i can get a fully forged bottom end for cheap...my buddy bought it and decided to go another route....and hes gonna off it to me...

my questions are...is the crank and rods the same for 305/350's...cuz i was gonna put a 350 in my ride but if these parts are the same then im gonna run the **** outta my 305 for a while...see what it can do....then put the 350 in with the forged parts..
let me know guys

 

Yes, they are different.

 

the stroke is the same on the 305/350 right?....why wouldnt it work?

thanks for the reply super

 

I thought the only difference was piston diameter.

 

It would take much more than piston diameter to get another 45 cubes out of an engine. The stroke is different....

 

the stroke is the same....... it's the bore diameter thats different.....

here's the formula..... bore x bore x stroke x number of cylinders x .7856

the bore of the 305 is 3.74..... if it was 4in then it would be a 350 with a 3.48 stroke crank......

 

Sooooooo
The only diff is piston diameter?

 

thats what i was thinking....the stroke was the same (crank, rods) but the bore was smaller on a 305....i can see that this is gonna be a good thread

 

The difference between a 305 and 350 crank is in the balance. The two cranks are way different in the balancing and this will really cause a shaky motor that will not last. I know this applies to the old 2 piece blocks but I am not sure about the 1 piece seals but I would imagine that they are the same. You could probably have a machine shop rebalance the crank but I am not sure if it would take heavy metal such as mallory to accomplish this. As a thought you may be able to sandwich a 400 balance wieght fot internal balanced flywheel on a 350 crank into a 305 rotating assembly to make it work. O well just food for thought.

 

thats what i found strange!!!!!

if you went to a gm dealership and purchased a 87 up 1 peice seal 305 crank the part no is the exact same as the 350!!!!!

weird huh???? but like old dude said above, it will need major machine work!!!

it's kinda like a 400 crank...... if you put it in a 350 you get a 383....

if it goes in a 305 you get a 335!!!!

to me a 305, can be made to put out hp, but the dag on bore really limits hp....

when will gm smarten up and bring back the 302?????

 

the reason behind the thread is because i gettin a forged bottom end for my 305...and im gonna run the snot of it...then im gonna put a 350 in it with the forged parts....theres a machiene shop right by my house so how much would it take for them to rebalance it for a 350....
thanks guys

 

Why not find a good block out of a latemodel truck?? Trucks tend to have the high nickel blocks that dont wear as bad and usually can be reringed without boring. Usually you can pick up a block at a pick apart or in the paper real cheap, or you coulf find an old dime a dozen 2 piece rear main and install the 1 piece adapter into the block that i have seen several times from places like jegs or summit. I used to find old 350 blocks from $50 to $150 apiece. Just my thought. For the price of a block would equal the price of the balancing for a $305. This would give you a couple of free cubes. This is just the way that i would do it.

 

the reason im goin 305 is cuz i already have the forged bottom end...and block i will go 350 eventually but right now i dont have the cash to buy a block and rotating assembly...that why i asked if i can use the 305 crank and rods when i build a 350

 

Balance and bore dia. are the differences. If i'm not mistaken the 1 piece cranks are the same however the pistons are quite different. From what i know GM uses the pistons(ex. heavier for the 305) to make up for rebalancing the cranks. When you spend hundreds of millions of dollars engineering goes a long way.......

 

One the 1 peice they are the same (crank and rods). Pistons are different.

 

so i can reuse the forged parts for the 350 when i build it....i just have to get the 4 inch pistons....i looked in the parts catalog i have and the forged piston for a 350 are 259.....

thanks alot guys!!

 

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