RSF

You are correct Sam - the first digit is a 3 not an 8. Based on your info these are obviously not the original heads. Do you know where to find the block number and any others so I can try and figure out what the heck i have in this thing? Comparatively speaking, are these heads decent? The entire motor was rebuilt and the valves and springs were upgraded so i guess that is a good thing.

so after a long delay I finally had time last night to pop a valve cover off and found what I think is the casting number.....8872702. I am a novice and have never done engine work myself so can you guys help me out here? Is there date coding within this number or do I need to compare/match it to other numbers on the block? where would i find the number on the block?

thanks for the feedback! the plugs that are in the car are definitely not the tapered seat style so I am going to pull a valve cover and see what I find. I was led to believe the entire engine was original but I bought it from the 3rd owner so who knows. Assuming I have heads from a 396 - are they better, worse or no difference than the 402 heads??

this MC was built in the second half of '71 and delivered in November '71. Is it possible that it actually has a 396?

I have a '72 MC with the original/rebuilt 402 that I purchased a few months ago and decided to change the spark plugs today. I bought the "correct" AC Delco plugs which are part # R44T. The plugs that came out of the car are NGK R GR5's which are significantly different. According to a little research I have done it seems that the GR5's are for a 396. Can anyone shed some light here??? Thx in advance!!!

Thanks for everyone's feedback. Based on the fact that this is not a simple swap out I have grown to appreciate the 72 front end. The previous owner did a complete frame off resto so the car is so nice I am going to leave it intact.

I understand the premise of backspacing but i am not sure what to go with. I am thinking of 17x8 wheels which typically have either 4.5" or 5" spacing. My car currently has skirts and the stock hubcaps and I will be removing the skirts and going with 66 series rally wheels. Brakes and suspension are stock. Also need to know what size tires will fit properly and not rub.

Has anyone installed 17" Rally wheels? I am trying to figure out what size tires will fit without rubbing.

So what about 72 to 71? Or are all three too different?

Does anyone know how difficult/possible it is to convert the front end of a 72 to a 70? I am looking to buy a sweet restored 72 but prefer the 70 grille and headlight assembly.