Never seen all 8 before. And they came out of a 383 that was factory .020 overbore.
Copper Clad Connecting Rods
- Thread starter Dana
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Demonic
Well-Known Member
Those pop up sometimes. Other members have had motors with 8 copper clad rods. I believe they are trying to decrease side clearance between the rods?
Mopar44134
Well-Known Member
Never heard of Copper Clad before...interesting
THere's a few posts about them. Search Results for Query: copper connecting rods | For A Bodies Only Mopar Forum
Have a 400 at the shop now that is also factory 020 over. It has 4 copper rods. Just a FYI, the factory 020 "440" is not 020 over, it is actually .022 over, which would be a bore of 4.342. Bore size look familiar? Yup, a standard 400 size. Anyway a few copper filled rods for comparison.
I’m guessing a 400 piston and rings with a taller compression height? I had a 1972 400 hp short block once that the pistons were just barely below deck, about.015 or so, so I’m thinking it was probably the same piston. I apologize for the de-rail, but folks I’ve talked to who have owned 400 HP that did the old school performance mods (TM6, headers, Crane Blazer 288/.480 cam, distributor recurve) claim it was more like a 340 than a big block. A whole of fun in a ‘72 charger with an automatic and 3.91 gears.
I see Cleveland stuff. lol
I’ve put the .020 over 440 piston into a 400. It’s approximately.100 thou taller piston so it gives the 400 approximately 2 more compression points. Kim
pishta
I know I'm right....
Copper builds up the flawed rod id so it can be machined again to a std bearing insert OD or side clearance. It's just a cheap attempt to save a flawed rod. Works.
40 over 440 pistons getting stuffed in a 400 today, which is 18 over for the 400. Here's the 4 copper filled rods. Bobweight at 2694 grams JUST makes it for an internal balance.
I would not use them.
I’m all ears
I have used those rods b4 with no problems. Kim
I’m not being a smartass or looking to argue. Just want to do what’s best. I’m all ears. Building a 383 about 500Hp, A body, stick shift. Thanks
Which 440 pistons will work in the 400? What compression height?
Low compression pistons. They were in a 67 440 that we’re about .080 in the hole. Kim
Copper is soft. It was a bandaid to save a nonconforming part. Big end of a rod? add weight? What happens when the copper peels off? Where does it go? With everybody pitching stock rods, someone should have a good set you could get. I'll go through my stash of parts. I know I have extra RB rod sets but I have to check on 383 rods.
I have not gotten the pins pressed out yet. There is no copper visible in any of the big end saddles. But the rods were only machined on the side that rides against the other rod. I’m beginning to think that these particular rods were clad in order make up side clearance.
Could be or they've been rebuilt before
1.928 ch I think is the cast piston in the low compression 440
If I remember correctly, that would put the piston around -.005 - -.010 deck
CNC-Dude
Well-Known Member
Yes, I've seen it in Chevy and Ford rods as well. Sometimes just on the small end and sometimes the big end, then the whole rod at times. According to some GM engineers I've spoken with, it was to keep from scraping rods that were bored too big on the B/E or S/E and otherwise being non conformance per the specs as 66fs mentioned. Just like the Maltese Cross stamp on many Mopar blocks denoting an odd oversize bore or rod journal size. Any attempt to keep the production moving forward.
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