Front Engine vs Mid-Engine

Hey Gordon

I watched "Victory by Design" episode about Ferraris on Speedvision this week.
I'd seen it before, but it's pretty neat
so I watched it again.

Alan DeCadenet drives all kinds of rare
Ferrari street and race cars, and at the end of the program declares he'd rather drive a
front engine car on the street.

I know that's just one man's opinion, but my question is what's different in the handling
between front vs mid-engine that might cause
him to make that statement?

Thx

MikeD

I suspect his preference may be based not so much on performance as on safety and comfort. Let's take these one at a time:

Performance - A mid engine car has a lower polar moment of inertia, which is certainly preferable on the track (quicker turn-in, etc.) and shouldn't present a problem on the street. The only problem I foresee would be a mid-engine car's tendancy to spin when pushed beyond its limits, as in trailing-throttle oversteer, as opposed to the more benign understeer that most front-engine cars tend towards.

Safety - In a high-speed impact, you have the engine infront of you to help absorb the impact in a front-engine car, while in a mid-engine car the engine will be trying to squish you between itself and whatever you ran into.

Comfort - Mid-engine cars tend to be noisy, what with the engine a few inches behind your head. Mid engine placement also tends to limit cockpit space.

The reality is, of coarse, that it makes very little difference from a handling perspective unless you're driving either of them at their limits.

Under these conditions, a good mid-engined car requires a specialised technique if you were to get the highest corner speed out of it.

This techniquie requires you to drive it hard into a corner to the point of slight understeer, and then power it through to promote a little oversteer (to counter the understeer).

If you were to drive it a little slower through the corner, then you would promote too much oversteer (resulting in a slower speed). Drive it a little faster and you'll spear off the track (resulting in slower speed again ).

Now I said "track" deliberately (girls and boys, don't try this at home ) because on a track you come across the same corner over and over so you get to find that perfect speed. But to find that perfect speed on a public road is far more difficult, unless it's your favorite section of road and you have done it many times before.

Most people will, rightly, tend to drive their mid-engined cars at speeds below the "slower oversteer" speed, though assuming that it can't go any faster. They might even describe a well set up track car as being a little "taily". At these slower speeds however, the car will behave much like a front engined car, but will probably be a little slower than its front engined counterpart.

In forms of racing where front or rear is allowed (per class), what are the successful teams/cars that are front engined?

I prefer the look and feel of the mid-engine design, but I never thought about the consideration of a front end collision. Having 500+ lbs bolted securely infront of ones body to absorb shock and be a barrier does make me think.

Ibelieve that it was Bob Bougerant (spelling up to my usual high standards I supose) that said that the average driver can get a front engined car to perform better but an experienced driver can get the MID engined car to perform better.

This will be as has been said earlier on this thread that the mid engined car needs to be driven.

Both cars are well mannered under mundane driving but the rear engined car's rear breaks loose very quickly if the driver changes his / her mind mid-corner. They are said to be less forgiving. The breaking away can almost be a 'snap' if the weight distribution is close to the 50/50.

Our cars have a mid corner understeer and for this reason I like to control the car under throttle from entry.

To sumerise , a mid engined car makes you feel alive !!!

Best wishes,

Robert

To CCX33911,

Your question has really got me thinking. This is what I've come up with, but I'd like to try to answer your question more broadly.

Its probably safe to say that the mid-engined cars have it on all circuit type events - eg. Touring cars, Formula 1, Indy etc.

Whereas the front-engined cars tend to have it on open road events - eg. World Rally, Targa, Cannonball etc.

Don't forget the rear-engined Porsches here which seem to always be the exception to the rule. Its amazing what they've managed to do with a configuration which, by all rights, SHOULD be a real dog by todays standards.

Its probably also worth pointing out that front-running rally cars all tend to be front-engined, All-Wheel-Drive configuration these days.

Good point on the World Rally, etc. I wonder about Pikes Peak. I would guess (having not paid attention to the finishers, etc.) that front engine would do well there also.

Gary

Gary,

As famous as Pike's Peak is, we don't get alot of information here in Aus about it, but am I correct in saying that there seems to be quite a few more mid-engined cars that compete here than you would expect for a road event?

Maybe thas 'cos it could be seen as a "single lap" event, since most front-runner competitors would probably know every corner like the back of their hand.

I think it is something like 130 turns though. Wow!

if you really want to prove this point, try either gran turismo 2 or 3 on the playstation. gt2 has a better array of cars, so id reccomend it. you get a real sense drive characteristics. gt3's strength is the track displays are better.

[ April 08, 2002: Message edited by: GT40 MKII ]

Just my 0.02$ on everything.

The engine is a rather hard, wont's squish when you run into a pole if you know what I mean, that's why the engine mounts are weak points: to drop it down.

All Pikes Peak cars in the Unlimited class I know of are mid engined. The group B rally cars were mostly mid engined (Stratos, Renault 5 Turbo, Ferrari 308 - I'm not sure if that one got to race before they cancelled the class, 959 ofcourse but that would be rear) with the big exception being the Audi. I think the biggest performance advantage is in the braking as there's less weight shift; grip remains rather even. It makes sense since most cars tend to decelerate faster than accelerate. group A and present WRC class cars were and are subject to homologation constraints. For group A you needed to build 2500 cars, group B - 200. WRC class requires a mass produced car with allowed mods being turbo and 4X4 (but the suspension geometry must remain with end point discrepancies of no more than 20mm). Group B cars were monsters pumping in excess of 600 horses, but the current WRC class cars would outrun them on all but the fastest sections due to the advances in suspenion engineering.

The bottom line is this: in a controlled level playing field you will be stripped out of any horsepower advantage, and even if you manage to get away with it, the guy who can break later and harder won't trade that for horses.