440 more snot

[dodgey68]

hello dc.com.
I have recently  fitted a 440 , specs ,30 thou over, 6pak pistons, closed chamber heads,edelbrock  performer manifold, holley 770, bit of a cam, electronic ignition, try-y headers, , diff gears recommend, for a good cruiser/ performance 
what else can I do to get a bit more snot, $$ just asking  ideas 

[BSB67]

The list of parts gives a good idea of how a car should perform, but does not necessarily define how it actually performs.  So the first question that I ask is:  Is it currently performing like it should?  Said differently, if your motor is suppose to make 425 hp, the question is: does it?

Track data is the best data for determining car performance, and diagnosing if there is something amiss with what you have now or not.  Do you have track data?

Tell us more detail about the heads and cam, as these are the key components.

Assuming what you have now is dialed in and making the power it should, you can screw around with carbs and exhaust and maybe get a little more power (may or may not be noticeable), or you can screw around with converter and gear to make it feel snappier at lower speeds.  To make a noticeable step change in power, it is heads and cam.  

[ACUDANUT]

I read somewhere here that  " 6pak pistons" were heavier and added nothing in the HP world. ?   

[BSB67]

The factory replacement style 6 pack pistons (L2355) weight about the same as other standard factory pistons.  Piston weight reduction would not be a logical place to look for better performance on an already assembled engine without doing a lot of other things first.

[firefighter3931]

Where is the timing set ? Base timing ? How much mechanical advance ? At what rpm does the timing stop advancing ?

A lot of power and drivability can be found with tuning.....and it all starts with the ignition system. 


Ron

[Challenger340]

hello dc.com.
I have recently  fitted a 440 , specs ,30 thou over, 6pak pistons, closed chamber heads,edelbrock  performer manifold, holley 770, bit of a cam, electronic ignition, try-y headers, , diff gears recommend, for a good cruiser/ performance 
what else can I do to get a bit more snot, $$ just asking  ideas 

6pak pistons, closed chamber heads

Say what ? 
Correct me if I am wrong here.... but L2355 and "Closed" Chamber Heads ?
You might have a bit of squeeze there to deal with ? on cast iron "Closed" chamber heads ?
What Camshaft ?
More info please.

[fy469rtse]

Yep ,
More info please ,  if you have the six pack rods , heavy rotating mass , don't expect anything startling ,
Diff gears 3.55's on the street to 4.11's , last one just high reving if intend driving at 100klm, but good of the line

[dodgey68]

diff gears  2.76 ratio, its high, good  for cruising and fuel,
but whats a good all round ratio,,  what you guys reckon

[fy469rtse]

3.23  good ratio from factory 3.55 's is what I currently have ,
Not bad on the highway rev wise,

[dodgey68]

i have gotton hold of a 3.23 diff centre , should that pep it up from the current  2.76

[fy469rtse]

Yep , you will defiantly notice a difference, 
But like the guys have said , timing and tune can make a huge difference

[garner7555]

Yes you will notice a difference with those gears.  My car had 2.76s originally too.  Best thing about 2.76s was how it would spin the tires so fast that really long burnouts were easy, even with a worn out 383.       I too have 3.23s ready to go in my car at reassembly.   

[dodgey68]

i have been driving the car, I get around 11.6 mpg,,   hows that

[fy469rtse]

is that KLM or miles , new diff centre in ?

[dodgey68]

miles and with the 2.76 ratio,
I know  once the 3.23 is in it will decrease but I didn't build it for fuel economy