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Exotic "SOUNDING", high revving V8! Read "ENTIRE" thread before posting!!!


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This is the sound you want out of a V8

http://www.youtube.com/watch?v=J8t8kHWkRFo

 

(after watching that vid again, full body chill....) sbav.gifYES!!!! :2thumbs: We want our V-8 to sound like the V-8 in THAT video! love.gif

 

We know how they did it, (documented in this thread), now we need to duplicate it ourselves!!!! frankie.gif Muhahahah ahahaha .....

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So is there a way to make a custom crankshaft say for a Ls1?

 

Yes, there are a few ways. I’ll line out what I feel would be the simplest, least expensive bolt-in process which would apply to all domestic V-8’s, (this could even apply to other V-8’s)

 

1) Source a single plane crank.

. a) Build it from scratch out of billet steel.

. b) Have one of a handful of crankshaft manufactures build it to OE dimensions, though in single plane instead of traditional dual plane.

 

2) Contact a major cam manufactures and have them grind your favorite cam specs, but with the revised firing order, (revised single plane firing orders are listed below for Gen-I/II and LS-x SBC, and SBF).

 

3) Assemble your engine just as you would any other typical SBC, SBF, LS-x, headers, ignition etc, though for the intake, use some form of single plane intake manifold or Multi Port EFI manifold, i.e. NOT a dual plane manifold, and be sure you have now routed your plug wires for the “new” firing order. Add oil, turn key and enjoy….

 

Ok, in that scenario, for minimal out lay in cash, (compared to other options), you would have the “braaaaaaap” sound of a Ferrari V-8, with an engine that is “buzzy” feeling like a big displacement 4 cylinder , (think Volvo B23, etc), though the engine would still “perform” very much like a traditional stock cranked domestic V-8 with that same cam, induction, etc, including the same RPM range.

 

Ferrari’s, like that 360 Modena in the video above, rev to an 8500 RPM Redline, so keep that in mind if/when you build your flat plane crank SBC/SBF. With similar mufflers, it will sound the same as the Ferrari, just not rev as high, unless you build the engine with uber exotic NASCAR technology and valve train components, or, as discussed previously in this thread with a custom ultra short stroke crank, though valve train for a mega RPM domestic V-8 would need to be sorted out, more than likely quite expensive as "street driven" pushrod valve trains are not really conducive to lots of RPM without lots of tech and money thrown at them.

 

And for those interested, here is the Ferrari “firing pattern” transposed to SBC/LS-x and SBF engines utilizing “mirror image” single plane crank, as used by Ferrari, Formula-1, and IRL/indy league single plane V-8’s...

 

SBC and LSx

Cylinder numbering;

-2-4-6-8

1-3-5-7

Single plane Chev firing order of; 1-8-5-4-7-2-3-6

 

SBF

Cylinder number;

1-2-3-4

-5-6-7-8

Single plane Ford firing order; 1-8-3-6-4-5-2-7

 

When I was referring to “mirror image” single plane cranks, this picture shows the two options for a single plane crank design. The mirror image crank, in green has less “couple” induced vibrations the than other blue style;

 

CrankpinsCustom.jpg

 

This tire picture shows couple induced vibration;

 

D5336T07.jpg

 

 

 

Crank manufactures that can and will build you any crankshaft in any configuration and any specs;

 

SCAT http://www.scatcrankshafts.com/index.htm

EAGLE http://www.eaglerod.com/

Bryant

Cola

 

 

And there are few others.

 

Custom3.jpg

 

 

Ferrari 360 Modena V-8 engine…

800px-360engine.jpg

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I wish someone would just manufacture and sell this kind of stuff, instead of it having to be all custom order. I'm sure if you made a single plane crank package (cam, head, crank, etc) people would buy it if you market it as "Ferarri sound" or whatever.

 

:lmao: Patience grasshopper… the lights are on at Skunk Works… :wink:

 

 

Do keep in mind, such a “kit” will come at a financial cost far exceeding the power it will produce as compared to traditionally built V-8’s, just to have that exhaust note.

 

I believe there is a market here, though how large of a market that is actual willing to pony up the money it requires to do this, all for an exhaust note?...

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I wish someone would just manufacture and sell this kind of stuff, instead of it having to be all custom order. I'm sure if you made a single plane crank package (cam, head, crank, etc) people would buy it if you market it as "Ferarri sound" or whatever.

How much of a market is out there for such a kit?

A kit with a crankshaft, rods, pistons, cam, upgraded valvetrain, misc parts, etc... would cost quite a bit to manufacture.

Big time companies have showed their dis-interest in producing V8 flat-plane cranks.

It would be cool though. Especially in a Z!

 

I read on a forum that Scat refused to make a flat plane V8 crank for someone because it would have "too much vibration".

 

Vibration for a flat-plane V8 is 60% more than a standard inline 4 cylinder engine.

 

*edit*

DOH!

BRAAP got to it first!

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I'm kinda sick of this vibration talk, even though I know it's true and we're just sharing facts here.

 

The reality is that ferarri, lambo and the likes figured it out, so it's doable. Lets find out why.

 

That mini hyabusa based V8 isn't 90 degrees, maybe vibration is a part of that? I know he mentioned that it was also done for size reasons, making the V8 as narrow as a I4 motor.

 

I also can't imagine the vibrations being THAT bad. I mean, I almost dislike how smooth modern motors are. I'm so happy to be driving a Z again, and being able to feel the pulses of ignition through my veins.

 

I also don't understand why you'd need an all new bottom end like olderthanme is saying. I see no reason a company couldn't make a flat plane crank to use the existing conrods and pistons of a SBC, SBF, LSx, etc.

 

I think the key to keeping vibration to a minimul will be the least amount of rotating mass as you can muster (one of the reasons exotic motors rev soooo fast). Another way to lesson the vibration is to keep the idle high and move the rev range up. This means we can proably through out most of the larger displacement motors like big blocks.

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What I am wondering is how the externally balanced setup like the Fords would work. Why is there a 50oz weight on the flywheel... does the harmonic balancer have a 50oz weight offsetting it, or is the crank machined out of balance to be counteracted by the flywheel. Whats the point?

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I'm kinda sick of this vibration talk, even though I know it's true and we're just sharing facts here.

 

I also can't imagine the vibrations being THAT bad. I mean, I almost dislike how smooth modern motors are. I'm so happy to be driving a Z again, and being able to feel the pulses of ignition through my veins.

 

I also don't understand why you'd need an all new bottom end like olderthanme is saying. I see no reason a company couldn't make a flat plane crank to use the existing conrods and pistons of a SBC, SBF, LSx, etc.

 

I think the key to keeping vibration to a minimul will be the least amount of rotating mass as you can muster (one of the reasons exotic motors rev soooo fast). Another way to lesson the vibration is to keep the idle high and move the rev range up. This means we can proably through out most of the larger displacement motors like big blocks.

 

I'm not saying that converting a standard V8 is a bad idea...

It CAN be done with many off-the-shelf parts.

 

Personally, my Z car passion is to have them for racing and driving for sport. I wouldn't mind having an engine that vibrates that much. But for someone that has their Z for daily driving may not enjoy the vibration. Also with the engine in front of the driver, vibrations seem greater than if the engine is placed behind the driver (ala most Ferrari flat-plane V8 cars).

 

The more stroke that the engine has the more it will vibrate. I consider the reasonable max displacement for a flat-plane V8 to be under five liters. With most domestic V8 engines this means a very short stroke unless you are using a small block variety engine.

 

 

There is a reason you don't see many 4 cylinder engines over 2.4 liters and I think that vibration is the reason. A V8 is the same but double the displacement.

My Dad's 2.5 liter I4 turbo Porsche has some serious idling vibration which is normal but once driving the vibration disappears.

A raised idle would help the low-RPM vibration a good bit.

 

OTM

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Given the limitations of a pushrod engine with high RPMs, how about the modular 4.6 Ford motor? Yes, it is a larger engine with the OHC's, but would it not be able to rev up a lot higher?

 

How about destroking a motor? Would that help with the vibrations? Torque would be lost, but how is the correlation between the two? The 4.6 is 90.2x90, and the F360 had 85x79.

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I think it comes down to a lot more than just bore and stroke, but I could be wrong. After all remember the 5.0L Ford has a SMALLER stroke than the 4.6L and the F360. 76mm stroke and 101.6mm bore. It really is in the heads/cams and the R/S combination from what I hear. I have heard rumors of Coates reaching 13,000+ rpm with their CSRV heads on a built SBF - but those could be just rumors.

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This isn't a V8, but I'm sure it offers all of that glorious ferrari sound:

 

http://cgi.ebay.com/ebaymotors/FERRARI-206-DINO-V-6-ENGINE_W0QQcmdZViewItemQQcategoryZ119133QQihZ006QQitemZ160217676650QQrdZ1QQsspagenameZWDVW

 

That'd be a lot cheaper and easier than having a custom crank made and then getting it to rev in the right range.

 

There's a couple of the flat 12 ferrari motors on ebay, not very expensive imo, though I'm sure they won't fit in a Z without tubing the front end. (just a guess though)

 

Then there's a real deal...

 

http://cgi.ebay.com/ebaymotors/Ferrari-355-engine-F355-V8-3-5L-only-8-000-Miles_W0QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247QQcategoryZ33615QQihZ013QQitemZ230212978147QQrdZ1QQsspagenameZWD1V

 

I have to admit... I think it might be possible to get a flat plane setup built for a cheap motor that would cost less than that motor, and would mean easily replacable parts.

 

Idealy you'd do this with a OHC V8, so that it can be made to rev higher safer. So who wants to do a group buy for flat plane cranks for a:

 

1UZ

VH45

Mod Motor

Or something else?

 

I myself am just joking of course. I don't have that kind of money.

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What about the modular Ford V8? All you would need is the crank and rods to lower the stroke and you have a engine that can easily rev to 8500 RPM and have the sound of the Italian V8's. But with the parts availability of the Americans.

 

 

Plus a FLAT PLANE CRANK and cams to match:ugg:.

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Here is what you need to do!

http://www.fiero.nl/forum/Forum2/HTML/065545.html

I thought about doing something simillar, I was thinking of flipping them so I would get the real look of a v8, Link them both to some sort of frame, have a shaft passing in the middle of both, each engine would be connected to the shaft by a chain, you could then connect the shaft to a normal transmission. That would take a lot of fabrication. This guy did it much more simply althout I dont know how the transmission are holding up. If you want even more of an exotic sound take two of those, http://cgi.ebay.ca/Arctic-Cat-1000-Triple-Engine-Complete-Thundercat_W0QQitemZ220217100007QQihZ012QQcategoryZ100468QQrdZ1QQssPageNameZWD1VQQ_trksidZp1638.m118.l1247QQcmdZViewItem put a chopper style belt on each end, with a shaft in the middle as I said, would be even simpler, and it would sound really brutal. But would probably be a brute to drive, giving the power curve of most two strokes, which would make it even cooler!

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I think the anyone who want to have a flat plane V8 should consider reducing the displacement of the engine to 4 liters or less.

 

To my theory that might be wrong, all 4 cylinders engine that are <2.0L do no need the balance shaft to get rid of the vibrations. So as a flat plane V8 is basically 2 Inline 4 together, if the displacement for on each side is less than 2.0L (4.0L total for both banks together) it should not create thaose nasty vibrations.

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I think the anyone who want to have a flat plane V8 should consider reducing the displacement of the engine to 4 liters or less.

 

To my theory that might be wrong, all 4 cylinders engine that are <2.0L do no need the balance shaft to get rid of the vibrations. So as a flat plane V8 is basically 2 Inline 4 together, if the displacement for on each side is less than 2.0L (4.0L total for both banks together) it should not create thaose nasty vibrations.

 

Lets not do 1.00001 + 1.00001 = 2 engineering please...That doesn't work.

:wc:

 

The vibration is not directly related to the displacement, but rather the amount of stroke.

So the less stroke you have, the less vibration there will be.

There are other ways to lessen the vibrations with crankshaft design but it is always a trade-off with something else like performance.

For all practical purposes balance shafts are out of the question unless you have your own machine shop and can live with the extra weight.

 

Also the two banks of cylinders in a 90 degree V8 cancel out the vibration somewhat (I believe to the square root of 2) to about 140-150% of a standard 4 cylinder's vibration with half of the displacement.

40%-50% more vibration isn't bad to live with. With some nice fluid engine mounts that can be significantly reduced. Personally I'd want to solid mount the motor or use minimalistic thin rubber isolators if I were going to the trouble of making the engine actually perform rather than just sound cool.

 

OTM

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