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I didn't know where to put this bit of out loud thinking

Has anybody moved the engine back towards the firewall in a 116 chassis (road car)?

I know it's a farely radical sujestion, but at 175Kgs in a relatively narrow car, would it make noticable impovements to turn in and understeer? Obviously it can't be moved far without some serious FW work, tho.

Guys have talked about the improvement from fitting lighter bumper bars and moving the battery to the boot, and I plan to do similar, but these are light compared to the donk.

I do understand the effects of the 'Polar Moment of Inertia', so I can see how the lightening or removal of relative small amount of weight that is the farthest from the cars verticle center can have significant effects, but how about moving the single most heaviest item in the car a small amount (15-20mm)?

It's more theory than anything else, but the engine is coming out and I'm going to make a set of exstractors for her, so the amount of extra work (if it's even close to worth it) isn't massive. But if there is potential for significant improvements in the cars behaviour .

Some numbers calculated from info on on Alfa BB using JJ wheel weight numbers for his road going Verde/75 http://www.alfabb.com/bb/forums/milano- ... ights.html and Fred Puhn's book 'How to Make Your Car Handle'.

Front/Rear weight distribution for JJ's V6 52.2% front/47.8% rear.

The Center of Gravity is then 1310mm/51.57in back from the front wheels and 1200/47.24in forward of the rear wheels.

Polar Moment of Inertia (PMOI) of the engine(385lb) is 1023893.987 lb-in2.

If I managed to move the engine back 1.25in the engines PMOI would be 972923.0665 lb-in2. A reduction of 50970.9205 lb-in2

The difference is about a 5% reduction of the engines PMOI on the car.

A 15kg/33lb battery has a PMOI of 151320lb-in2. Removing the battery from the front left corner of a V6 75 would have about 3 times the effect of moving the engine back 1.25inch.

*Because I haven't calulated the left/right CoG and then measured the distance from the actual CoG (rather than just the front/rear CoG calculation I've used above), the battery's PMOI would be greater than calculated .

Moving the engine back will have an effect but not big enough to justify it on a road car.
A race car with everything else done is another story.
When I swap my engine next time I'll move it back and down. Due to steering design it is not really easy to do.

right spindle on left side and vice versa(tubular LCA's) additional brace between lCArms bmw rack mounted on brace, engine back and down ..... just toughts

oops forgot my favorite pic bloody e30 m3

Actually that is a real DTM body... Bastardized....
4 liter V8 and quite a lot of grunt though.

TS_turbo wrote:right spindle on left side and vice versa(tubular LCA's) additional brace between lCArms bmw rack mounted on brace, engine back and down ..... just toughts

Try holding a right hand upright on the left side and you know instantly it won't work.