'349 vs. 360' Thought...

-
YoungBlood

YoungBlood

Jolt the Squares
Joined
Feb 9, 2007
Messages
450
Reaction score
18
Location
Western WA
Someone please feel free to shoot this down, or confirm or deny my pondering at anytime:

Would a 349ci stroker motor out perform a 360?

I was thinking that turning the mains down and dropping the 3.58" crank that I removed from the 360 into my 318, the reason why may be that it might make a superior motor than rebuilding the 360.

By stroking the 318 to a 349 might mean a 'best of both worlds' scenario, correct? (Torque + higher revving capability?)

It may not make the torque that a 360 would put out, but by using 360 heads with the correct valves, a port and polish job, and the correct decked piston, the 349's top-end would make the motor a decent screamer that put out more torque than an SBC 350 (349 would have 0.09" longer stroke, right?) and have a superior RPM range vs. the 360.

Am I going anywhere with this?
YB
 
Better off with the 360. The 349 is going to have unshrouding of the valves issues and its still 11 cubes smaller.
 
I see what you are trying to do but it is going to cost you some money in machine work to turn the crank down that much. Also those cranks have been know to have the oil holes move outward too much when turned down to 318 mains. Your thinking that a 318 will rev faster then a 360 is not really accurate. The only difference between your 318 and a 360 is bore size. One last thing you have to worry about is finding a piston. With the increased stroke your going to push the piston up half the amount of increased stroke(.135). You may get lucky and find a piston with a lower compression height but don't bank on it. All in it can be done and it's a good idea.
 
You can buy a 3.58" stroke crank that all ready had the 318/340 main size.
 
If you build a 349 it is basically a de-bored 360 with smaller mains and a lighter stock piston. The advantage of these two items will be cancelled out by the lose of cubic inches. With all things being equal; compression, camshaft, intake, carb, headers I don't see the 349 out performing the 360.


Chuck
 
If you want some real good results,stroke the 360..why anyone would stroke a 318 when it cost the same if not less to do it to a 360,even better find a 340 block..:-D
 
AdamR said:
Better off with the 360. The 349 is going to have unshrouding of the valves issues and its still 11 cubes smaller.
Click to expand...

Unshrouding of the valves? Wouldn't that mean that I could just have a larger cylinder bore to match up to it?
 
Depends on the valve size and whether or not you can bore the block out enough.
 
You're really not getting anything out of it. The only thing that affects rev-ability (as far as the bottom end goes) is strength and stroke. Bore has nothing to do with it. So essentially, they will both rev the same but the 360 will make more power because of the bigger bore.
 
My confusion was the thought that a 318 could out-rev a 360 because of the shorter stroke. I figured even though you would have the same stroke with a 349, it would rev higher and easier with lighter pistons. But because of unshrouding of the valves and having to bore the cylinder wall, it wouldn't make much difference.

Keeping the 360. Thanks guys.
 
You must log in or register to reply here.
-

Back
Top