Alternator pulley size - serpentine

[SMB]

Guys, I'm after some validation please on what should be right.

I have both a serpentine chimaera and Griffith. I have a small belt squeak on start up from the Griffith so investigated further.

The tensioner and belt sit closer to the exhaust on the griff, having looked and compared to the chimaera, the alternator pulley on the griff is much smaller, 5.5cm diameter vs 7cm. Not loads but it pulls the tensioner 2cm away from the exhaust. Also I think this means the tensioner may not be fully tensioning the belt causing the slip . Otherwise the other pulleys and belt length are the same.

The alternator is a Land Rover badged one but I'm wondering it they fitted the wrong pulley at some point in the past.

Could someone please measure the diameter of their alternator pulley (external) and confirm.

I see race tech do a 66mm(assume that's 66 in the grooves, and 70 external)

Thanks

[Colin RedGriff]

Maybe easier to get a slightly shorter belt, they come in various lengths

[SMB]

Colin RedGriff said:

Maybe easier to get a slightly shorter belt, they come in various lengths

That would be one potential solution but I'm also concerned that as its in nearly 30% smaller its spinning 30% faster and may be over the design limit for the alternator bearings at high engine revs, or at least premature failure.

Edited by SMB on Monday 30th May 17:55

[SMB]

Colin RedGriff said:

Maybe easier to get a slightly shorter belt, they come in various lengths

That would be one potential solution but I'm also concerned that as its in nearly 30% smaller its spinning 30% faster and may be over the design limit for the alternator bearings at high engine revs, or at least premature failure.

Edited by SMB on Monday 30th May 17:57

[Colin RedGriff]

My pulley is 52mm where the belt sits