Combining two inline 4s to build a V8 ?

[countersteer]

Makes me think of the MotoCzysz C1 motorcycle engine. Clean sheet inline 4, mounted longitudinally, but had twin counter-rotating crankshafts to eliminate the gyroscopic effects. Triple camshafts with the intakes located between the centrally mounted intake cam and the outboard exhaust cams providing for a straight shot to the intake valve.
http://www.motoczysz.com/rss_news_view.php?id=66

[Edis]

Like taking a real inline, make a new crankcase and crankshart, edit the timing and voila, a V8 on the cheap.

How on earth is making a new crankcase and crankshaft considered on-the-cheap?? The crankshaft is probably one of the most expensive parts on the engine.

Not to mention, if you go down this road the only thingd you can use from the whole 4 cyl engine is the head, pistons and conrods. Everything else needs to be binned and redesigned from scratch.

Not that is a bad thing. Then you get porn like this.
...

I did not know it was the most expensive.

It will save you the R&D money though...

Those Hayabusa V8 are awesome 450hp from 2.8 liters and a weight of less than 100kgs.. Me wantee [-o<

Cheap or expensive depends what you compare it with. Compared to buying a complete production engine making your own engine is obviously very expensive. But compared to making your own engine from scratch, it is a lot less expensive. After all, a significant part of the engineering work have been done for you, and you can carry over some of the more expensive parts such as the cylinder head casting. If you think getting a crank made for you is expensive that is nothing compared to the cost of the tools required to produce cylinder heads. At least the crank and crankcase can be made as "machined from solid" components which is significantly cheaper if you only plan to build one or a few engines.

Still, if you haven't a CNC mill you can use, expect to pay for at least a few hundred hours of work making the components you need. That is, assuming you have been able to design the parts yourself.

[donskar]

HI

This is going around my head for a bit, and I cant really find an answer for it.

Is it possible to combine two 4 cylinder inline engines to create V8 ?
Like taking a real inline, make a new crankcase and crankshart, edit the timing and voila, a V8 on the cheap.

I know the Porsche 944 engine is half the 928 V8, but is it possible the other way around ?
Like gluing two Alfa twin sparks together ? (they sound good)

Or a boxer 8 to simplify timing... ?

Triumph Stag V8?

[greencow]

Joining two I4s was how Cosworth made their Double Four Valve engine, turned out quite well IIRC.

[Sayshina]

Wankel Rotary doesnt actualy have one.

Yes, you can plumb together a bunch of wankle units and make a near totally impractical engine.

But as far as making an actual V-8 out of 2 inline 4's, it's been a bunch of times and all of the professional ones wind up costing between $20,000 and $40,000. At those prices, I'd say the estimate of $100,000 initial outlay might actually be a bit conservative.

It's massively expensive. If you're going to do it with a single crank. If you're going to gear 2 separate 4's together that can often be done fairly cheaply. No guarantees though, and it usually winds up making an engine that's bigger, heavier, and makes less power than a decently tuned production engine of the same displacement.

It's just not worth doing, unless you plan on producing and selling them, in which case there are already several established units you'd have to compete with. If you want a really light high output V-8 just buy a Cosworth or Judd. If you can't afford one you certainly can't afford to try making your own.

[hecti]

i give you the hartley v8:
http://www.h1v8.com/page/page/1562068.htm
its the one used in the atom v8 (pictured in page 1 of this thread)

[PhillipM]

I see your bike engine derived V8 and raise you a bike engine derived W12, built by a bloke in a shed for an amateur race series

[OnterW]

Didn't VW take their VR6 and combine two to make a W12? I was thinking they did something similar to make a W8 too. I guess in the end, anything is possible after looking at those tractors.

[Belatti]

I have heard that from 2012 the Argentinian TC2000 Championship will have bike derived V8s manufactured in England.

The news that reached to me is that is the Radical V8, arround 400HP.

The problem here is that TC2000 (something similar to WTCC) has historically been a FWD series... will we see madness? (that is, 400HP + FWD)

[marcush.]

I have heard that from 2012 the Argentinian TC2000 Championship will have bike derived V8s manufactured in England.

The news that reached to me is that is the Radical V8, arround 400HP.

The problem here is that TC2000 (something similar to WTCC) has historically been a FWD series... will we see madness? (that is, 400HP + FWD)

the Radical V8 is a bit longer than the Hartley as it has a shallower V-Angle as you run out of space with the bolts in the valley ...