like hairpin valve springs.

Taz
Terry Phillips

 

Ah, but Ferrari got beat by pushrod motors in the 60s. Pushrod engines are simpler, more compact, less maintenance, and they work very well. And I wouldn't have these timing belt services...


I think my sarcasm gets lost in the typing.

 

I like reading rifledriver's posts. Concise and to the point.

 

Pushrod motors have many advantages in some applications, the biggest being able to get lots of dsiplacement in a compact size. Not very good for high revs though NASCAR gets over 9K out of them. They certainly develop lots of torque.

Dave