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Iroc-z86 06-23-2008 10:27 PM

question...
 
ok so this is a newb question that i never thought i would ask but i find myself wondering the answer to and couldnt really find an exact answer...

is it possible to make a stroker out of a motor that has some miles on it? ex. my 305 has 700 miles on it, could i at this time put a 400 crank into it without touching the pistons? ; more or less this is a general question, obviously this is stupid to do it with an engine that has a ton of miles of it because the block will be apart anyways.

thanks

Featherburner 06-23-2008 10:55 PM

You'd need new pistons.

LTb1ow 06-23-2008 11:06 PM

And how would you do it without removing the pistons anyway? Dumb response.

Pampered-Z 06-24-2008 07:37 AM

Quote:

Originally Posted by Shownomercy (Post 458485)
And how would you do it without removing the pistons anyway? Dumb response.

You don't need to remove the piston to replace a crank. Once you unbolt the mains and rods the crank will come out and the piston/rods stay in the cylinders.

To add to Featherburner's response:

There is actually allot of work that needs to be done to install a stroker crank, doing it to a high mile engine isn't that big a deal, just a few more things the machine shop would need to verify/do. (deck/line bore probably would be needed on an older block, a newer one may not need it?:

When you install a stroker crank, the larger diameter of the crank or "throw' of the crank will typically result in the stock piston skirts (bottom of the piston ) hitting the crank, or even pushing the pistons up into the valves. So you would need pistons designed for use with a stroker crank. The pistons would be shorter so they clear the crank, and the wrist pin would be relocated so at TDC the piston is not going up too far. Also depending on the size of the cam lobes you may need to replace or modify your connecting rods as they can make contact with the cam. The block itself needs to be machined/clearance to accept the larger diameter crank as well (so to do this, the pistons + rods would need to be removed.) A machine shop would remove material from the bottom of the cylinder walls and the sides of the block.

In addition, you can change the length of you connecting rods which will effect the time the piston stays at TDC. Now there are a few different ideas on this as far as which is better, but my point here is that if you change rod length, then you need piston designed for that as well. If you look at a catalog, you'll see pistons listed for CI and rod length.

All that said, unless you have a real need to run a 305 block or keep within a given displacement stroking a 305 is really not all that cost effective. I typical build would be .30 over and a 3.75 crank, this would yield a 334CI engine, so after spending the money you're still under the displacement of a stock block 350.

Iroc-z86 06-24-2008 09:22 AM

pampered-z, thank your for the response. I was just toying with the idea, i heard some people who have over 300 hp 305's and they did it rather cheaply; unfortunately the 350 block i have needs a complete over hall and i do not have the money for the machine work, thus i was asking about the new 305 i have. I am most likely going to put on the vette heads i have and a bigger cam in the fall when i put the tpi on. that is, unless i can find a mint shortblock 350 for cheap.

Featherburner 06-24-2008 09:31 AM

Quote:

Originally Posted by Pampered-Z (Post 458526)
You don't need to remove the piston to replace a crank. Once you unbolt the mains and rods the crank will come out and the piston/rods stay in the cylinders.

I've seen a crank swap with the motor still in the car. I don't recommend it but, I've seen it done.

Quote:

Originally Posted by Pampered-Z
To add to Featherburner's response:

There is actually allot of work that needs to be done to install a stroker crank, doing it to a high mile engine isn't that big a deal, just a few more things the machine shop would need to verify/do. (deck/line bore probably would be needed on an older block, a newer one may not need it?:

When you install a stroker crank, the larger diameter of the crank or "throw' of the crank will typically result in the stock piston skirts (bottom of the piston ) hitting the crank, or even pushing the pistons up into the valves. So you would need pistons designed for use with a stroker crank. The pistons would be shorter so they clear the crank, and the wrist pin would be relocated so at TDC the piston is not going up too far. Also depending on the size of the cam lobes you may need to replace or modify your connecting rods as they can make contact with the cam. The block itself needs to be machined/clearance to accept the larger diameter crank as well (so to do this, the pistons + rods would need to be removed.) A machine shop would remove material from the bottom of the cylinder walls and the sides of the block.

In addition, you can change the length of you connecting rods which will effect the time the piston stays at TDC. Now there are a few different ideas on this as far as which is better, but my point here is that if you change rod length, then you need piston designed for that as well. If you look at a catalog, you'll see pistons listed for CI and rod length.

All that said, unless you have a real need to run a 305 block or keep within a given displacement stroking a 305 is really not all that cost effective. I typical build would be .30 over and a 3.75 crank, this would yield a 334CI engine, so after spending the money you're still under the displacement of a stock block 350.

I was thinking all this but, it was late when I replied to his post. Thanks, John. :nod:
Iroc-z86, I'm not going to tell you what to do but, If I were you I'd take into consideration what Pampered-Z has said. You could have a fresh 350 with more cubes than a 305 stroker for less money.

Jersyboyy 06-24-2008 11:45 AM

Theirs a running 350 motor from a old pickup truck for like 500 bucks on craigslist 4 bolt mains too. I was thinking about picking that up tearing it apart sending to the machine shop and applying new performance parts and using that in the next 6 months maybe even stroking it -383. Would be a great way to build a decent powered motor for cheap.
Search North South & Central Jersey craigslist for 350's and parts, best place!

Iroc-z86 06-24-2008 11:10 PM

i have a 350 block with 4 bolt mains, it just needs machine work and my machine shop closed so i dont really know of any good ones around here and i really dont have the money to buy another motor :/

I know its not the best bang for the buck, i was more concerned with if it was possible to put a stoker crank with a stock setup without changing the pistons, and obviously its not recommended.

as for my 305, the most i am going to do with it is new heads, cam, and tpi and the rest of my funding is going to paint because my car needs it ever so badly, heck i might not even touch my motor til its painted but i dont know yet. thank you all for the help


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