1970 440 engine v 1974 440 engine, what's the drawback?

[CB]

Sorry to ask this Q here but needing a quick answer.

If you compare a stock '74 440 against a stock '70 440 (original Charger engine) what do you have?
(1970 Charger lost his original engine and now houses a '74 440 with Weiland intake and headers and a hotter cam)

I imagine you lose lots of power caused by the de-tuning of the engine?
How much can it be compensated by changing the cam/intake/carb/headers set up?



Thanks for the info CB

[John_Kunkel]

The biggest difference is the compression ratio....'70 was advertised as 9.7-1 and '74 was 8.2-1. It's hard to get a low compression to perform.

[Kern Dog]

Tell that to Jim LaRoy....
He did a low compression 440 dyno session awhile back and it still made lots of power. Sure, being down almost 2 points isn't optimal but you can still make 400 HP with the right cam and heads. There are new aluminum heads with smaller chambers than the iron heads, this bumps compression up some.

[heyoldguy]

I keep going back to this engine build we did on a low compression 400 that builds almost as much power as a 440HP. What if we had installed a set of service prepped (pardon me Challenger340, but your "prepped for service" description is right on the mark) Stealth heads on it? Because I'm one who doesn't buy the notion that aluminum heads on low compression engines hurts the performance.

http://www.forbbodiesonly.com/moparforum/showthread.php?80843-The-slug-400-on-the-dyno&highlight=400+2bbl

[Challenger340]

IMO, it's not that just dropping a set of Aluminum Heads on a low-pop motor won't make more power... sure it will.....  but in conjunction with the correct Cam events and the extra Flow to take advantage ?, all things are possible.
But,
My only contention for the average DIY guy to doing so is versus "money spent" for the gains achieved ? versus rpm req'd ? versus "tuning" on a current "low-pop" Piston deal, that invariably still has Pistons .100" the Hole(quench issues), etc., etc.
It's just me, and only my opinion here ? but balanced against the way I feel I need to deal with my customers and run my business ?
Why Bother versus money spent ? for the average DIY guy ? so I don't perceive it as a recommended "fix" they will be happy with long term.

[John_Kunkel]

Tell that to Jim LaRoy....
He did a low compression 440 dyno session awhile back and it still made lots of power. Sure, being down almost 2 points isn't optimal but you can still make 400 HP with the right cam and heads. There are new aluminum heads with smaller chambers than the iron heads, this bumps compression up some.

Using that same train of logic, why us a V8? You can get 400 HP out of a /six.

[Kern Dog]

Who wants the sound and vibration of a 400 HP slant six???

[heyoldguy]

IMO, it's not that just dropping a set of Aluminum Heads on a low-pop motor won't make more power... sure it will.....  but in conjunction with the correct Cam events and the extra Flow to take advantage ?, all things are possible.
But,
My only contention for the average DIY guy to doing so is versus "money spent" for the gains achieved ? versus rpm req'd ? versus "tuning" on a current "low-pop" Piston deal, that invariably still has Pistons .100" the Hole(quench issues), etc., etc.
It's just me, and only my opinion here ? but balanced against the way I feel I need to deal with my customers and run my business ?
Why Bother versus money spent ? for the average DIY guy ? so I don't perceive it as a recommended "fix" they will be happy with long term.

True, much better to design an engine than to scab one together. Sometimes an engine owner's "learning curve" is more like a sine wave. If they cannot listen it's, "Damn, I wish I would've done.............................."