Did 440 4bbl 375 horse motors get 6 pack rods?

[66 Monaco 500 365]

I've rebuilt a few HP 440s in my time, and only one, a 1972 Polara CHP 440 4 bbl had 6bbl rods.
I watched an old YouTube vid today from Nick's garage and he said that "most" '70 375 horsepower E body 4bbl 440s get 6bbl rods.
What is your experience with B or E body factory 440's?
Did 70 or 71 4bbls get 6bbl rods?
Thanks for the info!
Scott

 

[413]

I’d say the 1970-71 B and E bodies 440-4 all got 6bbl rods and balancer.

 

[furious70]

We had one that did.

 

[57fury440]

I think the "six pack rods" came out in 1970. The 1969 six packs had the standard 440 rods. The earlier motors did too.

 

[saforwardlook]

I think the "six pack rods" came out in 1970. The 1969 six packs had the standard 440 rods. The earlier motors did too.

The six pack engines were introduced in mid-1969 and all subsequent 440 HP engines got the six pack rods, even the C-body models. Here is a summary on the topic from Hemmings................

https://www.hemmings.com/stories/article/chrysler-440-six-pack

I do have a 70 Cuda 6 pack and that thing is downright dangerous in the wrong hands especially with its very light rear end compared to the front end. For those who haven't seen it before, here is a photo of the one I restored many years ago now......................................

It still looks the same today as in the photos since I don't drive it that much given how tempting it is and it rides like a buckboard compared to our C bodies. It also has a 3.55 rear end that doesn't help things either when driving down the freeways and the engine is spinning at pretty high revs in that mode too. But its stock exhaust is still pretty quiet but not as quiet as C bodies.

 

[Big_John]

The six pack engines were introduced in mid-1969 and all subsequent 440 HP engines got the six pack rods, even the C-body models. Here is a summary on the topic from Hemmings................

https://www.hemmings.com/stories/article/chrysler-440-six-pack

Hemmings is wrong.

The 69 1/2 6BBl/Six Pack engines had the same pistons, rods, crank and balancer as any other 440 made that year. I built a bunch of engines for 1969 and helped build some for 1970 NHRA stock class cars. There was some hype that the internals were hand selected and rods magnafluxed etc., but I've always taken that with a grain of salt.

In 1970, the 440 6BBL/Six Pack went to the heavy (junk) rods with the external balance harmonic balancer. That engine also had a piston with valve notches and a higher deck height. In fact, a friend got bounced after winning stock class at Bud's Creek because he had 4bbl pistons in his '70 6BBL Roadrunner. (I had nothing to do with that engine) . I found some NOS correct pistons for him and we built a correct engine.

The problem is there was so much misinformation about the 69 1/2 cars versus the 70 cars. The magazines didn't help as they spread a lot of that misinformation.

The heavy rods showed up in other, post 1970 engines, including some cast crank versions.

The heavy rods were junk... Every 440 I've ever seen that had a bad rod was a heavy rod engine. IMHO, it was just too heavy for its own good.

These were mine.

 

[Dutchrebuild]

70-71 440hp engine got the heavy rods and special balancer. 72 and up to at least 75 440hp engine also got the heavy rods, but not the special balancer. I have taken apart many 70-75 non HP 440s that were in heavy duty applications that had the heavy rods, steel cranks, and windege trays, but no special balancer

 

[cuda hunter]

I have a 69 warranty 440/4 that came with 6bbl rods.

@saforwardlook Just curious, you said restored, The shaker is yellow, the rear bumper is a painted bumper and the interior door panels are for a gran coupe. Was your car originally a BP car and just had a few liberties taken? Probably an N code?

 

[57fury440]

I agree with Big_John completely. The six pack rods were junk. The speed shops and their machinists I delt with back in the late sixties to early seventies advised me to get rid of those rods. I have never had a problem with the standard rods in any of my big block engines including a six pack.

 

[69CoronetRT]

Hemmings is wrong.


The problem is there was so much misinformation about the 69 1/2 cars versus the 70 cars. The magazines didn't help as they spread a lot of that misinformation.

I agree.

Factory documents are always a great place to start to clear up repeated misinformation or clarify applications.

The 1969 6bbl rods carried a different part number than regular 440 rods. (Notice there is no difference in standard PN 2406770 440 rods or HP application for 1969. Rods are rods). The PN3462426 were treated differently than other 440 rods (Were they magnifluxed? Still trying to find the documentation as to why they have a different part number)

So for 69, there are "six pack rods" as there were rods specific to the 6bbl assembly.

In 1970, and 1971 as applicable, the same rods used in 1969 HP and non HP applications are listed as the correct rods for 1970 NON HP applications. PN 2406770

There are rods listed for orange HP applications for 1970. This would include both 440-4bbl and 440-6bbl applications. PN2951906

So for 1970 and 71 (72?), there really are no rods exclusive to a 6bbl application.

The term 'six pack rods' can really only be applied to the specific application rods for 1969.

 

[saforwardlook]

I have a 69 warranty 440/4 that came with 6bbl rods.

@saforwardlook Just curious, you said restored, The shaker is yellow, the rear bumper is a painted bumper and the interior door panels are for a gran coupe. Was your car originally a BP car and just had a few liberties taken? Probably an N code?

My car was an original 33K mile Cuda with its original numbers matching 6 pack engine in it and its original VIN was still in place verifying its original 6 pack status. You are correct, as the shaker bubble was normally argent silver but I preferred yellow to more easily keep it looking clean. The problem with the car is it was missing its body code plate so I just built it as I would have optioned it if I could have since the missing body code plate (and no build sheet either) made the car substantially less valuable so I just took the liberties. I put in the overhead console, the leather bucket seats/Gran Coupe door panels, etc. and other upgrades such as the Elastometric rubber coated bumpers as I would have wanted if I had ordered the car. I am not heavily into E bodies like I am into C bodies so I decided to do this one differently.

The car was originally B5 blue as best I can discern and had a white vinyl top and bucket seat interior and bereft of any options. It was damn fast, but otherwise it rides badly, is noisy, handles not that well, bucket seats are not comfortable (has the 6 way manual ones too). Rather than use the word "restored" I should have said "made it like new".............

When most folks come to visit my place though, they tend to gravitate to that car as their favorite............especially the younger ones as like I was when I first acquired the car - as I said, it was a very long time ago now...............

I will ask my engine rebuilder about his experience with the 440 6 pack engines - he is the most acclaimed engine rebuilder in Southern California and his clients maintain as he does that none of his 440HP rebuilds has ever failed on the dragstrips or anywhere else and these are guys that have done well into the hundreds of passes at those strips. He refuses to hire any employees since he claims he can't fully trust them to make sure every bearing clearance is properly checked , etc. He has a wealth of original Mopar parts and prefers them to any reproductions except a very few others. He engine dynos every engine he rebuilds under load and even goes WOT during the break-in process and none has ever failed, and he guarantees they will not fail unless run out of oil or something really stupid. He also tells me if he gets ready to go to bed some nights and he recalls he left a tool he was using that day out of the proper place in his tool boxes, he has to go back to the shop and put it away before he can go to sleep. His shop is amazing. So that is the kind of guy I want doing my engines in the future.

I have had other racing engine rebuilders do some rebuilds and I have had some undesirable experiences so I just don't trust most shops anymore. This guy gets all my business for some time now.

 

[57fury440]

The problem with big block E bodies riding badly is too much weight on the front end. I have a 72 Barracuda with a 318 in it and it rides pretty good. I ordered it with the heavy duty suspension. With the stock quiet exhaust it is nice to drive. I think that's why the 340s were so popular, they were fast and drove well.

 

[CBODY67]

As to "Part Numbers", if the same casting item has some extra "labor operations" (as in shot peening or similar) performed to it after the casting comes out of the mold, for durability, then THAT requires a different part number for the same casting. Just as if they were sourced from a different source, that would be a different part number, too.

In looking in the '70 Plymouth FSM earlier today, it listed all 440 rods as the same weight. I also discovered the 426H rods were a bit longer than the 440 rods, too. More mysteries!

It's been a good while since I read about the special items in the 440 3x2bbl motors in the old Direct Connection Engine Manual, but it seems that whatever issues they had in 1969.5, those things were fixed in the 1970 motors? Mainly related to the new "low taper" lobe camshaft and stronger valve springs, as I recall. Plus a non-Edelbrock intake at some point in time.

Just some thoughts,
CBODY67

 

[57fury440]

I think the non-Edelbrock manifold is the cast iron version which weighs a ton. They most likely did that to save money.

 

[66 Monaco 500 365]

Now that I think about it, the only 70 up 440s I've been into is a 70 Superbird 6bbl and the 72 CHP car, both with the 6pack rods and damper, all the other 440s I've messed with are older.
Saforwardlook, that is a beautiful E!
Thanks for the clarification.

 

[saforwardlook]

The problem with big block E bodies riding badly is too much weight on the front end. I have a 72 Barracuda with a 318 in it and it rides pretty good. I ordered it with the heavy duty suspension. With the stock quiet exhaust it is nice to drive. I think that's why the 340s were so popular, they were fast and drove well.

The relatively heavy engine doesn't help but even with the 6 way adjustable seat, I still feel like I am sitting on the floor when driving it and because the seat cushion is so low, I also feel like I have to raise my head slightly and peer over the rim blow wheel. A friend of mine also had a 340- 6 pack TA and that car was much better balanced and the handling was pretty good

 

[LocuMob]

I still feel like I am sitting on the floor when driving it

Because you are! I noticed that in my friends '72 when my legs were basically flat with my feet on the pedals.

 

[polara71]

My 72 was probably the only car I had that I could stretch my legs out with an unbent knee. Still, it rode a step better than an A body.

 

[LocuMob]

Still, it rode a step better than an A body.

Can't wait to drive my Dart again. I forgot what it was like, but it was on gravel roads, with the tires spinning a lot and no brakes! Open headers too...

 

[66 Monaco 500 365]

Im confused....did you not read the responses to your original question?

There are no '6 pack rods' other than 1969.

I knew 70 and 71 6bbl engines came with big rods.
I had a 72 440 4bbl CHP motor that had big rods.
My question was did 440 4bbls in 70 and 71 have big rods.
and the answer is yes.