Flat Plane Cranks

This issue has been bugging me for years.

Did one of the guys racing Mustangs back in '66-67, re engine his car with a flat plane crank motor? I can't recall the exact meeting, but one of the Mustangs - white with stripes, I'm sure , had an engine that sounded decidedly different - more like a straight eight (think Bugatti-ish). It wasn't Fahey - could have been Coppins. The announcer said he was running a flat plane crank in his engine!
At the time, I thought "Oh yeah, that's interesting", but thought little more about it. When Yamaha put a flat plane crank in the R1, it re-awakened the niggle.

Anyone?

I'm sure Coppins was running an engine with a flat-plane crank at the Easter '68 Bay Park meeting where the lightweight Aussie minis guested. Sounded fabulous, and the howl exited through a big collector exhausting just in front of the left rear wheel. Also had Gurney Weslake heads fitted for that meeting as I hotfooted it to the pits to get a look under the bonnet at what the hell was making that wicked tone. Lucky me, I was flag marshalling for that meeting at the entry to the right hander, so also had full benefit of the cars (and bikes) on full song half way down the back straight. Later I recognised that the sound of the GT40 was the same, confirming my suspicions...:cool:

Yes I'm sure GT40s had these cranks. They make a completely different sound once the revs come up. I thought they sounded almost like a big 4 cylinder.

I could be wrong but my understanding was that distinctive sound from GT40s was due to the cross over (nest of snakes) exhaust system. This was probably what the Mustang had. I think the first experience with flat plane cranks in NZ in a V8 (apart from the Cosworth DFV) was with the Repco Holden F5000 engines. However I am willing to be proven otherwise.

wheres Jac Mac when ya need him he,s bound to know

The exhaust on the GT40s had the two centre cylinder exhaust pipes of one bank coupled to the the two outer cylinder exhaust pipes of the other bank just behind the engine in order to give better scavenging. This is probably what made them sound different. With a flat plane crank you could run a seperate exhaust system down each side of the engine. With a flat plane crank you virtually have two inlne four cylinder engines side by side.

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Originally Posted by SPman

This issue has been bugging me for years.

Did one of the guys racing Mustangs back in '66-67, re engine his car with a flat plane crank motor? I can't recall the exact meeting, but one of the Mustangs - white with stripes, I'm sure , had an engine that sounded decidedly different - more like a straight eight (think Bugatti-ish). It wasn't Fahey - could have been Coppins. The announcer said he was running a flat plane crank in his engine!
At the time, I thought "Oh yeah, that's interesting", but thought little more about it. When Yamaha put a flat plane crank in the R1, it re-awakened the niggle.

Anyone?

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I remember a F5000 at Wigram over 30 yrs ago that had a flat plane crank...I was a different sound and it was new to me so I asked and was told why. For 10 points who was it? (Hint an Aussie). Chris Read, Arrowtown.

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Originally Posted by Chris Read

I remember a F5000 at Wigram over 30 yrs ago that had a flat plane crank...I was a different sound and it was new to me so I asked and was told why. For 10 points who was it? (Hint an Aussie). Chris Read, Arrowtown.

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John McCormack Elfin MR6

I think he had one in his Charger also

Anyone remember the little Nissan Sunny's that Terry Gladstone used to race in Sport Sedan series? Powered by Rover V8's - pretty sure they had flat plane cranks in them.

That sounds feasible as a flat crank Olds was an option .

Trevor Crowe had a flat plane crank in at least one of his many Olds V8 engines that he used his Starlet V8s.

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Originally Posted by Carlo

John McCormack Elfin MR6

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Was that the Repco Holden or Repco Leyland V8? Both engines could be had in flat plane crank versions.

"Was that the Repco Holden or Repco Leyland V8? Both engines could be had in flat plane crank versions."

Wasnt the Leyland engine in the McLaren F5000 car that he built?

The MR6 was built for the Leyland engine. Later it was installed in a McLaren M23 (ex F1).
Dale.

friend of mine bought the red dawson mustang around 1970 I think. That had a true 180 degree header system fitted which was a PIA to remove, but it did sound nice. from memery the SBF would rip the centre mains out if run with a flat plane crank as did the rover V8s