Holley 20-134 and 21-3

[Justin71105]

Installed the Holley high mount ac bracket yesterday. Everything fit really well and is worlds above the kwik performance setup I have been running.

Only issue I am having is getting a belt that tensions properly.

Measured the belt routing with some 12 ga wire, paracord and finally ran tape around everything. Got right around 114.5 for all three measurements.

So I went by the paperwork and came out with 2908.3mm and subtracted for un-sprung tension-er (28mm).

Came out to 2880.3, closest belt I could find is the Gate K061130 which is 2886mm.

Well that belt was so tight I couldn't get it over the water pump with tension-er fully down, I returned it and picked up the size up K061140.

This K061140 belt is a little loose and there is no in between. It's slipping at high rpm, voltage drops under hard acceleration.

So I called Holley this morning and they said they had never had this issue with a belt not fitting. He said to try the 61130 again and turn motor while belt is against water pump to pull it on.

Worried this is going to be too tight and chirp my pulleys or just sling the belt off.


Has anyone used this kit and have a suggestion?

I will try the belt again and if it is too tight, thinking of replacing the 90mm drivers side idler with a 80mm or 76mm to slack it up a little.

I will say other than the belt tension issue I am very happy with this setup, it looks factory and the belt no longer pops up over compressor pulley with ac on.

Just need to get the belt to have proper tension with either idler size or hopefully the K061130 will roll on and have enough give to not cause issue.

https://imgur.com/a/CDoWiFC

[Justin71105]

Okay here is the final outcome for me, I finally found a way to get the K061130 to fit.

This is for all stock truck accessories, Holley 20-134, 21-3, Dayco 89059 idler, Gates 38194 tensioner all recommended by Holley.

The kicker is I have a 145a alternator which makes the K061130 not want to go over water pump or tensioner no matter what I did.

Got another belt today and Dorman 419-610 idler Pulley (76mm).

With the new idler pulley installed in place of the stock 90mm the belt is still very tight to get on but it lines up with the tensioner marks in the product install manual almost perfectly now.

So if you are having issues with finding a belt for this kit, and have a 145a alternator like me. Swap out your 90mm idler puller under alternator for a 76mm and a K061130 belt will fit.

https://imgur.com/i00zLFc