schmendog

iTrader: (10)

Im shopping for all my mandrel bends from Columbia river, and notice there are options for 4" or 6" radius on the 180 degree bends. What's the better option here?

Is the 4" just a tighter bend?

oscs

iTrader: (19)

Yes the smaller CLR the better "center line radius"

stevieturbo

Smaller may be easier for fabrication in tight spaces.

But as far as flow is concerned, I dont think you'd ever say a tighter radius would flow better

schmendog

iTrader: (10)

OK thanks guys. Ill go with the 4" then... not a whole lot of room in the GTO engine bay.

oscs

iTrader: (19)

I wouldn't be worried at all about flow characteristics between a 4-6" CLR pipe. Reality is the room you have is what you have. The 4" will allow you to maximize your available space better than a 6"

Good luck OP and post pictures