You can't really compare a turbo to an NA there!!!

6-Bolt mains and linerless bores - love it!!!

This thing would absolutely haul ass in a mini....

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"Not Speeding Officer..........Qualifying"

There's a world of difference between a V4 and a harley. Harleys vibrate because the angle between the cylinders is 45 degrees. Ducatis (also V twins) don't vibrate because the angle is 90 degrees. Japanese engineers couldn't bring themselves to build an engine as inherently bad as a HD motor, so the crankpins in my M50 (800cc v twin) are offset; it has a solid mounted motor and barely vibrates at all. My VFR750 (v four engine) was smooth as silk.

Lancia knew a thing or two about V4's too.. and their were good motors.

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Simon

The adventures of an owner builder in the Tallarook Ranges

Honda found out the best angle in terms of comactness and anti-vibration is actually 52 degrees. I think all Honda V's, no matter whether they are V-Twin or V4, are 52 degress?

Cheers,
Tricky

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"Not Speeding Officer..........Qualifying"

hmm thats a good alternative to a bike engine for a rwd sports sedan mini!

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Potato

Tricky,
According to the great Australian engineer Phil Irving, who designed the Repco V8 (also wrote Tuning for Speed, and other books) a 90° V twin can have perfect primary balance. You just counterweight all the reciprocation component of 1 piston and rod, and none of the other. Then the forces balance each other out. Of course, the firing intervals are way uneven, but a Ducati in full song does sound great, hey!
Most V2s of lesser angles had it to save space, or for some other reason than balance.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Hey Doc,

Yep, you are 100% correct. A 90 degree twin (or mutliple thereof) is the easiest in terms of engineering out harmonic vibration and ensuring perfect primary balance.

Honda only went to the 52 degree V-Twin becuase it was a lot more compact - and it was only for that reason. I think they treied 75 degress, 60 degrees etc and then finally settled on 52 degrees.

And yes, nothing like a 90 degree Ducati at full song - love the desmodromic valve operation purring at 9000rpm!!! You Doc, have excellent taste Sir!

Cheers,
Tricky

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"Not Speeding Officer..........Qualifying"

So what was the angle of the HRD Vincent V twin that Phil Irving designed? (a lot less than 90°)
The problem with a lot of motors is not primary balance, it is secondary balance. The V4 chev speedway motor has bad secondary balance.
Comfort is not usually a high priority in speedway.

OT but I was just reading one of Phil Irving's books the other week. What a legend - I'll dig up some quotes. He "accidentally" designed his V twin when two sketches of his inline engine fell on top of one another, overlapping to form the V shape!

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How hard would it be to cut a V6 or V8 down yourself?
A 3.8L V6 commy will give you a 2533cc V4.....just a spur of the moment idea
But seriously how hard is it to cut a engine down and what would you need to look for?

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Respect mine and I'll respect yours.

why cut one down when you can buy a proper speedway one for 7 or 8 grand

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Potato

We used to have a V4 Ford Corsair 2000e. Not all V4's are a good thing.



Same motor was used in the Capri 2000GT, and of course in a lesser form in the early Transit Vans.

Cheers,

Dicko

Haha, we used to have a V4 transit van. That thing was hilarious. Used to hate going in it as a kid cause it was ex-spastic society pale blue and you could still make out where dad had pulled the signs off. Later on when I drove it I used to love it, high up truck driving position, revving the crap out of the V4 and going nowhere. Fun stuff. Think we sold it for $50 to the kids from round the corner.

There have been some very good V4s in this world, and also some very bad ones. That Ford V4 was the latter.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.