sixpack71

ihave a 71 roadrunner, it has a 71 400 block in it (casting number 9-8-71, 3614230-1) my hood reads 383, and my vin number says it came with a 383, i was wondering if they came out with 400 blocks as an option later?? any info would be appreciated!

72RDRNR

72 was the first year for the 400. Sounds like someone installed new engine, but the 400 is a very good motor and lots of parts available to build them - stroker kits!.

Polaradude

3614230 is indeed the 400. This casting # was produced in 71 & 72 and is a B block.

67 GTX

the casting number means the date it was casted
if it says 71, the block was probably first used in a car in 72 or 73

chlngr1970

To add to the above, the 400 is in the same engine family as the 383. IIRC, it goes 350, 361, 383, 400. Then the RB engine ( Raised Block...taller deck hight ) was the 413, 426 wedge and 440. Depending on what you want out of your car, the 400 might just be perfect for you.

j

67 GTX

what are your plans?