Holley accessory drive 20-137 LS3

[DT69Cam]

I was reading the instructions for my Holley accessory drive set-up on my crate LS3 engine and it states trimming may be necessary on the water pump bosses as well as another area. The LS engines use a type 3 water pump as per Holley. Any of you guys have to trim your water pump???

[rocketrod]

I don't remember having to trim mine. I wouldn't worry about it. Just mock it up and trim if needed .

[DT69Cam]

I don't remember having to trim mine. I wouldn't worry about it. Just mock it up and trim if needed .

OK, thx.

[badazz81z28]

I'm using the C6 pump from an 08 and no trimming.

[DT69Cam]

I'm using the C6 pump from an 08 and no trimming.

Thanks.

[12sec ss]

I run lsa pump on one car and gen5 camaro pump on other, nothing to trim

[CapSS92]

I used stock C6 accessory mounts with the Holley AC Sanden mounts and I did have to grind on the water pump bosses. The LS3 was from a 2008 Corvette. There was some interference on the lower bolt for the Holley AC bracket when it came time to install it. I ground down quite a bit and was still having issues so I did the second option that Holley recommended and removed the water pump to install it and it went off without a hitch. I should have done that in the first place.
I also had to grind down a couple of place on the water pump so the belt wouldn't rub on it. I t was close and might have cleared but it was easy to grind them down a little. The locations are listed in the instructions and I just followed that. Hope this helps.

Alex