Which years are the 2p rear main cranks compatible 305&350?
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Joined: Jul 2001
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From: Pueblo Co
Car: 1989 C4
Engine: L98
Transmission: 700r4
Axle/Gears: 307
Which years are the 2p rear main cranks compatible 305&350?
Title takes care of the major question, but if you do use a compatible 350 crank in a 305 which ballancer should you use? If the cranks are the same whats the reason for two different size ballancers?
The stinking LG4 (82) that I stuffed in the truck is droping oil pressure alot when warm now and with my luck its going to need a crank
SSC
The stinking LG4 (82) that I stuffed in the truck is droping oil pressure alot when warm now and with my luck its going to need a crank
SSC
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Joined: Jul 1999
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From: Loveland, OH, US
Car: 4
Engine: 6
Transmission: 5
The cranks are the same dimensions, even the same casting in most engines (442), but are sometimes balanced slightly differently depending on what pistons were used. Much of the time that's not even different. Bottom line, there's really no such thing as a "305" or "350" crank beyond what a balancing shop can deal with, which is something you should always do anyway whenever you are putting a whole short block together.
The balancers will interchange as far as the crank is concerned. The 350 ones are usually larger and do more damping of harmonics, since the 305 is usually used in lower-stress applications. However, the timing marks are different on different engines, and in different places sometimes; one of the bigger 350 balancers will hit the timing mark on a 305, which is where it is so that you can see it (?) behind all the accessories; so if you use the bigger balancer, you can pretty much kiss the timing mark good-bye. Not that it makes a whole lot of difference anyway.
I'd recommend using the balancer that came with your motor no matter what crank you use, as long as it's not a 400 one.
The balancers will interchange as far as the crank is concerned. The 350 ones are usually larger and do more damping of harmonics, since the 305 is usually used in lower-stress applications. However, the timing marks are different on different engines, and in different places sometimes; one of the bigger 350 balancers will hit the timing mark on a 305, which is where it is so that you can see it (?) behind all the accessories; so if you use the bigger balancer, you can pretty much kiss the timing mark good-bye. Not that it makes a whole lot of difference anyway.
I'd recommend using the balancer that came with your motor no matter what crank you use, as long as it's not a 400 one.
Joined: Mar 2000
Posts: 43,187
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
You can get 305 pistons that are weighted to balance properly with a 350 crank.
I'm sure that there are a lot more than two different balancers out there. I found out that the '86 LG4 balancer (and timing tab location) was different than the '87 LB9 I had, even though the accessories were identical between the two.
A little curious why you'd have a 350 crank but not the block. Why not use one of those "plentiful" 327's down there in Pueblo while you're at it?
I'm sure that there are a lot more than two different balancers out there. I found out that the '86 LG4 balancer (and timing tab location) was different than the '87 LB9 I had, even though the accessories were identical between the two.
A little curious why you'd have a 350 crank but not the block. Why not use one of those "plentiful" 327's down there in Pueblo while you're at it?
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