V8 Engine Note

[Stuart]

This may seem silly to some of you, but why do the V8's sound the way they do? It is unlike any other V8 I have heard.

Or are there any other engines out there that sound the way the Lotus lump does?

rgds

stu.

[Guest Chelsea Martyn]

I admit

The first time I heard a V8 start up, I was expecting a TVR'ish or typical V8 type sound also.

Saying that, My V8 has the Lotus sports exhaust as did all the ones I looked at before buying.

Maybe it has something to do with the 'shared' silencer box?

Maybe two independent pipes would resonate against each other better?

Saying that, they sound more like it when you are away from them a bit. Mine had some bushes replaced a while back, I was waiting for my lift and was about 200ft away. When the guy started it up to move it on the ramp it sounded more V8'ish then.

[Rob]

The 'burble' you get on US v8's is due to the crank design (usually cross plane) whereas the esprit v8 has a flat plane crank. Flat plane allows higher revs ie better for racing apparently.

A ferrari v8 also has a flat plane crank, but that gets its sound by clever merging of exhaust gasses - the esprit motor can't do this as it has twin turbos that effectively keep the exhaust gasses separate all the way out to the back of the car.

[hovgaard]

Most V8's use the cross plane crank, because it gives less engine vibration and a sound that people seem to like.

The flat plane crank results in a significantly better gas exchange process, allowing for a higher specific output.

[Stuart]

Ok, so now I am really showing my ignorance, what is the difference between the cross plane and flat plane crankes?

[hovgaard]

V8 engine crankshafts have 4 throws. On the cross plane crank they are phased 90 degrees apart, while on the flat plane crank the two middle throws are phased 180 degrees apart from the two outer throws like on a 4 cylinder.

[mchlrodrigues]

A ferrari v8 also has a flat plane crank, but that gets its sound by clever merging of exhaust gasses - the esprit motor can't do this as it has twin turbos that effectively keep the exhaust gasses separate all the way out to the back of the car.

<{POST_SNAPBACK}>

I had always wondered why Ferrari V8s sound "better" than the Lotus motor (to my ears). I had always attributed it to their short stroke and oversquare dimensions, but this was just a guess.

An F40 has a flat crank twin turbo V8 as well. How is it that they sound substantially more interesting, or at least different, than the Lotus lump? Could it be in the headers that direct the exhaust into the turbos, or the firing order perhaps? They run both cylinder banks into a single muffler at the back similar to an Esprit.

Anyone know or care to speculate?

[Rob C]

This may seem silly to some of you, but why do the V8's sound the way they do? It is unlike any other V8 I have heard.

Or are there any other engines out there that sound the way the Lotus lump does?

rgds

stu.

<{POST_SNAPBACK}>

Hello Stuart..here is my few words...back in 1989 I built my first V8 Powered Lotus which was of course a Rover Lump 3.5ltr in a Lotus 1974 Elite...then less than 18 months later..not powerful at 200bhp I went for a John Eales 4ltr screamer..near 300bh with 4x4 Dellortoe's in 1990...now that made the right noise...proper yank type V8 low throb base at low revs and a high scream over 5.5k up to nearly 7k...

My Sport 350 with Cats and Pipes sounds nice...the best sounding Flat Plane V8 has to be Mike S's GT1 monster clone..ForSale... with full on Inter-coolers and the pipes longer and curving in an S patern coming out in the middle of the car.

By the way our cars run like Two 4 Cyl Engines side by side....

I have a nice V8 Elite Video should any member want to see some thing I think its rather good..Mid 90's...my car at Castle Combe...On IT Big Time...Rob