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Is the Austin Healey 3000 a midengine design?

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Jedi Hopeful
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One never thinks of the Healey 3000 as a midengine design, but indeed it meets that definition. If you have changed the oil in your Big Healey, you are sure to notice how far back the drain plug is from the front of the car.

The engine is between the front axle and the driver, just as a Ferrari 308 engine is between the rear axles and the driver. In fact, it appears that more of the 308 engine is over the rear axle, than the Healey engine over the front axle. So our beloved 3000 arrangement is the classic definition of a midengine design (but it sure doesn't feel that way, does it?).

So now you have a trivia question for your next British car club dinner....

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Anyone can define a Healey or any other breed as a mid engine car if they joggle the figures around to suit their needs. Good grief, that would make just about half the cars out there as mid engined! No car with any part of the engine forward of the drivers feet is a mid engined car, doesn't even make sense to think so. Placement of the engine within the overall chassis is the determining factor, not actually where the driver sets! PJ
 
PAUL161 said:
Anyone can define a Healey or any other breed as a mid engine car if they joggle the figures around to suit their needs. Good grief, that would make just about half the cars out there as mid engined! No car with any part of the engine forward of the drivers feet is a mid engined car, doesn't even make sense to think so. Placement of the engine within the overall chassis is the determining factor, not actually where the driver sets! PJ
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It seems to me you contradict yourself in this post!
 
As the wiki article more or less says, we usually use "mid-engine" to refer to a car that has an engine in the rear, but in front of the rear axle line, siqualifying the old VW beetle, Porsche 911, and Corvair for example.

Technically a front engine car is "mid-engine" too if the motor sits behind the front axle wheel line, many many cars fall under this category, many miss it by a small margin because the engine is just a little too far forward.
 
glemon said:
As the wiki article more or less says, we usually use "mid-engine" to refer to a car that has an engine in the rear, but in front of the rear axle line, siqualifying the old VW beetle, Porsche 911, and Corvair for example.

Technically a front engine car is "mid-engine" too if the motor sits behind the front axle wheel line, many many cars fall under this category, many miss it by a small margin because the engine is just a little too far forward.
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Yes, that makes perfect sense to me.

Once I crawled under there, even when the Healey was on the lift, it was surprising to me how much engine there is, and how it is all behind the front axle line. And the transmission appears to be quite long in its own right.

The driveshaft must be a short little rascal.
 
:iagree:-----Keoke
 
We all grew up knowing that mid engine cars had the engine in the rear in front of the rear axle with the fire wall <span style="color: #CC0000">behind</span> the driver. A front engine car the fire wall is in <span style="color: #FF0000">front</span> of the driver. Elementary my dear Watson. Nuff said.
 
PAUL161 said:
We all grew up knowing that mid engine cars had the engine in the rear in front of the rear axle with the fire wall <span style="color: #CC0000">behind</span> the driver. A front engine car the fire wall is in <span style="color: #FF0000">front</span> of the driver. Elementary my dear Watson. Nuff said.
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I agree! "I think we grew up on the same planet".
 
If "mid-engined" is defined solely by whether or not the greatest portion of the engine's weight is located within the line of the axles then yes, the Healey is mid-engined. However this would not produce a very exclusive club, nor would many of its members have a reputation for good "handling" solely as a result of the engine's location.

The primary benefits a mid-engine location (whether front or rear mid-engine) offers are relatively better overall balance and lower polar moment which translate into what we commonly know as whether a car understeers or oversteers, with neutral handling being the elusive holy grail. These tendencies or characteristics are determined by many factors, engine location being only one of them. The old rule of thumb is that if the front end of the car goes through the fence first you have understeer-and visa versa.

I don't have my Healey road tests handy but I would estimate that AH's probably have 60-40 weight distribution, making the car very prone to understeer. OTOH a Porsche 356 would probably be the other way around and hence its reputation for being prone to oversteer. BTW the cast iron engine lump of a Healey 4 weighs less than that of a 6, thus giving somewhat better handling with lighter steering a byproduct.

The Elva Courier is a better example of what the term "front mid-engine" rally signifies. The weight distribution of a stock production car was approximately 53% front/47% rear, accomplished primarily by pushing the engine and transmission well aft into the cockpit. This distribution is gained by compromising somewhat on interior ergonomics and both the steering column and the driver's seating position run a couple of degrees out of parallel with vehicle centerline, though one gets used to this very quickly.
 
It is my understanding that in addition to millimeters this way or that of engine placement and perhaps equally important, the mid-engine issue is one of polar moment of inertia. That is when turning, what is the polar moment acting laterally across the axles, both front and rear. Any weight on top of the axle or in front/behind the axle, creates large polar moment thus trying to drag either the front or rear of car off the road.
However, an engine in between these two lines laterally across the axle puts that lump of weight in between these two vectors that work against getting the car to follow around the turn. An RX-7 Mazda (also Lotus/Caterham7) with the engine clearly behind the front axle was at the time of its introduction described as mid-engine. In the mid l950s many "front engine" F1 cars had the engine behind the front axle which was considered necessary for handling purposes.
About a year ago, an article in Road & Track comparing todays and back then F1 cars claimed mid-engine now but front-engine back then with picture of 1950s Ferrari that was clearly mid-engine. In response to my letter, their longtime technical Editor, Dennis Simanaitis wrote back that I was correct but today no one cares about such details so it really doesn't matter--not kidding that was what he said.
I am not an expert but have paid attention to reading about this for past 40+ years so feel that at least part of what I have written is really true and for sure back then was discussed in terms of relationship to axles not driver.
Jay Glass
'65 3000
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I don't have my Healey road tests handy but I would estimate that AH's probably have 60-40 weight distribution, making the car very prone to understeer. OTOH a Porsche 356 would probably be the other way around and hence its reputation for being prone to oversteer. BTW the cast iron engine lump of a Healey 4 weighs less than that of a 6, thus giving somewhat better handling with lighter steering a byproduct.
[/QUOTE]

According to the R&T road test that I have on file, for a (probably) BJ8, the F/R weight distribution with the driver in the car is 47%/53%.

Also note that almost every pre-WWII car was front mid-engine, only because the front axle was placed way out front ahead of the radiator. They weren't known for great handling, so as others have said, there's more to handling than engine placement.
 
I guess the most obvious example of axle way ahead of radiator is the Bugatti type 35, known for its remarkably good handling.
How many others had axles ahead of radiators? Sporting cars, but what else?
 
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