Belt size for Singer alternator (2010 Toyota Corolla)

[SPLainin to do]

Hoping this is the right area for this.. 

I am going to be upgrading my alternator (2010 Toyota Corolla, 1.8L) from OEM to a Singer 240Amp. 
The OEM Pulley is 2.43"
The Singer Pulley is 1.7"
My question is, what belt size do I use to replace the OEM? 
OEM is 48" Serpentine.

Thanks in advance if anyone knows the answer.

[audiofanaticz]

Typically a half inch to 1 inch smaller than oem belt length to make up for the smaller diameter pulley.

 

[audiofanaticz]

The belt tensioner usually has a bit of play in it both ways.

If you want to be sure remove your current belt and take a smaller diameter rope (1/8inch or so, something that is about the same diameter of your belts height).

Once the new alternator is installed and wrap the rope around the pulleys in the normal belt routing being sure to put as much tension on the belt tensioner as possible, and then mark the rope where it comes back around and meets the starting point.

Once done measure that length and try to get the belt length as close to that size as possible without going shorter.

[WalledSonic]

2 hours ago, SPLainin to do said:

Hoping this is the right area for this.. 

I am going to be upgrading my alternator (2010 Toyota Corolla, 1.8L) from OEM to a Singer 240Amp. 
The OEM Pulley is 2.43"
The Singer Pulley is 1.7"
My question is, what belt size do I use to replace the OEM? 
OEM is 48" Serpentine.

Thanks in advance if anyone knows the answer.

Assuming belt wrap is 50% of the pulley circumference...

(pi)x(D/2)=linear distance/circumference around half the pulley.  

OEM=(pi)x(2.43/2)=3.8"

Singer=(pi)x(1.7/2)=2.7"

3.8-2.7=1.1"

As AF said above, about 1" smaller. 

[SPLainin to do]

An update for any future browsers looking for an answer..

I bought three belts downsized by 0.25 inches from OEM starting at 47.5". The 1st belt I tried worked.
OEM is 48 inches.. The belt that works after installing the Singer alt, is measured @ 47.5 inches. The other 2 that weren't used were 47.25 inches, and 47 inches. 
All other pulleys are stock OEM size. Only the alternator had a different than OEM pulley size.

3 belts of your choosing that will work are:
Part# Bando 6PK1205
Part# Dayco 5060475
Part# Goodyear Continental Elite 4060475 Poly-V (Gatorback design)
Some others are out there..




Tags for search: 2009 2010 2012 2013 Toyota Corolla 1.8 2ZR-FE, Singer High output alternator, serpentine belt

[WalledSonic]

Good feedback. However, all three should have fit with varying tension on the belt tensioner. If the dimensions you gave were correct, then you should be using the 47" version if you want tension as close to stock as possible.  Then again, you may never have any issue. If you do, belt tension should be the first thing you'll check. Also curious, did you actually install all 3, or just stop when the 47.5 fit?

[SPLainin to do]

Starting at the second shortest to OEM, I only installed the 47.5 and kept with it because it worked so well during testing. It tensioned out just like OEM, and didn't seem to present any issue. So I figured, why mess with success. I'm going to test it out some more today, and watch for any problems, but so far all is well. I will update if I run into any issue! 

Oh, to add, there would likely be enough tension room for the other 2 belts as well.
It isn't an auto tensioner like on the 2.4, but a bolt/bracket tensioner located on top of the alt itself.
There looks to be enough adjustment play to possibly accommodate so it's good to know the range of options. 

[WalledSonic]

Nailed it. Nice