2.7 Backdate to 2.4
 

I have a 71 911E garage-queen, week-end driver with a 74 2.7 7R case engine. No history on the engine. Case studs are pulling from the case. Instead of putting $1k in machine work on line-boring and case savers for the 2.7 case . . .

Could I build a 2.4 engine using a used 2.4 case and heads, new or good used 2.4 pistons/cylinders, and assuming all is OK, reuse the crank, rods, cam towers, cams, etc. of the 2.7 in the new engine?

Selling the 2.7 case and heads should be close to a wash on parts costs.

No plans to autocross or race. Just want a strong, reliable, long--lasting engine. Is the 2.4 case likely to need line-boring?

Thanks for the continued help.

JMHO, but ANY mag case needs the "Full Monty" to be reliable anymore due to age & heat cycles.

Its not cheap, bit there isn't an alternative if you want it to be durable.

Line-bore to standard and reface parting lines, case savers, and decking are all mandatory to get a good mag-cased engine so the crank turns freely and doesn't leak.