Exactly what the title says. I might be picking up a rebuilt 390. the owner says its a 1967 390 police intercepter. But the 390 PI was not produced in 67 so i think its either a GT or regular 4v 390. so when i go to look at it i plan on removing the cylinder heads just to check bore and stroke but how can i tell what performance package (?) this engine has? Thanks.

 

RebelMike, there is not a lot of differance to be seen. Some of the 390s have a differant pattern drilled into the exhaust flange so that they could be dropped into a mustang or fairlane. The block and crank/rods and heads would all be ordinary stuff. The 390GT SHOULD have pistons with a smaller dish than normal, but so should any 3904V. If it has been rebuilt, who knows what pistons were used ? Unfourtunately there are a lot of rebuilders out there who don't seem to realize that 390 cars and trucks recieved differant pistons from the factory. Then they put the truck pistons in a rebuild in a car and wonder why they don't have enough compression. A 390 PI SHOULD have a very nice dual plane aluminum intake on top and if a 390GT the cam is a little bigger (280/290) than ordinary. DF

 

Thanks for the info, so if its a PI it should have a aluminum intake. and the heads should have a horizonal and vertical intake. thanks for the info.