For those of you guys who have machined you smaller Vortech Pulley (2.87 and smaller)...how much did machine off the backside of the pulleys?

I'd like to get that done myself, but I'm hoping someone out there know the measurement so I can do it right...

<b>**EDIT: I meant jackshaft pulley, not cog pulley, in the title**</b>

 

the last picture in this post should help you out with regard to the 2.87 pulley:
https://my350z.com/forum/7382001-post66.html

the outside edge of the 2.87 pulley has a 45 degree chamfer on the backside facing the bracket. this is what rubs. basically, you need to machine down that chamfer so the edge returns at 90 degrees and no longer rubs. i've attached a quick sketch showing the pulley in section - the part highlighted in yellow needs to machined down.

i'm not sure what you have to do with a smaller pulley, but i'd imagine you'd have to machine down the edge further (if not completely).

 

Ahh...I get it...thanks

Looks like my pulley is going to need some more extensive work...its not a Vortech pulley so I really need to dig into it...

 

dang, are there a lot out there that come with this issue? i've read about it quite a bit.

I purchased a vortech 2.87 pulley from summit and i've never had an issue. I've had it apart a few times and no rub marks on pulley or bracket.

 

when i was doing the research / shopping for my kit i read that some pulleys are fine while others need to be machined. i had hoped i would get lucky, but the 2.87 pulley i got from summit rubbed when i bolted everything down
bolt everything down first to determine how much you need to mill down (if any). i think that's the only way you'll know for sure.

 

do you have pics of the wear marks on each surface? I've had mine off a few times (i was trying to decide between lower rev limit and 2.87 or higher rev limit and 3.12)

i didn't notice any wear at all on the jackshaft bearing part (on the bracket side) and none of my pulleys have any marks on them.

 

nah, no pictures. i tested fitted the 2.87 pulley shortly after I got it from summit, and, after a few turns of the pulley, i could see the backside was rubbing. i popped off the pulley and found that the jackshaft housing (whatever u call it) rubbed a perfect ring onto the pulley. i used that ring as a guide when i had the pulley machined down.

 

^ Did papa Dave fix it for you?

 

indeed he did

he also machined down my driver side cam cover so the belt doesn't rub. he did it so cleanly that no one even knows its modified