What, if any, are the differences between the 1st gen 12valves and the 2nd gen 12valves, as in differences between the blocks, cranks, rods, pistons, and heads?

 

http://www.dodgeram.org/tech/dsl/Facts/epa_changes.htm

Enjoy the reading

 

Injector pump

and the air intake to the grid heaters is the main thing that i can think of.

Tx

 

The front timing covers are different.

 

Thanks for the link, very informative.

I know about all of the major differences like injection pump, timing cover, injectors, injector lines. But I was looking specifically for differences in blocks, cranks, and rods. The reason im asking is because im going to be building up an all out P-pump motor and I have an 89 short block that needs to be freshened up and a new set of pistons and im wondering if it would be a good canidate or if I should start with a newer motor?

 

the cam shaft in the earlier motor has a different profile. dont remember off hand. the pistons work, though the 89 head i think requires something to install 94-98 injectors but i have seen a few people do p pumps on the 89-93s with no problems. just pump, timing cover and injectors. the 89 and a few years in there the head flows a little less than some of the later ones. compression ratio is the same IIRC.