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Checking my information: 71 440 steel crank internally balanced? "HEAVY" rods?

So
All 6 pack external
most 440hp with forged crank external
It would shake
if it ain't broke don't fix it
given a choice use the LY rods, MP/SPS bolts and internal balance- and LIGHT pistons
 
It would shake
if it ain't broke don't fix it
I would say that's the key....
My plans have been to take the aluminum 6bbl intake and Holley carbs and TTi headers off the engine, "fog" the rest and start from scratch with a stroker motor, so I wouldn't be using the crank, rods, block, heads, or pistons anyway.
 
In my bracket motors I ran LY rods or in my first low deck 400 rods with 440 crank. I always had them shot peened & used SPS bolts. The 6 BBL takes some tuning effort, but sure can work really well.
 
Exactly what I ran on my 383 and 400 low blocks (back when aftermarket stroker cranks were really pricy) Just ran across an Arias build sheet for an early 383 stroker (stealth - stock looking) stock heads, manifolds, carb Crower cam with a little shorter than magnum seat durations but lots more lift/ area so it idled stock it think it was 218 by .050 on the intake
 
given a choice use the LY rods
LY rods are different than 6 pack rods, right? And the difference is?
I have Eagle H beam rods on my mental parts list, and an Eagle stroker crank, both with their proprietary ESP armor treatment. I AM open to best quality and strength options. Like I always try to do-Once-One and Done with no "if only_____" or "I wish_____"
My stroker will likely be over built, unless someone (like IQ52 or wyrmrider) tells me to scrap my plans to keep my good running current motor as a backup and have it rebuilt with a clean up bore, new slugs, and with new parts capable of handling a 250 shot or so of Nitrous.
 
The six pak rods have a wider center web like a Hemi rod, but not as well finished. LY's are the standard 440 rod. The modern parts are much better. Eagle H beams seem to be really good. That's what are in my 512. When I was bracket racing in the '70's & '80's no reasonably priced aftermarket parts were available. For my bracket racing situation I found a spare motor was very helpful.
 
LY and 6 pack rods are standard steel
Hemi rods and the longer NASCAR rods, there were several are chrome moly
that said LY rods are good for most street builds with SPS or ARP bolts i side grind, mag, shot peen and rebuild
but today check out the aftermrket rods if they are chrome moly
for stock stroke run a longer rod if you can- hemi length or longer gives a lighter piston
stroker run as long a rod as you can- same reason and less cylinder wall loading
there are trade offs short rod vs long rod say in a 400 with a 440 crank but for almost all application long rod wins
 
stroker run as long a rod as you can- same reason and less cylinder wall loading
Is a "long rod" stroker a common combination?
What would an example of bore/stroke/crank/rod length be that you would consider ideal?
My stroker has to get me through the 1/4 mile in 4th gear (5 speed) with a 4.10 R&P so that would be the RPM requirement.
I can't give you the RPMs yet because I haven't made a full 1/4 mile run with the new R&P yet. Reasonable estimate is 5,800
 
My 512 has 4.25 stroke & 7.10 rod. Seems to work. I've built stock 440 crank/rod (6.76/3.75), 6.36/3.75 low deck, 6.76/3.75 low deck as well. The 4.25 stroke with 7.10 rod is very common. Fortunately Mopar blocks are very hard/stiff, so they can take a bit more side load. Thicker cylinder walls make more power & hold up better. Check the bore thickness.
 
good advice above- work with a proven combination
I just did not like the 440 crank with stock 400 rods combination
or the Jeep 4.0 with stock 258 crank and short rods and stock 4.0 pistons combination as the piston ended up too far down the hole
 
FYI, back in the day when parts weren't available, my low deck block, cut down 440 steel crank, 400 rod, 13.2 Arias piston was my most powerful, good running motor. The stock crank was not up to the RPM it was running. I should have changed rear gears sooner. IMHO
 
13.2 must have been back in the good gas days
actually that is one of the "benefits" of the short rod motor- the pistons spends less time around TDC and moves down the bore quicker
so while it does not give as much force; it does it quicker with slightly less detonation problems
remember heads would be optimized differently for short rod vs long rod on an all out motor and the cam should be different for any build short vs long
you add up a few degrees different on opening and closing, ICL excl, (lobe centers) and it makes as much (or more) difference than advancing or retarding 4 degrees- which is something that most of us know does make a difference
most camgrinders list shelf cams with same timing as the popular short rod motor...
 
Well, 110+ gas was available. My heads were 906 or 915 ported by me. The intakes were ground through the push rod lump & epoxied on the outside. I ran a 690 284 roller & my favorite 635/645 mushroom cam. Both were 108 centers. I sometimes advanced them 4*. My 400/452 ran pretty good in the day. Lots more power can be made today.
 
Not all heavy-duty rod motors were externally balanced. The only original partially externally balanced forged crank 440 HP’s were ’71-72 six packs with HD rods AND heavier six-pack pistons (10.2:1cr). All other forged crank motors with HD rods and low compression pistons were internally balanced. All cast crank configurations are externally balanced, with heavier counter weighting than the six-pack combination.
 
(no determining stampings on the pad by the distributor

.

There are no stampings by the dist pad on a 440. They are on top front of the engine ahead of the intake on the drivers side. You probably know this but others may not.

Screenshot_20180917-124553.jpg
 
There are no stampings by the dist pad on a 440. They are on top front of the engine ahead of the intake on the drivers side. You probably know this but others may not.

View attachment 654707
Thank you. The area indicated by your arrow is what I was referring to. No "HP" or Maltese cross, etc.
I would have to look again to try to discern what stamping(s) are there, but when I did that early on nothing was "decipherable" as having any meaning.
Since I don't notice any problems with the billet steel flywheel replacement, nor any discernable vibrations, I am just going to leave it be.
When I replace the motor with a stroker, I am only using the intake manifold, carbs, and headers and fogging the rest. I may pop the pan and have a look-see then.
 
thanks for the tip 72RR
I've never seen an internally balanced low compression heavy rod motor
but after the early 70's there were all kinds of weird combinations
 
I’ve seen many low compression 440 HPs with HD rods, forged cranks, and full internal balance. In the mid later seventies, used to pick-up retired Oregon State Patrol cruisers for a few hundred bucks from state surplus auctions. Usually ’73-74 Coronets with low compression (8.2:1) 440HPs. With very well-maintained 100k highway miles. All had forged cranks, HD rods and internally balanced. Swapped one into the numbers matching (not that it mattered at the time) ’70 383 Road Runner I had then, sold the Coronet with the 383 in it at a good profit.
 
So
All 6 pack external
most 440hp with forged crank external
It would shake
if it ain't broke don't fix it
given a choice use the LY rods, MP/SPS bolts and internal balance- and LIGHT pistons


I personally removed and tore down a mid '70s motorhome 440 that had 6pack rods, low compression (lighter) pistons and a steel crank with NO balance weights on the torque converter or an offset weighted balancer. The crankpin cheeks were machined at the front and back (where they are drilled) to lighten them even more. I thought that was really odd, but it was factory.
 
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