Thats the only way I know how to check. I got mine from an '05 Malibu and it did not have forged crank.
edit: but I have read someone had an 05 Malibu with forged crank. If you really want the forged crank then check before you buy. The pulley came off real easy with my impact wrench.
[This message has been edited by LZeppelin513 (edited 01-06-2012).]
IP: Logged
04:32 PM
TheRealShadowX Member
Posts: 1456 From: Milwaukee Wisconsin USA Registered: Mar 2010
Originally posted by TheRealShadowX: Damn. I figure there must be some selection of cars that are known to have, or not have, the forged crank.
It's VERY important... I'm adding boost.
This information came about during a debate I had on another forum back in 06 after GM documented the 3900 in the Buick Rendezvous came with a steel crank and I mentioned the crank in my 3500 looked strange casting wise (lobular lobes) and I said I think I have a forged crank. To prove it I researched the the cranks and found that there was about a 5lb shipping weight difference between the crank part numbers with the one ending in 7484 being the heavier of the two. My funny looking crank had 7484 on the snout and that's how we determined how to tell them apart as well as figured out nearly every 3500 VVT or not, to 3900 had a steel crank. A picture of a cast crank confirmed it. Cast cranks have square edges on the bob weights, where the forged crank looks like something carved out of raw steel in those areas. The steel crank also has the classic wide parting line on the first throw as seen on forged small blck cranks.
Damn. I figure there must be some selection of cars that are known to have, or not have, the forged crank.
It's VERY important... I'm adding boost.
Not really, haven't read a thread yet where a boosted 60 deg motor broke a crank. I have a forged 3.43 stroked (offset ground) crank I need to sell since I had another ground to 3.555" if you're interested.
IP: Logged
05:40 PM
TheRealShadowX Member
Posts: 1456 From: Milwaukee Wisconsin USA Registered: Mar 2010
Not really, haven't read a thread yet where a boosted 60 deg motor broke a crank. I have a forged 3.43 stroked (offset ground) crank I need to sell since I had another ground to 3.555" if you're interested.
This is very true, BUT to my knowledge, none have pushed 20 psi yet..... Things are gonna break, but I hope the crank won't be one of them...
IP: Logged
05:47 PM
hookdonspeed Member
Posts: 7980 From: baltimore, md Registered: May 2008
my first motor was the steel crank, im pretty sure this one is cast i sold the steel on on 60degree for 150, as i didnt have time to swap them out before i had to put the engine in the car :/ i dont think i will have to worry bout this one breaking, i plan on eventually putting bout 12psi from a decently sized turbo for street fun on it.
Originally posted by TheRealShadowX: This is very true, BUT to my knowledge, none have pushed 20 psi yet..... Things are gonna break, but I hope the crank won't be one of them...
Boost pressure is just resistance to air flow, you can push 50 psi but if you don't produce the torque or the rpm/horsepower it's not going to happen so don't worry too much about it.
IP: Logged
06:15 PM
TheRealShadowX Member
Posts: 1456 From: Milwaukee Wisconsin USA Registered: Mar 2010
Boost pressure is just resistance to air flow, you can push 50 psi but if you don't produce the torque or the rpm/horsepower it's not going to happen so don't worry too much about it.
Again, true, but these motors seem to take very well to boost, so I'm sure it will make fantastic power.
The real point is the engine should cost about the same with or without the forged crank, so for the sake of peace of mind, I should hunt down the forged crank. No good reason not to.
This engine will see TONS of abuse. Just ask 86fierofun or gtxbullet.
Any leads on cars to check?
hookdonspeed, what car did your first engine come from?
IP: Logged
06:27 PM
TheRealShadowX Member
Posts: 1456 From: Milwaukee Wisconsin USA Registered: Mar 2010
How to tall if crank is cast: Look at flywheel mounting surface of the crank, where it is not machined (outside edge). If there is a small ridge, it is cast. If there is a small ground strip, it is forged.
IP: Logged
06:33 PM
hookdonspeed Member
Posts: 7980 From: baltimore, md Registered: May 2008
i wish i had taken a pic of my new engine... it *LOOKED* the same on the balancer side as the steel one did, but it was not the same # stamped. didnt know bout the flywheel side :/
there are 2 diffrences i noticed tho... the timinng cover had a plastic "shield" or plate on it from the engine w/ the steel crank, and the upper plenum dd *NOT* have a vac port next to where the booster hooks.
the cast crank didnt have the plastic plate, and *did* have the vac port....
the steel crank engine was from an 04 malibu... the cast was from an 05 malibu.
[This message has been edited by hookdonspeed (edited 01-06-2012).]
IP: Logged
08:58 PM
ericjon262 Member
Posts: 3131 From: everywhere. Registered: Jan 2010
i wish i had taken a pic of my new engine... it *LOOKED* the same on the balancer side as the steel one did, but it was not the same # stamped. didnt know bout the flywheel side :/
there are 2 diffrences i noticed tho... the timinng cover had a plastic "shield" or plate on it from the engine w/ the steel crank, and the upper plenum dd *NOT* have a vac port next to where the booster hooks.
the cast crank didnt have the plastic plate, and *did* have the vac port....
the steel crank engine was from an 04 malibu... the cast was from an 05 malibu.
it's only on the snout, my 06-g6 motor has a forged crank.
------------------ there's a Group on 60degreeV6.com for us 660 Fiero owners!
I just put a 0-mile 2004 Malibu in my 2002 Chevy Venture. I like it a lot better than the 3400. Quicker, quieter, and better mileage. Wouldn't mind finding another one to put in a FIero.
i wish i had taken a pic of my new engine... it *LOOKED* the same on the balancer side as the steel one did, but it was not the same # stamped. didnt know bout the flywheel side :/
there are 2 diffrences i noticed tho... the timinng cover had a plastic "shield" or plate on it from the engine w/ the steel crank, and the upper plenum dd *NOT* have a vac port next to where the booster hooks.
the cast crank didnt have the plastic plate, and *did* have the vac port....
the steel crank engine was from an 04 malibu... the cast was from an 05 malibu.
It's hit and miss, I purchased two motors each fitting the above description and both had the steel crank. Some steel cranks do not have the part number on the snout. There's probably a manufacturing plant association.
IP: Logged
02:48 AM
TheRealShadowX Member
Posts: 1456 From: Milwaukee Wisconsin USA Registered: Mar 2010
i sold the steel on on 60degree for 150, as i didnt have time to swap them out before i had to put the engine in the car :/ i dont think i will have to worry bout this one breaking, i plan on eventually putting bout 12psi from a decently sized turbo for street fun on it.
