Straight Horizontal Engine

[Vladmir123]

Hello,


I've been trying to design a one seater racer around a straight inline 4 cylinder engine. But I'm facing a weird problem. There is no space to keep the engine in it's vertical position and the only way it'll fit is if it's placed horizontally. I wanted to know if that's okay to do .. I see a few problems with the cooling as lubrication system if that's done. But I'm not sure. Anyone know anything about this ?

Thank you in advance

[Greg Locock]

Oil will be your biggest problem, you'll have to arrange returns from the bottom of each cavity. Apart from that it should be OK, but I have never done this so there may be more traps.

[strad]

I think it may have been Smokey turned one on it's side for Indy..With a dry sump everything else can be overcome.

[xpensive]

I seem to recall that one of the problems with the 18 degree BMW 14 turbo of 1986 was oil surge in the right hand corners?

[autogyro]

It should not be rocket science to design an oil return and dry sump system without surge problems.
My friends DH Tiger Moth has an inline four that is upside down and that has no problems even in loops and rolls.

[mcjamweasel]

BMW have done it in their K1200 bikes, have a look at them.

[langwadt]

Hello,


I've been trying to design a one seater racer around a straight inline 4 cylinder engine. But I'm facing a weird problem. There is no space to keep the engine in it's vertical position and the only way it'll fit is if it's placed horizontally. I wanted to know if that's okay to do .. I see a few problems with the cooling as lubrication system if that's done. But I'm not sure. Anyone know anything about this ?

Thank you in advance

must be possible, else how could flat or boxer engines work?

[andylaurence]

I'm intrigued how an inline-4 can be better horizontally than vertically in a single seater. Vertically usually makes for a better shape for the coke-bottle and the floor can be raised either side if that's allowed in the series. Then there's the drive to the gearbox from the crankshaft, which means that lying it horizontally will put the crankshaft off-centre if longitudinally mounted and sourcing a gearbox will become an interesting conundrum unless you're happy with an offset differential. You could mount the engine transversely to avoid those problems, but that might prove interesting with the wheelbase.

As far as practicalitites go, it's oil scavenging that'll be the biggest issue, but many cars pull >1G in the corners and cope just fine with just a dry sump, so provided you can site the scavenge for the dry sump appropriately, you might find it works out OK...

[marcush.]

I´d think one of the issues you face is how to avoid oil getting into the inlet and possibly exhaust ducts through the valve guides .But in essence you need to look at the oil supply and scavenging with the flat orientation in mind .The Bimmer mmotorcyle but more interestingly maybe the flat fours/six óf Honda Motorcycles (yes the Big touring bikes )maybe a good source ,espoecially when Honda usually does publish a lot of technical detail...

Offenhauser 4 bangers were used in lay down position early on (Kurtis )and extensively in the 1970s ...

http://indyroadsters.webs.com/apps/blog ... comparison

[dren]

I seem to recall that one of the problems with the 18 degree BMW 14 turbo of 1986 was oil surge in the right hand corners?

The Honda Prelude had an 18 degree I4 that slanted back towards the firewall, although it was transverse mounted. They didn't have any oiling issues that I can remember. Weren't the BMW I6s also at an 18 degree slant?

[xpensive]

Just to be clear, The 1986 BMW F1 unit was 18 degrees to the horizontal line, slanted 72 degrees in other words.

[MOWOG]

BMW has been building horizontal 3 and 4 cylinder motorcycle engines for 20+ year now. I imagine there must be lots of info on how they handle the oiling of those engines. Also, any flat 4 or flat 6 engine from Subaru or Porsche has to face most of the same issues.

[dren]

Just to be clear, The 1986 BMW F1 unit was 18 degrees to the horizontal line, slanted 72 degrees in other words.

Ha! Thanks.

And for the boxer engines, the only issues I've heard of from the Subarus are the head gaskets, but I'm assuming it might be more from the boosting than from the layout.

[Tommy Cookers]

the motorcycle examples are surely worthless (because they lean to corner so 'g' is not a factor)
eg you would have oil scavenge/churning problems with such an engine used in a race car (otherwise a good idea ?)

Indy cars with 'laydown' engines were surely designed to naturally scavenge when turning left ??
most 'road' circuits have more left bends than right, you should design the car around this
(in the UK tracks have more right bends)
you don't want to be allowing in your design problems that need F1-style features to treat them
whether in oil or cooling systems

an underappreciated advantage of our roadcar transverse engines is reduced oil churning (compared with longitudal arrangements) both in cornering and acceleration
even today there is no public specification for anti-foaming properties of engine oil ?? (important to hydraulic tappets/lifters)
'slant 4s' were once quite common, their oil systems were not suited to tracks with many right bends
today's short slow bends and chicanes are easier of course

[MOWOG]

[...] I realize that in Europe, motorcycle riders never drive straight and level, but here in the US, it is not unusual for riders on the SuperSlab to travel in a straight line for hours on end. [...]