MMR forged connecting rods

Svtcobra916

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I am currently in the process of rebuilding my motor and I'm trying to make a decision on which connecting rods to use. I came across these MMR rods that are $100 cheaper then modmax and $200 cheaper then Manley. So I guess I'm just trying to get information from anyone who's actually running these in their car and how they're holding up.

 

mlackke

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I did order internals from MMR long time ago, but i got quickly very suspious about connecting rods since they looked chinese made.

I did sent send one of the rods to my friend who had access for machinery for xray (it told how much each material it had % wise) and conducted strength test (hardness)

Result? Xray etc test showed it was far away filling 4340 criteria and strenght of the steel was weaker than basic nail from local wallmart.

I throwed those rods to trash and order manleys...(they were real 4340 steel).
 

robvas

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Svtcobra916

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Appreciate the heads up, everyone. I'm rebuilding a 97 cobra, and originally purchased the MMR connecting rods, but after this thread, I called and swapped to Manley.
Tbh with Im going with the MMR connecting rods and diamond pistons. I'm going with MMR because I seen someone's Instagram of them running the MMR connecting rods with twin turbos pushing over 1000hp. They had they're whole build documented so I feel I can trust those rods to handle the 500 hp I'm shooting for.
 

Blkkbgt

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I did order internals from MMR long time ago, but i got quickly very suspious about connecting rods since they looked chinese made.

I did sent send one of the rods to my friend who had access for machinery for xray (it told how much each material it had % wise) and conducted strength test (hardness)

Result? Xray etc test showed it was far away filling 4340 criteria and strenght of the steel was weaker than basic nail from local wallmart.

I throwed those rods to trash and order manleys...(they were real 4340 steel).
After reading that I'd use coyote rods before MMR. I know the coyote rods aren't exactly weak but I always thought MMR was at least a step up.
 

CourteousCain

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Tbh with Im going with the MMR connecting rods and diamond pistons. I'm going with MMR because I seen someone's Instagram of them running the MMR connecting rods with twin turbos pushing over 1000hp. They had they're whole build documented so I feel I can trust those rods to handle the 500 hp I'm shooting for.

Honestly, I'm not planning on going with any forced induction, so I won't be even at 500hp likely.
Hopefully they're quality and they do last, I just could not find enough on them to feel 100% confident. For me, it's worth the extra money to go with the Manley rods, but for what I'm doing the MMR rods would likely have worked as well. Hell, even the sinter forged ModMax I beam rods would have likely worked for me.
 

mlackke

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I did order internals from MMR long time ago, but i got quickly very suspious about connecting rods since they looked chinese made.

I did sent send one of the rods to my friend who had access for machinery for xray (it told how much each material it had % wise) and conducted strength test (hardness)

Result? Xray etc test showed it was far away filling 4340 criteria and strenght of the steel was weaker than basic nail from local wallmart.

I throwed those rods to trash and order manleys...(they were real 4340 steel).
Just checked for fun and it seems MMR doesn't sell those rods anymore, atleast for 4.6 anyways, only Manleys.

Also OP link to MMR is dead.
 

CourteousCain

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Just checked for fun and it seems MMR doesn't sell those rods anymore, atleast for 4.6 anyways, only Manleys.

Also OP link to MMR is dead.
Oh that's interesting... no wonder they did a free upgrade to the Manley rods. I'd called about swapping to the Manley rods and was told that the 4.6 MMR rods were on "indefinite backorder." Wonder if they're permanently discontinued.
 

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