Belt size for torque converter

[2SlickNick]

I made a custom jackshaft with a distance of 8.5" from center driven to center driver. 20 series with a 7" driven.

It looks like the only belt that will be available is the 203583A with distances of 8-5/16 -- 8-3/8 Little tight but if I go to 203584A looks like a little too loose
What do you think??
Go with the too tight or a little too loose?

 

[landuse]

If it is loose you could always shim the engine up

 

[KartFab]

Too tight u break stuff, too loose you don't.

 

[2SlickNick]

Thanks for the replies.
I am not sure where I would shim.
So it looks like I will order the slightly bigger one. Thanks.

 

[2SlickNick]

Oh wait I get it now. If I shim engine with a set if washers it raises it a hair to increase my center to center distance. Thanks

 

[landuse]

Oh wait I get it now. If I shim engine with a set if washers it raises it a hair to increase my center to center distance. Thanks

Correct