[olaf herrick]

I need some help from one of you well versed motor heads. I'm concidering a 427 SO medium riser motor purchase from a local guy , he has had the motor for 20 years and its been raced a bunch , 3 years ago it was sleeved completly and currently is at 7 thousands over, the machine shop where the motor is has magnafluxed the block and there are no cracks , it has 12.5 to 1 compresion and a wild 700+ lift roller cam,the motor is stroked to a 454 with a 428 crank. The guy told me for my intended street and some road racing use the compression should be dropped to 10.5 to 1 and a 500+ cam installed. My questions is : will a sleeved motor last , with the racing that this motor has seen should I opt for a more original motor or does it all sound OK ? The heads are stock medium riser heads and he will give me a 2 four and single four intake. Thanks for any input.Olaf