Well you know much more about this than I do, I really couldn't say about the crank or it's relation to resonance. Il'l bring up the subject with Brian next time I speak with him and see what he has to say about it. Although admittedly he might start talking over my head.. LOL

 

A flat plane crank has all the lobes in the same plane. It allows for higher crank speeds with less energy.

The entire rotating mass of the crank is all on the same plane.

It also changes the exhaust pulse timing such that they are in better balance. I have a whole sheet on this but I can't find it.

Have attached a photo of the flat plane crank, however.

 

+1 on the korean bbq....

 

Here's the info on the flat crank (plane) engines:



The key feature that distinguishes Ferrari's 4.3-liter V-8 from its cousins is a crankshaft with throws spaced at 180 degrees instead of the usual 90 degrees. The benefit of this approach, drawn from racing-engine practice, is a consistent 180 degrees of crankshaft rotation between the power pulses in each cylinder bank. (The intervals between power pulses in a 90-degree V-8 are syncopated, varying among 90, 180, and 270 degrees.) The extra space between the Ferrari's intake and exhaust surges facilitates tuning the manifolds for better breathing and greater power. It also yields a blood-boiling 8500-rpm battle cry that prompts involuntary reaches for one's wallet.
The major downside of a 180-degree crankshaft design is that there's no ready way to balance second-order shaking forces. That hardship is less of an issue in the Ferrari, because its engine is located behind the driver and is bolted securely to a transaxle that helps damp vibration.

The Alfa and the Maserati have their engines sited ahead of the c o c kpit, where commotions are more likely to excite the steering column and the floor surfaces. Furthermore, the Alfa's transaxle is at the opposite end of the, so it can't help damp vibration. Hence, in the interest of smoother, calmer power delivery, Alfa and Maserati's V-8s are both equipped with 90-degree crankshafts.

 

interesting info- have any idea what Porsche uses?

 

Any video yet?

 

Not yet, planning on later this week like Thurs / Fri.

 

Porsche uses a cross plane crank. Ferrari and one other Italian car, I forget which one, uses a flat plane.

 

Ferrari started using the flat plane with the 430.

Maserati does not.

So we don't have too many other choices and I doubt it's Lambo.

 

Tomorrow is dyno and video day!!

Anyone is welcome to come hang out in San Pedro and check out the action, will probably be gtting started around 3pm.

 

Gcalo- So I came across this bit of info- Thoughts?

Flat plane crank v-8's are mildly out of balance, and will vibrate. Racers couldn't care less about this, provided it doesn't damage anything, but it would tend to mitigate against you buying the car, so road cars tend to be cross-plane, leading to a smoother ride.

However, cross-plane cranks require more counterweights to spin smoothly, which equals rotating mass. Add mass, limit rev-ceiling and engine responsiveness. With today's capacity limited, naturally aspirated formulae, the limiting factor is getting oxygen into the engine, which is essentially limited by revs. So, a higher rev-limit can lead to a higher-power engine.

So, mass and inertia.

There's also a minor issue in the firing order of a cross-plane design, in that the order by bank is LRLLRLRR, which means the perfect exhaust system would have a cross-over from left to right for maximum power -

 

looking forward to the video.

 

Dyno chart and vids

Dyno testing was done at Church Automotive in San Pedro area, very professional outfit and they do things "by the book", all they do is dyno testing and performance tuning.

Temp in shop was 80.4 degrees, low humidity, all runs done within an hour with car allowed to cool off a bit between the stock pulls and AH pulls.
We did two pulls in each set (two with stock and two with AH pipes). Numbers were same on both pulls with stock and same on both pulls with AH.
Only mods on car for stock and AH pulls were KN intake and RSS plenum.

997 dyno, stock vs. AH pipes:



Here was my 996 run from awhile back, for comparison's sake (stock vs AH pipes):



I want to go back and do a couple of pulls without the RSS plenum, with stock mufflers and with AH pipes to see if there is a diff. If my 997 was pulling 273TQ and 313HP at the wheels with the stock mufflers, I'd like to know if removing the RSS will have impact.



HQ video: (Revving / Drive-off with AH mufflers)
http://www.youtube.com/watch?v=IQWueROnQh8&fmt=18
Vid is high-quality, if it stalls / buffers just rewind a bit then let play.

Here is a video closeup of the mufflers:
http://www.youtube.com/watch?v=AbU_1kSgbFk&fmt=18

Drive by, accel, decel etc:
http://www.youtube.com/watch?v=vsUnHvRMtFk&fmt=18
.
.

 

I really like the 20 inch wheels - they look better on the video then on your previous pics.

Is it just me or is there a "supercharger" type whir in the background noise?

...I am not sure what that is but my stock exhaust does not make that sound...

Your car looks awesome OBTW- I am thinkin I need some 20's after seeing that...does it drive any different with the 20's- a little less smooth perhaps???

 

Bro I'm telling you, some 20" chrome TA's on your ride would look SICK! - You'd have your chrome fix and then some!!

The "whir" noise is probably from the KN intake, some sounds get magnified on the video cam mic- Standing behind the car you really don't hear it very pronounced.
The AH pipes really give my pcar a kick in the a$$, 10tq and 8hp extra to the wheels makes a noticeable diff, particularly in the mid-range.
I have no idea if my dyno numbers are "good" compared to other 997 non-S with aftermarket exhaust, but it feels pretty fast. I'd LOVE it if others would post some dyno results of their systems before / after- This type of info seems kind of scarce.

Surprisingly, the 20's ride just as smooth as my 19's. The OD of the 20's with Conti tires is less than 1% larger than the 19's with PS2 tires (true +1 sizing). 60mph on the 19's = 60.8mph on the 20's.
There is no discernable ride difference in town, which was my initial concern as well. The roads here in LA are pretty bad.