Anyone know more about these engines?

[BillZ260]

On the way to a buddies house yesterday eve and a guy wailed by me in this...

 

http://images.google.com/imgres?imgurl=http://www.alohatoystore.com/images/Maserati-Spyder-GT-300x225.jpg&imgrefurl=http://www.alohatoystore.com/car-010.htm&h=225&w=300&sz=10&tbnid=d4YZFchxB8KiIM:&tbnh=83&tbnw=111&hl=en&ei=y6mFRIbnOoHUaYWKldYN&sig2=Zxedn2agF0xotaa_xNLGmA&start=1&prev=/images%3Fq%3Dmaserati%2Bconvertible%26svnum%3D10%26hl%3Den%26lr%3D%26safe%3Doff (CLICK ON THE MASERATI on the left)

 

It was brand new w/ no tags. The guy had the hazards on and was driving it like he stole it!

 

Anyway I really liked the exhaust note and was wondering if anyone knows anything about them. It was a definite V8 sound but, it sounded like two cyl's per bank were firing instead of alternating banks. I was wondering if it had a x-over exhaust or something else that would have added to this effect?

 

It sounded awesome!

[Guest ON3GO]

its a ferrari 360 modena engine.. V8 sexy sound

 

mike

[TheNeedForZ]

Better! it's 4300 c.c, Ferrari F430 engine?

 

They have single plane crank shaft so the exhaust pulses are evenly spaced unlike domestic cross plane crankshaft V8.

[BillZ260]

So the fire timing is pulsed instead of staggard? I guess i'll have to look at some pics to see what you mean. It definitly sounded different..

 

Didn't see any ferrari crank pics in a quick google... So single plane crank means 180 Deg between throws. Does that mean each piston is sitting on it's own journal, instead of like most others where you have apposing cyl's sitting on the same journal?

 

Are any other V engines designed this way? What's the advantage? Less harmonics? Surely not just cooler exhaust notes maybe? ha ha.

 

Thanks for the input guys! This is interesting.

[TheNeedForZ]

The exhaust is not pulsed, only the pulses are evenly spaced; with cross plane crank, some exhaust pulses overlap a bit so the sound is not that clean. Single plane v8 crankshaft too has the long rod journal with 2 rods on each. The advantage for SP crank is better exhaust sound, better scavenging, and lesser counter weight on the crank. The disadvantage is more vibration since it now shakes like two I4 engine without any balance shaft.

[BillZ260]

On the drive home I thought about it and could see what it looks like in my head.

 

Is that engine overhead cam? Does it have the same cam / crank ratio as others? If the crank is flat how do the power combustions overlap?

 

If there are descriptive articles or websites pleas point me there, i've looked and don't see anything obvious.

 

Thanks

[TheNeedForZ]

Hey you have 888 posts.

 

The flat plane crank does not create overlapping exhaust pulses, the regular cross plane crank does.

 

You know I;ve never seen a pic of it on the net but I knew about it in one Vizard's book called "how to build and modify chevrolet small-block v8 pistons, rods & crankshafts", it talks abit about flat cranks.

 

This is how a single plane v8 crank looks like

||___

...___||

||___

........||

 

This is how a four cylinder crank looks like

||___

...___||

...___

...___||

||

 

"||" are rod journals. The v8 is arranged left,right,left,right while the I4 is arranged left,right,right,left.

 

You can get custom make single plane crank for domestic V8 but I never looked into it so I don't know who can make them or how much.

[BillZ260]

Hey you have 888 posts.

 

Not anymore

 

Thanks for the insight guys, I'll keep looking when I get time. Pics will help

[BRAAP]

The easiest way to describe the sound and firing pulse differences between the single plane and dual plane V-8 cranks is this. Think of the American V-8, (dual plane cranks), as “four” V-twin engines on one crankshaft. Now think of the single plane V-8 crank, (Ferrari), as “two” inline four cylinder engines on one crankshaft. Every notice how Harley V-twins and American V-8s sound similar? Also, for anyone that has ever heard a Ferrari V-8 or any other single plane cranked V-8, how it sounds much like a high strung four cylinder… The revised firing order that accompanies a single plane V-8 crank gives the engine a BRAAP exhaust note vs the dual plane crank RUMBLE. The physical design of the crank is such that when you look down along the crank from the nose, the dual plane crank, the rod pins make a “+” (the crank throws are on two separate planes), where as the single plane is a “-“, (all the crank pins and main journals are on the same plane), hence the terms “dual plane” and “single plane”.

Also, the single plane crank carries with it the inherent annoying buzzyness that your typical inline four cylinder has. The larger the displacement, the more exaggerated this “buzziness” is. Has to do with 2nd, 3rd, or 4th order harmonics, I forget which, It’s been so long ago when I was researching single plane cranks for a personal V-8 project, (still want to build one…). I am not positive, but I’m pretty sure that a couple NASCAR teams even played with single plane cranks at some point in the mid to late 90’s. Benefits of the single plane crank at that level of performance is exhaust pulse tuning with out criss-crossing headers, i.e. standard style headers. Dual plane crank V-8’s can accomplish the same exhaust pulse tuning characteristics by using “180 degree” headers as used on the Ford GT-40 and I’ve even seen few Panteras running as well. These tend be very long primary tubes and depending on available real-estate under the bonnet can be quite ornate. The middle two cylinders of one bank pair up with the outer two cylinder of the opposing bank and vice versa. This made for some very intricate header designs as seen in the accompanying pictures.

I’ve been wanting to build a SBC using a single plane crank since the mid ‘90’s for one of my Z cars. I’m willing to tolerate the added buzzyness just to get that exhaust note. I can appreciate the domestic V-8 rumble, I’ve owned and built a couple V-8s Z cars, but that rumble just doesn’t stir my soul the same way a 6 cylinder, 12 cylinder, single plane V-8 or even a VERY high revving four cylinder, (sport bikes), do. Every time I hear a 6 cylinder, V-12 or a flat crank V-8 fire up, it sends a chill up and down my spine. Even after all these years building and tuning L-series Z cars, even firing off our own L-28 race car gives me goose bumps. The exhaust note is intoxicating and befitting a “sports car” in the pure sense of the word. Not too mention, at the stop light grand-prix, the unsuspecting victim will think it is a just a wimpy little import engine with that silky smooth exhaust note…

 

here are a couple articles with pictures touching on the 180 degree header design…

 

http://home.alltel.net/bsprowl/Exhaust/180FEHeaders.htm

 

http://www.ssheaders.com/header.htm

 

Here are some 180 degree headers…

 

BRAAAP….BRAAAAAAAAAAP….BRAAAaaaaaa…….

 

 

 

 

[TheNeedForZ]

Hey thanks for the pics. Are you marketing something like "The BRAAP Experience" of sorts?

[BillZ260]

GREAT EXPLANATION!!!

 

Thanks so much