Hi all,

Just got a 70 Challenger Convt with a 440! Not original 440 car, started out as 318. Any way looks like the 440 is a 1970, low compression motor with stock cam for a 1974 motor. Car is NOT very peppy. Engine has Edlebrock 750 and Performer manifold, dual exhaust.

I'm thinking heads and a cam would wake up the 440, any thoughts?

What were the combustion chamber sizes in 1970 vs 1974?

From what I've read 1970 compression was about 10.2 vs 1974 compression on 8.2. I have no problem using premium gas as it is only driven to shows and for pleasure.

Thanks for you help!

 

Update:
Here is more info on the 440:
Ø Block #’s 4006630-440-10 dated 2/75
Ø Heads 4006452 believe them to be 81.5cc combustion chamber 2.08 intake/1.74 exhaust
Ø Cam Duration 260, Overlap 34, lift .430, Centerline 110 degrees. I believe this is a very mild cam for my desires.

I am looking to get more pep out of this engine without having to pull it and start over. Heads and cam are a can do, just need to make sure I get the right stuff! Think I need heads with combustion chamber of around 73.5 to raise the compression from 8.2 to around 10.5.

Anyone got ideas?

Thanks

 

Well you have lots of options to improve that performance.

The 452 heads are a very good street head. To really know the true compression you need to pull those heads off and see how far down in the hole the pistons are. Sure you can shave the heads to increase compression. I have seen some fairly potent street cars running in the 8.5 range anyways and the gas is much cheaper[sm=smiley20.gif]

What gears are you running? What converter? Whats the exhaust size? Compression test results?

You'd be suprised on how a good gear set and good street converter and a better exhaust will wake up a car. Also a nice cam/intake combo with a good electronic ignition would help. Also some shaved closed chamber Edelbrock heads would help some also but if your pistons are down in the hole .100+ or more you can only do some much with shaving the heads. If it was me and installing new HP pistons wasn't in the cards I would look at a nice .480+-left / 220-225@.050" duration cam 110-114 LSA . You can't really go much bigger of a cam with low compression or it would just be overkill. (Sound good, run crappy). Maybe a good Edelbrock Performer intake, a good breathing 2 1/2" exhaust, the proper rear gear set (3.55+-)and maybe a nice 2500-2800 stall converter if you are running an automatic. If its a 4spd then thats not an issue to deal with. You can do some of that or all of that, but work out a plan so all the pieces you buy will compliment each other.

Also doing the basics helps to start with. Timing! Carb tuning! Etc.

Good Luck![sm=smiley20.gif]

Chris

 

I've been wanting a set of the Edlebrock RPM aluminium heads for my 440 and I recommend it for yours. What exhaust is on it, stock, stock with headers, etc.? Mine really woke up when I put the headers on and a full 3" dual exhaust, but my 440 has more done internally. Headers and at least a 2 1/2" dual exhaust is the only way to go with it.

 

Already have Performer manifold, 750 carb, headers with 2 1/2 exhaust and 3.23 rear end.

Will be getting 2200-2400 ish torque converter and trans-go shift kit in next week or so. I'll also be pulling the engine and changing pistons & cam. Looking to run 10.0 compression, mild pocket porting on heads and cam looking at something like .488/.491 lift .230/.236 duration with lobe seperation of 110.

I think this should net me about 400 HP, keep it reliable without much overheating, I live in the desert and heat is a problem about 7 months a year!

 

Go with Edelbrock heads too! To redo your stock iron Mopars properly will cost almost as much. The Edelbrocks will run unleaded but you will have to do hardened exhaust valve seats if you want to flog your motor and expect it to last.