All this time I thought I had a 6:1 disc in there and ended up buying the recalibration kit from Vortech for $50 for the whole kit of discs.

Opened it up and measured the disc and it was 2.22" so that is an 8:1. Everyone kept telling me the stock FMU comes with a 6:1.

MardisGrasMax told me that if I plan on running the 3.125 pulley I definetely need to be on the 8:1 disc.

Am I correct? or Do I need the recalibration disc kit anyways? Now when I measure the disc, we talking about the disc itself right? Not that ring or anything.

And I hate how vortech aint got no directions on how to install them, does that ring go what way? I noticed a cut on the ring and assumed it goes facing down and not towards the rubber gasket. Does that cut need to point at a certain hour?

Damn.....

Yes I bought the s/c used, but he had a stock pulley on it and wondering why would he need to put an 8:1 disc on it if he running stock pulley? I know he never changed the pulley.

Dixit

 

Stillen is wacky... If you have the 8:1 and you have verified it, just put it back the way you found it... no harm no foul.

 

Words from the Wise one has spoken........

 

Now you have me worried as to which disc I've got in! I put in the 3.33" a few weeks ago and I think I'm running lean (that silly a/f gauge will have to go for an EGT gauge). I yanked out two plugs this weekend - one from the front and one from the back - and they look as good as new.. uh oh.. it's been over 10k on those... I'm thinking either I forgot to turn off TCS too many times or I've got a lean condition.. and after my not-so-moderate recent driving, I better be careful

BTW : What diameter corresponds to each ratio?

 

4:1 = 1.59"
6:1 = 1.85"
8:1 = 2.22"
10:1 = 2.47"

 

Sweet Thx!

 

I also got the 8:1 with my s/c kit.....

 

I measured my FMU and it's 3.3". Is it the 12:1 disk?