The Porsche transaxle was inverted in Lionels "Evo", supposedly because the Alfa engine ran opposite direction to the Porsche engine.
Have I got that completely wrong?
And that did require an oil pump, cooler and breather system.
The Porsche transaxle was inverted in Lionels "Evo", supposedly because the Alfa engine ran opposite direction to the Porsche engine.
Have I got that completely wrong?
And that did require an oil pump, cooler and breather system.
No John,
A rear engine transaxle (911/Beetle) needs to be inverted for a mid engine car (like a Hewland that has the drain plug facing upwards, because it started life as Beetle gearbox).
That's easier for me to understand than this Pantera/GT40 thing.
All the engines turn the same way.
Last edited by ProtoTipo; 13-05-2019 at 15:19.
B series Honda engines turn counter clockwise, but they are the only modern engines I know of with that configuration - there are probably various pre-war oddities as well.
Perhaps it all goes back to the Starting Handle and the majority of people being right handed. Perhaps the Honda engine was designed by a left handed person, or am I being discriminatory?
Last edited by Longtimefan; 13-05-2019 at 18:44.
As Chris says the Porsche 911 is rear engined with a forward mounted gearbox (transaxle). In the Porsche the input shaft is quite high because of the flat 6 engine requiring space underneath it for the exhaust manifolds etc.
If you were to spin the box round to suit the mid engined rear facing gearbox without inverting it then you end up with 1 forward and 6 reverse gears.
In a mid engined low ground clearance tarmac/road/sports cars such as the Gt40, Ultima, T70 etc where I have seen the Porsche box used then it is advantageous to have the box inverted so that the pinion shaft (and subsequently diff and output flanges) is 75mm above the input shaft/crank height as this gives a much better angle on the driveshafts. In the Napiersport EVO then it did not need an oil system but it was probably deemed advantageous to fit one. A breather system was required for sure. The later Getrag Porsche Gt2 & Gt3 boxes did have an internal oil system (& an external heat exchanger) and this did need to be modified to function once the box was inverted
On the 037 which was a rally car and therefore probably ran more ground clearance then it would be better to have the output flanges below the input shaft to get a better range of travel for the driveshafts.
"You can lead a horse to water, but a pencil must be lead"
Stan Laurel
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