440 advice needed

[willard]

Last week we checked my friend's 78 440 that he has in a 72 cuda. Car is auto w 2.76 gears (for long distance cruises) and of course it drives almost like my old low comp 383 in my challnger.
So we pulled one head (452s) and it measured 85cc and is in good shape with dual springs and modern valve seals installed.

The goal of my friend is to have some 450 hp but still retain wise MPG as gas isn't cheap in Europe. The engine already has headers, stock iron manifold, 750 holley vac sec.

The pistos are more less 0.15" down the bore and are 4.32" there is no evidence of any markings on the tops so I assume these are factory low comp pistons.

We though about just swapping the pistons to KB237 and camshaft to something w approx 0.500 lift and 230 duration @0.050, maybe mopar 509?

Please take a look at the pictures - do the lobes look very worn out?
What ya think?

[Cooter]

The 1977-78 440 was a pig...Rated at just a bit over 230 HP...Yep, gonna have to swap out the pistons and rebalance the bottom end to get the comp. back up to respectable..Cam appears to be ok from the pic...

450 HP 440 and fuel mileage don't even go in the same sentence....

[HP2]

Biggest improvement you can make, power and mileage wise, is to increase the compression ratio. The more you squeeze the charge, the more efficient it becomes. However, the ratio you choose is also going to depend on the camshaft you want to use as well. The cam will determine the power band range, then you build teh compression ratio to match the duration of the cam.

With that, decent mileage figures and high torque vaues will still be possible. I'd recommned you chase maximum torque in the range you drive in rather than get too hung up on horsepower numbers. An engines torque peak is also its volumetric efficiency peak. So if you use too big of a cam and your max torque is at 5000 rpm, then your cruising miles per gallon will suffer, but you will have a lot of horsepower. By contrast, if your torque peak is under 3000 rpm, then you get massive amounts of torque down low in the range you normally drive in, but will give up some horsepower on the top end.

FWIW, the 440 in my truck gets almost 20 mpg and can pull a load like a diesel using this approach. But, it is running out of power overrpm.

[willard]

The way of thinking presented by HP2 is the closest to my friend's plans. I doubt the engine will see more than 5k rpm. It has to be a nice cruiser but when floored it should show other people what mopar is.

.528 lft is also acceptable but I dont know the duration of this cam. I guess we dont need much overlap and very long duration.

[Moparal]

Couple of things Willard.  Don't you mean 150 thou in the hole?  If 15 thou in the hole, that is better than kb 237's which are like 20.  Also, I have never seen a 452 head cc out at 85 cc's.  By the way, your stock pistons I see in the pic look like 150 down if any of them are at tdc.

[willard]

Hi Al,
The heads have been milled and we cced them with a syringe: we had one chamber at 85 another at 84 cc. Casting is 452.
Our measuring tool was a simple digital caliper and no 4 piston was at TDC and it was definitely 0.15" down the bore, not 0.015".
I did some math with KB 237 CH and they should be somewhat 0.015" below the deck and are +5cc with CH=2.067". The KB 236 are only +1,8CC but with CH of 2.057 will be 0.025" below the deck.

[Chryco Psycho]

I would use a modern cam grind like the Lunati Voodoo over the 35 year old Mopar cams , the 509 is long duration without much lift ,you won`t be happy with that

[willard]

I have lunati 60302 in my 383. Which lunati cam would you recommend for this 440?

[Chryco Psycho]

will you bring the compression up ?

[willard]

of course! we plan something between 1:9,5 and 1:10 static.

[Chryco Psycho]

I would look at the the 60303 or 304 if you are staying hydraulic cam

[willard]

Will these cams work right with a stock torque converter?

[Chryco Psycho]

I would recommend a higher stall converter than the low stall stock unit

[willard]

He'd rather stick to the stock t/c. What is a guestimated tq/hp with 9,6:1 CR, headers, 750DP, 452 heads with stock rockers and iron stock intake with lunati 60302 ?

[73restomod]

With Highway gears i would stay away from a Mech secondary carb like a DP. A vacuum secondary will perform much better and if you lean out the primaries reasonably, and richen the secondaries you will get the best combo of mileage and power.