Paul Walker Crash -- Music Mogul Dumped Similar Porsche -- 'It Was Just Too Fast'

The Porsche GT that Paul Walker was in when he died was just too fast for music producer Mally Mall ... who tells TMZ he had to dump the car because he didn't feel safe behind the wheel.

Mally -- who's worked with Chris Brown, Drake, Tyga and others -- told us he had the GT a few years ago, but sold it because he couldn't control it 100% of the time.

In fact, Mally Mall says the car would sometimes fishtail at high speeds (he once got it to 140 MPh) ... and it scared the crap out of him.