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


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There aren't many 4 cylinder engines with 112mm bore spacing. VW/Porsche cranks use 112mm bore spacing but they are a flat 4, not I4. (VW aircooled type 1)

 

That makes me think of a DOHC VTC air/water cooled VW type 1 using some cut up VH45 heads but I digress...

 

 

Next you’ll find his parents Briggs & Stratton lawn mower with one cylinder of a butchered VH45DE cylinder head, one primary tube of a rusty L-28 header on it and the smog pump off of a ‘70’s Chevy pickup as a Super Charger!.. :lmao:

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Well this is Way out from left field but here goes. Now keep in mind this part be more rare than our OS Giken heads but I havn't looked into sourcing one yet. Here is the scoop. In 1930 Pontiac had a deal going with a company called Oakland. In that partnership they built from 1930-1932 flatplane cranks for their cars. I don't have production figures but estimates put it in the low thosands.

 

Quote explaining the motor.

 

"It is a fascinating engine. It is essentially a side valve engine but the valve stems all lie in a horizontal plane across the top of the engine. The valves are rocker operated and there are roller cam followers. It is 1/16" oversquare. The head gaskets start at the top of the engine vertically over the valve heads then bend 45° across the piston tops. It was intended to be a cheap engine so it has a flat plane crank. Flat plane crank V8s vibrate so Oakland came up with a very ingenious way of isolating the vibration from the car by mounting the engine on leaf springs and then preventing the mounting springs from becoming excited at critical frequencies with a clever mechanism called the "synchronizer". They do not exhibit any vibration when driven."

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A bit more info explaing the exhaust. I know it confused me.

 

Exhaust from the right bank is directed to the left side of the engine, preheating the manifold centre section under the carburetor as it goes. The main exhaust outlet is a cast passage from the top of the block through the water jacket between the centre two cylinders on the left bank to the outside where the exhaust pipe is connected. It is the relatively large hole visible on the top of the far side of the block in the photo of the engine in pieces. I suspect this contributes to a reasonably quick coolant warm up from cold start but the cooling system works very well with no sign of overheating. I have driven the roadster in peak hour traffic for half an hour without the fan on a 100°F day. I switched off at red lights and restarted on green. Admittedly it does have a new modern core. My sedan with original core in unknown condition does not work as well.

 

The engine does not have an oil filter. The sheet metal in the sump is there for carrying fine gauze over most of the area through which the oil drains and is "filtered"! The centre of the sheet metal is folded down to form two surge baffles. Although the oil pump is at the back of the engine, the pick up is in the middle of the sump between the baffles.

 

 

TECH DATA

 

Valves are 6 1/2" long overall. Stems are 11/32". Guides are 3 11/16" long and 11/16" dia. Protrusion into port is 5/8" dia by 1/2" long.

 

Crankpins are 2 1/4" dia. Rod big ends are 1 5/16" wide and rod centre distance is 6 5/8". Piston comp height is 2 1/4".

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For those new to this thread and concept of single plane V-8 crankshafts, (there was some confusion as to what they are), Here is some more info;

 

 

501233330300jpg_00000046717.jpg

 

With the 90° crank (above' date=' far left & mid left)[/i'], two of the cylinders on each bank fire in succession. With a 180° crank, (above far right & mid right), the cylinders fire alternately from bank to bank. Evenly spaced exhaust pulses and higher speed produces a high-pitched Indy-car shriek.

 

501233330302jpg_00000046718.jpg

The IRL Aurora V8's conventional 90° crankshaft has four connecting rod pins at 90° intervals, (above left). The 3.5-liter crankshaft has its rod pins at 180° intervals, (above right). This 180° design is called a flat crankshaft because the pins are in a single plane, Single plane crank, 180 Degree crank, flat plane crank.

 

Here is another cool link…

http://images.google.com/imgres?imgurl=http://www.cowdery.org.uk/images/engines/Flatplane.gif&imgrefurl=http://www.cowdery.org.uk/cranks.php&h=301&w=351&sz=319&hl=en&start=22&sig2=a8Uz6ESTEWcMiLiCXYZS6g&um=1&tbnid=2pwGPwAKkZ5MNM:&tbnh=103&tbnw=120&ei=3U7ER7C6NqD4gAOQ5JDUCA&prev=/images%3Fq%3D180%2Bdegree%2BV8%2BCrankshaft%26start%3D18%26ndsp%3D18%26um%3D1%26hl%3Den%26client%3Dsafari%26rls%3Den%26sa%3DN

 

 

Dual Plane V-8

Dualplane.gif

 

Single plane V-8

Flatplane.gif

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Wow, most informative thread Ive seen on any forum in months.

 

Yall have explained so many things Ive been curious about but never knew how to ask. I must say that Vette with 180 degree headers still sounds like an average Vette to me. Even the GT40 didnt sound Ferrari-like IMO.

 

Question: Is there a reason these Ferrari V8s seems to rev (and return to idle) so quickly? I'm guessing its because the recipricating assembly is lighter than the bigger domestic V8s so theres less intertia to overcome.

 

Thanks again for the schooling!

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Question: Is there a reason these Ferrari V8s seems to rev (and return to idle) so quickly? I'm guessing its because the recipricating assembly is lighter than the bigger domestic V8s so theres less intertia to overcome.

 

 

Exactly.

Very little rotating mass when compared to a 90 degree crankshaft. My 90 degree VH45 crankshaft weighs about 52 pounds. I would expect a flat plane crank for the same engine to weigh about 2/3 the weight because of the reduced need for counter-weights.

 

OTM

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That Lambo has a V-12 engine, though that particular Lambo's exhaust note is not typical of V-12 exhaust notes, which is generally quite similar to the inline 6, just smoother and more refined sounding in my opinion, (due to its evenly spaced firings and paired/joined primaries). Inline 6 and V-12’s have a smooth voice with a bit of an accent. More of a brrrraaaap vs baaaaaap, a growling GRRRR in the tone.. (that’s the best way I could describe it any how). That particular V-12 though didn’t have much of that GRRR in it’s note like a typical V-12. It sounded more like a single plane V-8, either way, it sounds incredible…

 

Here is an example of how the typical V-12 normally sounds, you can make out the V-12 growl in the tone...

 

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This is the most WICKED sound I've EVER hear! BMW inline sixes FTW!!!

 

 

That's a E46 M3 CSL with a supercharger, some internal mods and a freeflow exhaust...

 

Prox, looks like you won't have to buy a V8 to have such sound. :)

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4 cylinder cranks, Eh? I had someone measure a Porsche 3.0L S2 I4, they came up with ~4.8" bore spacing.... With a 4 cylinder crank though, aren't the journals for the connecting rods only really meant to fit one. I would be afraid that there wouldn't be any room to machine in another...

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Guest speeddemon76

WHY high revving?!

 

for some disgusting reason I am obsessed with Formula One and super cars such as the Pagani Zonda and the Ferrar F430 and FXX... the sound.. ohh the sound!

 

you just want ppl to think to them selves WTF? when you blow by them would be insane and extremely bad ass though

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