singledownloop
singledownloop New Reader
1/1/15 3:48 p.m.

In a mid engine car how much engine offset is possible with the engine in the north-south position without negative effects.The engine weighs 600 pounds.I want to offset it to the passenger side.

Kenny_McCormic
Kenny_McCormic PowerDork
1/1/15 3:57 p.m.

How far do you plan? Assuming an already balanced (when empty) car, a 200lb driver with the center of the seat 15 inches from the centerline of the car, a 600lb engine offset passenger side by 5 inches would actually balance the car left-right. It's a simple "see-saw" calculation. I have no idea how far you can get the COG off the centerline without noticeable effects on the handling.

EDIT Also, you can only go so far off on a longitudinal mid engined car with a transaxle before you run into issue with the offset transaxle interfering with suspension, or CV angle problems if you put it on an angle.

Knurled
Knurled GRM+ Memberand PowerDork
1/1/15 4:01 p.m.

Take a look at any production car sometime, you'd be surprised how offset the engines can be. Or how off-axis the drivetrains are.

I think the RX-7 has the shifter on the right side of the car but the front of the engine is five inches to the left.

singledownloop
singledownloop New Reader
1/1/15 4:12 p.m.

Track width is 57",wheelbase is 104",total weight without me 2800 pounds,I weigh 150 pounds.I have the how part of the engine offset covered I just need to know how much is acceptable without negative effects.If any more info is needed I'll try my best to provide it.

Knurled
Knurled GRM+ Memberand UltimaDork
1/1/15 4:48 p.m.

What else is back there? Battery, reservoirs, anything?

600lb engine in 2800lb car means there's 2200lb that isn't engine. I wouldn't sweat it all that badly.

Going back to the old RX-7s, the left side of the car had the engine, the battery (as far forward/left/up as Mazda could put it!), the steering box, the steering column, the pedals assembly, most of the wiring, the A/C compressor and power steering pumps if equipped, the fuel tank, and the driver. The right side had... the exhaust system and the A/C evaporator box, which was plastic.

They still seemed to handle okay, even after people took off the heavy OE exhaust for a lighter one.

singledownloop
singledownloop New Reader
1/1/15 6:21 p.m.

Thanks guys appreciate the knowledge

mad_machine
mad_machine GRM+ Memberand MegaDork
1/1/15 9:36 p.m.

yes.. look at the X1/9. Same idea, mid-engine car. That little 4 was stuffed into the far right side of the engine compartment with only the driver and gas tank to offset it. (even the spare was on the passengerside of the car, behind the passenger seat) and the X is -still- considered a damn fine handling machine

patgizz
patgizz GRM+ Memberand PowerDork
1/1/15 10:35 p.m.

fiero - all iron v6, quite to the right.

Kenny_McCormic
Kenny_McCormic PowerDork
1/2/15 12:22 a.m.

Do keep in mind that a transverse engine car has the trans on the other side, and often the battery mounted above the trans. I wouldn't doubt it if a X1/9 is pretty well balanced left/right with a driver.

RexSeven
RexSeven UberDork
1/2/15 1:01 a.m.

There's a Modified-class-turned-hillclimb car in the Project cars section with its frame and engine heavily offset. The owner says while it's a little left-heavy weightwise and probably turns left a little better than right, it's not very detrimental to the handling (it's also one of the most badass cars on the forums!).

http://i1281.photobucket.com/albums/a511/kevin_gale1/100_0686_zpsb8667099.jpg

Knurled wrote: Going back to the old RX-7s, the left side of the car had the engine, the battery (as far forward/left/up as Mazda could put it!), the steering box, the steering column, the pedals assembly, most of the wiring, the A/C compressor and power steering pumps if equipped, the fuel tank, and the driver. The right side had... the exhaust system and the A/C evaporator box, which was plastic. They still seemed to handle okay, even after people took off the heavy OE exhaust for a lighter one.

Perhaps JDM (right-hand drive) RX-7s have better left-right weight distribution?

mr2peak
mr2peak GRM+ Memberand HalfDork
1/2/15 2:03 a.m.
RexSeven wrote: There's a Modified-class-turned-hillclimb car in the Project cars section with its frame and engine heavily offset. The owner says while it's a little left-heavy weightwise and probably turns left a little better than right, it's not very detrimental to the handling (it's also one of the most badass cars on the forums!). http://i1281.photobucket.com/albums/a511/kevin_gale1/100_0686_zpsb8667099.jpg
Knurled wrote: Going back to the old RX-7s, the left side of the car had the engine, the battery (as far forward/left/up as Mazda could put it!), the steering box, the steering column, the pedals assembly, most of the wiring, the A/C compressor and power steering pumps if equipped, the fuel tank, and the driver. The right side had... the exhaust system and the A/C evaporator box, which was plastic. They still seemed to handle okay, even after people took off the heavy OE exhaust for a lighter one.
Perhaps JDM (right-hand drive) RX-7s have better left-right weight distribution?

That's a great thought!

evildky
evildky Dork
1/2/15 1:01 p.m.

With the MR2 I "Centered" the engine left right with the cv shafts I was planning to use, this kept me from needing custom parts. I did however push the engine as far back as I could to take as much driveshaft angle out as I could (also height) I did this to keep the CV's as straight in the tulips as possible. The popular theory is that bottoming out the camry CV's caused breakage I suspect the angle had more to do with ti and mine survived hot lapping at the drag strip.

mad_machine
mad_machine GRM+ Memberand MegaDork
1/2/15 3:59 p.m.
Kenny_McCormic wrote: Do keep in mind that a transverse engine car has the trans on the other side, and often the battery mounted above the trans. I wouldn't doubt it if a X1/9 is pretty well balanced left/right with a driver.

I can't tell you for certain on the X.. only that the battery was centered in front of the windshield on those cars and that engine was shoved all the way to the right to make for equal length drive shafts.. so I expect the transaxle is centred, negating it's weight, but that still leaves a heavy iron block all the way on the right with the heavy full sized (abet 13") spare right in front of it

Kenny_McCormic
Kenny_McCormic PowerDork
1/2/15 4:10 p.m.

How much does a fiat SOHC really weigh though? I doubt its over 300lbs.

turboswede
turboswede GRM+ Memberand UltimaDork
1/2/15 5:02 p.m.

In reply to Kenny_McCormic:

Not very much at all. Here's a 1500 in the trunk of Mezzanine's SAAB 99 after placed it in there harnessing the power of two average computer nerds :)

singledownloop
singledownloop New Reader
1/2/15 5:19 p.m.

This isn't a transverse mounted engine.The engine is mounted front to rear.....

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