100mm Tensioner Pulley Upgrade

One Bad Sixxx

Twin Precision 4.3L V6
I did this long time ago, and posted the How-To on V6P. So here it is here, for those needing extra wrap, and lessen your chance of belt slippage when running a blower. So I went out and got it done, took pics with part numbers, for the case if anyone else is gonna wanna get this done. So, this morning started and went to Napa after class and told the guy what was up, and he right off the bat knew what to go for.

Heres the 100mm Tensioner Pulley [PN: 38002) still in the box...

I gave him the part number [6203] to the bearing and...

Compared the extra bearing to the bearing that was already in the pulley and it was a perfect match. Pics with them both out of the box...


Youll see some space in there, where youll be able to snuggle in the extra bearing...

Took a socket, and a small hammer and gently tapped it in. Youll know once its gotten to the point where it wont go in any farther. Youll see that it looks like theres still "space" but its really just the way the outer edges are curved on the bearings, though theyre indeed touching.

I didnt bash it in too much, to the point where I started to push the other bearing out of place, so its still pretty flush...

And voila. Heres the outcome...



I'm running the Reichard Racing 3.2" billet pulley in my set-up, which is why I did this tensioner pulley enlargement.

Here's a picture without a belt.

Here's one with the belt installed without tension.

Here's with everything installed, tension on the belt.


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Active Member
Sorry to resurect something so old. I assume the install process is the same as installing a new normal sized tensioner pulley? And that the bolt used remains the same?