Talk:Mid-engine design

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This article should be merged with MR layout Grs1969

Doesn't make sense, since mid-engine can be MR or MF. The features common to both should be elaborated in Mid-engine design.66.77.124.61 16:51, 15 May 2006 (UTC)

Ditto the it doesn't make sense. The bit about polar moment of inertia isn't right. AFAIK, the mid-engine design is done 'cause of acceleration and stability-- which is related to center of mass and wheel base (spacing of the wheels, distance between the wheels). Straight line stability -- last time I checked -- Newton's first law said things go in a straight line... unless there is another force acting on it. I assume what was meant was... the issue related to breaking and weight shift. With breaking-- weight shifts to the front and one may get an nasty oversteer (as seen in the first Audi TTs), that in an unexperience driver leads to an accident. Anyhoo... first good attempt--article needs some work. Nephron  T|C 07:27, 11 August 2006 (UTC)
The only straight line stability issue I can think of is that mid-engine cars sometimes have their center of gravity aft of their lateral center of pressure, which can cause issues in heavy crosswinds. I'm not sure if that's what the original author meant, or if it's even worth mentioning in the article, though. DoktorRocket 00:13, 19 August 2006 (UTC)
I've a hunch it has to do with fuel packaging, too, leading to Cg movement as it burns off. This seems to be what the article implies, & it tallies with what Len Terry's book suggested. (I'm not an engineer, but that was the sense I got.) Trekphiler 09:09, 6 November 2006 (UTC)

If MR and MF were to be changed into subsections for Mid-engine, that would justify the merge. Otherwise the article MR is a distinctively different article from mid-engine as stated above. The polar moment of intertia is different between every MR configuration vehicle. Article needs editing but should stay.

Contents

[edit] Proposed merge

  • Support there should be a merge... only question, IMHO, is which way. I spent some time in the automotive industry and I'm not familiar with "MR" ... so I think merge should go into "Mid-engine design" -- which I think is in accordance with the Wikipedia naming guidelines (WP:Naming) --the name should be simple and recognized by most people. Nephron  T|C 07:41, 11 August 2006 (UTC)
  • Support And agree that it should go to 'Mid engine design' - more recognisable for most. Watch out for other articles in the set, I assume there are FR and FF articles around as well. In reply to the objections above, neither article is currently very long so all variants on mid engine can be covered. (Incidentally, my understanding is that MR means Mid engine Rear drive. The 'front mid' layout that BMW claim (engine in front of driver, but between axle lines, driving rear wheels) would not be MF as referred to above, but still MR.) 4u1e 03:04, 20 August 2006 (UTC)
  • Refute I disagree. The purpose of defining "Mid Engine Layout", and "Mid-Rear" as seperate definitions, is because they are two different concepts. Saying that an engine is Mid-Engine, does not mean that it is Mid Rear. It could be Mid-front.
  • Support, even manufacturers of cars with engines mounted in front of the driver and behind the front wheels, such as many of the GT Ferraris, do not describe such vehicles as mid engined, but front engined. In fact, very few front engined vehicles have their engines truly mounted ahead of the front wheels. Mid engined pertains to an engine mounted behind the driver. Rear engined refers to an engine mounted behind the rear axle. These are the common and established permutations and nomenclatures.Michael Calwell 21:56, 29 October 2006 (UTC)
  • Refute Placing the heaviest component of an automobile in the middle of the car produces a distictive set of car handling characteristics regardless of the driven wheels. The purpose of a seperate article in Wikipedia is to describe distinct things seperately. The placement of the engine in the chassis (front, mid, rear) and the drive wheels (front, rear all) are not directly connected. Using auto company marketing materials is a poor guide to the correct encyclopedic definition. RMR is the most common type, because of the documented problems of packaging a vehicle with the engine inside the wheelbase, but trying to shoehorn all cars with the engine located completely inside the wheelbase into RMR is unworkable. PLawrence99cx 04:56, 3 November 2006 (UTC)

[edit] Mid Engine 4 wheel drive?

Are there any vehicles with this feature? Doesn't seem technically impossible. What about the Toyota Previa?

The only one I have personal experience of is the Volvo C303. The engine sits below the wall separating the driver's area from the cargo (or passenger) space. Two lids give you access to the engine from the inside of the car. http://www.real4x4.com/Volvo303.shtml gives some pictures that show the engine placement. // Liftarn

[edit] Mid Engine?

Engine in front of the driver is mid-engine? Since when? Trekphiler 08:53, 6 November 2006 (UTC)

The Front-Mid designation is a questionable one. When looking at the layout of a powertrain there is a big difference between classical rear engine, mid engine and front engine layouts. These terms general date back to when engines were longitudinal in most cars. As such it the location of the engine, axle/final drive and passenger compartments were very much one after the other.

This is a quick example list of layouts.

Classical rear engine, VW Beetle. The layout is: Passenger Compartment, Axle/final drive, engine. This layout does allow a portion of the passenger compartment to sit above the axle. The engine is relatively easy to access at the back of the car. Historically this layout had good packaging efficiency.

Classical Mid engine, Porsche 550. The general layout is passenger compartment, engine, final drive. This layout is good from a vehicle dynamics point of view but relatively poor for packaging and engine service. It is important to note that the structure of this layout is different than that of a rear engine vehicle.

Front engine: The classical front engine RWD layout is: Engine, passenger compartment, axle/final drive. The significant element is the engine is in front of the driver. There is not a significant change to the generic layout of the vehicle if the engine is or is not completely behind the front axle. Because of this, the term front-mid-RWD doesn't really significantly differentiate the layout from front-RWD. Furthermore, some vehicles which had both an I6 and I4 engine option could be considered front-mid when equipped with one engine and front-not-mid with the other. Several BMWs as well as the Jeep Wrangler and possibly Cherokee come to mind.

As best as I can tell, the front-mid term started as a marketing term. Sports car enthusiasts have come to believe that the mid-engine layout (rear mid-engine that is) is the best layout. Marketing groups realized this and coined the front-mid term simply to capture that name association. As far as vehicle layout the term says little other than we have a classical front-RWD layout with the engine pushed back against the firewall.

I do think the term should either be removed from the article or include some discussion of the idea that front-mid may not be a strict engineering term. I am not adding it at this time because I do not have a reference. Springee (talk) 07:38, 8 April 2008 (UTC)

[edit] FMR Model list

many of the cars listed in the FMR list are described as FR platforms on their individual articles such as:

I would think that the two should match
Compgeek86 20:11, 12 August 2007 (UTC)

[edit] Holden Commodore VE

The presence of a Holden Commodore in a list of mid-engined cars is, I believe, mildly amusing. It's obviously not out of the question though, having a short front overhang; do we have a source on this? 124.176.8.153 (talk) 01:22, 17 January 2008 (UTC)