going to put new heads on my 400 in my 31 sedan and the driver side head came right off, but then the p***enger side will not come off! did everything identical to the other side but it wont budge any ideas? thanks
put a big *** screwdriver in that heat riser hole and push on it a bit. Don't go ******* on it, but levergae helps and the heat riser is a perfect place to insert a BF screwdriver or pry bar
Count head bolts. Are they all out? If so pry under the ledge of the head that hangs over. DO NOT drive anything between the head and block. Sometimes you can get a good pry from the front intake rail of the block over to the non machined or not critical part of the head. Once they move at all they will be free shortly thereafter. DonD
If you have a rubber mallet, you can also pop with that. But, I concur on the screwdriver in the heat riser trick. I'd probably put some leverage on it that way and then pop it with the mallet. Doublecheck that all the head bolts are out, too.
""400s dont have any compression"" Some truth to that Mike but this one does! http://www.olympia-charger.com/2006/07/dolmetsch_built.html I usually did 440s and 383s but accidently got into doing 400s when a racer friend broke his big motor after 9 years of pounding. He didn't have the gold to go nuts so I did a 400 for him we called the 400 cheapy. Stupid thing ran 11.50s off the trailer. That got my interest up and I began to play with these underdogs of the Mopar camp. When asked to do this motor (Lemans) i choose the 400 . .100" shorter stroke than a 350 chevy and a bigger bore than almost any other production car motors. I have decided these motors are sleeping giants and the fact that they do not have compression which you so clearly and correctly stated is what gives them their bad rap. Now that KB makes decent pistons for them (KB240) they make a wonderful powerful and reliable motor. Before that as in the lemans motor I had to have them custom made. Ross did the pistons for the lemans engine and it was limited to 9.6 to one. In stock trim with production tolerences many, in actual fact, arent even 8 to1 even though the specs say they are or were intended to be. They are a very good motor. My favourite displacement for them is 426 (stroking a steel 383 crank slightly till stock piston is zero decked. The lemans motor )which is a real 400 , not stroked)is around 500 HP (not more than 510 and not less than 485 ( best and worst possiblilty calculatd from Ch***is dyno HP test. ) It is a steel headed (452) hydraulic cammed motor) Sorry I got so wordy. As you can tell I have a lot of respect for these motors (now) Anyway back to the issue at hand. i hope you get the head off ok. They are a wonderful motor and highly underated. Don D
I'm not sure why folks bash the 400 B engine, it is virtually identical to the 383 with a change in compression when they were introduced in 72. Compare every aspect between a 71 HP 383 and a 72 HP 400 and the biggest difference will be that the factory simply changed the rating system from gross to net. .
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