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Discussion Starter #1
SO I just found out that the 2.5 MZR does infact have a forged crankshaft AND has Powder forged Connecting rods and lightened pistons! if anyone didn't know.

powder forging rods are quite stout. I don't know if the mazda speed 3 has the same type of forging, but I read online that powder forged rods are very strong!

so that is just another ++ towards my turbo build. lol. should be picking up the rest of the stuff to finish around the beginning of feb/ late january.

also got into an accident today well I wouldn't really call it an accident.. but i'm curious as to what decision you guys would do in the same situation.

I was sitting at a red light, truck pulls up behind me and he got closer then he realized I guess, he bumped my back bumper at probably less then 1mph, like a little push, my car moved probably like 3-5 inches ( my foot wasn't even on the brake lol,) We got out, inspected, pulled over to the nearest parking lot. We reinspected my car and his car ( which the thing that touched my car was his towing hook or w/e ) my car hadn't even a scratch, no damage under the bumper nothing. seriously not a scratch.

well I decided that it isn't worth even calling the police / calling my insurance about. and since he was a private in the army ( im in the army aswell ) and he looked scared to death like he killed someone, I just told him to please be more careful, he explained it is a new truck that is new to him blah blah..

well in the end he apologized and we left it at that and drove away.

would you guys do the same thing? or call the police / insurance ? I honestly didn't know what to do I have never been in such a minor minor accident with zero damage..
 

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I would have done the same as you. Since no damage was caused and no one got hurt obviously, there's no need for there to be a report and also no need to be on the car's record that it had gotten "damaged".
 

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Smells of Elderberries
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You should rephrase that ..."Some 2.5L MZR's possibly have forged crankshafts". :tongue: Unless they are using some sort of different type of forging process my crankshaft sure looks like a casting (Using Local speed shop, my old SHO, and pictures as reference). Lack of a defined wide parting line, color, texture..... just saying
 

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Discussion Starter #4
is your car a 2011? because so far I have only read that 2011 / 2012 have forged, and since I have a 2011 that is why i said it lol.
 

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Discussion Starter #5
but your car does have Powder forged rods. which ( after doing alot of reading about rods ) only have about a 12-18% less strength as forged steel, and i think I read it is like 2-3x stronger then cast , but c-70 steel rods are stronger then our powder forged

( and that 12-18% strength difference was from powder forging process over 10 years old, so i'm guessing they are even stronger now )
 

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is your car a 2011? because so far I have only read that 2011 / 2012 have forged, and since I have a 2011 that is why i said it lol.
Nice! I hope that is the case for all
 

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Smells of Elderberries
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I have a 2010... but since the first literature came out on the car they have stated that the 2.5L has a forged crank. I can only tell you what I saw when I had the oil pan off. From previous experience with other cars, what I've seen at speed shops for other cars and pics around the web it looks like a cast crank... but I am by no means a expert

This review is from December 7 2009 (2010 Mazda 3s Grand Touring Review & Test Drive | Automotive Addicts)

Mazda3s customers benefit from a healthier injection of Zoom-Zoom attributable to the new 2.5 liters of displacement. This new engine is similar in most details to that found in the all-new 2009 Mazda6i. Changes from the previous 2.3 liter I-4 unit include a fatter bore and a longer stroke packed into a cylinder block with unchanged external dimensions by using cylinder-bore liners made of a steel-molybdenum alloy offering strength and stiffness increases of 30%. A forged-steel crankshaft provides the necessary stamina. Twin balance shafts located in the oil sump cancel second-order noise and vibration, allowing this engine to sing up to its 6,200rpm redlines. The deep skirt block is engineered for extra stiffness and main-bearing caps are integral with a ladder-type lower-block reinforcement. To minimize the noise and vibration typically found on large displacement four-cylinder engines, the damper at the forward end of the crankshaft is equipped with two tuned masses. At the output end, a new flexible flywheel also curbs NVH
 

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Smells of Elderberries
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I think this has a lot to do with the discrepancy
This new engine is similar in most details to that found in the all-new 2009 Mazda6i
The Mazda parts list denotes two crankshafts for the 09+ Mazda 6i 2.5L by the 8th digit of the VIN one lists for over $1200 the other lists for just over $600. I just really think they never used the forged crank from the 6i on the 10+ 3's and the magazine articles and online reviews are just assuming it was carried over...IMO
 

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Discussion Starter #9
I think this has a lot to do with the discrepancy The Mazda parts list denotes two crankshafts for the 09+ Mazda 6i 2.5L by the 8th digit of the VIN one lists for over $1200 the other lists for just over $600. I just really think they never used the forged crank from the 6i on the 10+ 3's and the magazine articles and online reviews are just assuming it was carried over...IMO
hmm, well that could be the case, either way the non forged cranks have held 500whp+ without issues ( from what I read ) and also read a review that the 2011/2012 cx 7 with the 2.5 had a forged crank and 163bhp, which is weird why it is less.. but anyway

I found out that the rods we 2.5 guys have are Fracture split powder forged connecting rods, Which are tough, and another good thing is the Speed 3 rods are the Exact same! Fracture split powder forged and they aren't even thicker by any means! so I have a gooooood feeling that our 2.5's can put down 250-270whp without a hiccup. WE will see when my turbo build is finished.
 

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hmm, well that could be the case, either way the non forged cranks have held 500whp+ without issues ( from what I read ) and also read a review that the 2011/2012 cx 7 with the 2.5 had a forged crank and 163bhp, which is weird why it is less.. but anyway

I found out that the rods we 2.5 guys have are Fracture split powder forged connecting rods, Which are tough, and another good thing is the Speed 3 rods are the Exact same! Fracture split powder forged and they aren't even thicker by any means! so I have a gooooood feeling that our 2.5's can put down 250-270whp without a hiccup. WE will see when my turbo build is finished.
Only thing I keep hearing about our cars putting down that much power is the transmission can't hold up to it. But I haven't seen any proof on this so don't just take my word. Because if they can in fact put down that kind of power count me in.
 

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The less you have to involve the police in your life, the better off you are. I agree with your actions concerning the minor accident.
 
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