440 six-pack crank and rods

[Mecki]

I'm starting to build 440 six-pack engine using parts collected over the years, but first I want to clarify some things about the six-pack engines.

Was it so that when the six-pack engine first came in 1969 it had the same internally balanced crank as all the other 440 engines starting from 1967 used(part 2536983)? Were the rods also same (part 2406770, casting 1851535)? What would be a reasonable rpm and power limit for this setup?

The later six-pack rods (part 2951906, casting 2951908) came in 1970. As I understand this rod can only be used together with an externally balanced crank (part 3512036)? The rod is stronger but also much heavier so can you rev it more than the standard? Is the crank stronger or is it just the balancing due to heavier rods witch is different from the standard crank?

If the rods are the weak link, then a setup using a 67-70 standard crank together with aftermarket replacement rods like 440source Part No: 200-1015 would probably be a good choice?

Just found the 440source.com page today (someone mentioned them here). Lots of parts and information. Any comments?

[John Kunkel]

The '69 used the same LY rod as all RB engines since day one (except the Max Wedge). The '69 and later 6-pack cranks are visually no different than other 440 forged cranks, hardening and shot peening make them more durable.

The '70 and later cranks need external balancing due to the added weight of the rods and pistons. The crank can be internally balanced using heavy metal but the cost is way out there. Nowadays most consider the heavy rods overkill, while possibly less prone to breaking, their added weight causes its own problems; if using a factory rod, the LY with polished flanks and a good set of aftermarket bolts fits most needs

440source has good products at reasonable prices, some will turn their up noses to anything Chinese but their products have proven to be a good value. Like they say, considering the cost of refurbishing the fatigued factory rod the 200-1015 is a good buy.

[Mecki]

Hi John. Thanks for your reply.

So what you are saying is that the -69 440 six-pack internally balanced crank is not exactly the same as the one used in -69 440 4bbl engines. That internally balanced stronger (hardened) crank can then be found in -69 six-pack engines only, right? I'm asking this so thoroughly because I happen to have a -69 440 4bbl engine and a -69 six-pack intake with carbs and I was wondering if this setup would be exactly the same parts as used on the -69 six-pack engine, except the camshaft of course. Would be nice to have a "factory original" six-pack engine.

Anyway I have a couple of 440 4bbl pre-70 cranks with LY rods so I will stick to them for now and I'm really not so interested in those externally balanced setups. I will probably restore two engines simultaneously, the other close to stock six-pack with hydraulic lifters and the other...lets see.

Any idea of reasonable maximum rev, cr and power / torque output for these cranks and rods? It helps to know what the realistic limitations for the lower end are when you select cam, oiling, bearings etc. Maybe 6000 rpm is what the rods can do or am I already pushing my luck?

Are those 440 source new production parts China made??? Really??? Not that I have any prejudices but...

No really. I have to admit that I have had to reconsider my opinions about Chinese steel industry. The level of quality and finish is something totally different from what it was some 10 or 15 years ago. The labor costs are still low and they have realized that it pays of to invest in quality. But to put it into a Mopar

440 source seem to have lots of used parts in stock too. Any comments on the pricing and condition of the stuff. It's always gambling when you order used parts, especially when it has to be shipped overseas. The shipping costs are about the same as the price of the parts so whats the point to send them back if they turn out to be junk or just wrong.

[Paul Precht]

I run the stock rods about 7,200 through the traps, Paul.

[Mecki]

OK, thanks Paul. Running a hydraulic cam would then put the limit to rpm before the crank/rod setup. Second thing would be what pistons I'm going to use. If I go with the stock pistons that will then probably put the limit even lower?