Just got a 70 Challenger with a 1975 440 engine with no pep at all.  Engine has been rebuilt 2,000 miles ago and is STOCK with exception of headers, Performer intake and Edelbrock 750.  Heads are #452, and Cam is dodge part# P4286675 260 duration, .430 lift, 110 seperation.

I believe the heads are 81.5cc and from what I have found engine compression about 8.2.

Would life be as easy as: new heads with smaller combustion chamber and a good cam?  If so any suggestions?

Thanks in advance!

John

You have good heads, but the rotating assembly of your engine sucks. But the good part is that it is not as much to fix
than new heads would be. And you don't have to take the engine out to do it. Pull the heads and make sure of the bore size,
stock or over bored. Drop the oil pan remove a rod cap and check for over size bearings. Buy TRW six pask pistons,rings
of your choice, mopar steel head gaskets and good pan gaskets.
If it don't have a windage tray get one from mopar. And put
it back together. This will give you a 10:0:1 comp ratio.
Now if you have electronic ignition in your car. And have
a hi po coil of any kind make sure it don't have the inline 1.82 resister on it. Those are for points and the car will
always be a dog with electronic ignition and that resister.
I built my first BB mopar summer 1963 and my last one two weeks ago.  

I think that may be the best option.  I will be opening up the engine over the next few weeks.  I agree changing the pistons and cam should help out a lot.

I will also look into the ignition system and see if there is a resistor in line. 

Thanks!

Here is what I have done:

• Pocket ported the heads, Stainless valves


• New pistons, should have 10:2 compression


• Comp Can XE274H


• Windage Tray


• Edelbrock 750 Performer, Performer manifold, Headers to 2 1/2 exhaust


• 727 Trans w/2400 torque converter and trans go shift kit


• 3.23:1 posi

It does have electronic ignition, with a coil that is rated higher than stock but not the hottest on the marker.  The wiring is all shrink wrapped and I can not see any resisters without cutting all the shrink wrap off, and it really looks sharp!   You said to remove the inline resister (1.82), you are not refering to the ballast resister on the firewall are you?  If that is not it, generally where would I be looking?

Thanks

Is the cam timing to spec? (worn chain or key offset)  

The problem was simple, a 1975 low compression (8:1) engine with a weak cam.  Rebuilt the engine:

• Pocket ported the heads, Stainless valves
  
• New pistons, should have 10:2 compression
  
• Comp Can XE274H
  
• Windage Tray
  
• Edelbrock 750 Performer, Performer manifold, Headers to 2 1/2 exhaust
  
• 727 Trans w/2400 torque converter and trans go shift kit
  
• 3.23:1 posi

And now have about 425 HP and 500+ ft pounds of torque!  Nice cruiser now.

Thanks for everyones help!

kinda light on the gearing,converter and the cam but sounds like a good cruiser.hats off bro