Forging is alright and all, but are you planning to make a ton of these to warrant the tooling? I'd imagine at somepoint it'll be worthwhile to tool it up for forging, but if you are not making a ton you might be better off just welding tubular styule a-arm....
Not sure what the fidelity of the CAD model is, so maybe you've omitted some details. But that rear box does not look very stiff especially if you are running pull rod layout where most of your load will feed through upper ball joint and the upper a-arm, the rear suspension pickup "box" is not closed off?
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