How do I know if I am running the stock pulley on my newly aquired lightning? It is about 3 and 1/4" in dia....also, what should the boost go to in stock form? It pins the 10 on my factory gauge...is that normal for stock?

 

^^^ second guessing now...is it the pulley at the eaton that gets swapped, or down at the crank??

 

You can change either one. The stock pulley on the supercharger will measure 2.93" where the belt rides. If the lower has been changed you can usally tell because most of them do away with the factory cage supporting the lower pulley.

 

Are there pros and cons to witch pulley you replace? Or just personal preference? Why do some people appear to have both...are they just stacking them up for more boost? I also see plenty of idler pulleys for sale, saying that the factory "heavy" ones are costing me power....how true is that?...I wouldnt think an idler would have much of an effect. Thanks for the newbie help.

 

The lowers are easier to change out. I run both because I already had a lower and it was cheaper to buy a new upper than lower. Mostly it's just personal preference.

As far as idlers go. The stock ones aren't heavy, so I don't know why they're saying that. The main thing people upgrade the idlers for is more belt wrap on the blower, as we're prone to some belt slip even in stock form.

And the stock boost guage is pretty much worthless. You will see 10 psi in cold weather. Do NOT beat on it in this cold weather unless you want a window in the side of your block. The blower loves this cold air, but the rods do not.

Check out this link for the local MO/KS L club..... MKLO

 

Thanks....good tip on the beating on it...

 

Swaping the upper pulley will only net you around 2 more lbs of boost. The lowers you can buy in 4,6, and 8lb sizes.

 

Doing only the lower leaves the same amount of belt wrap on the upper so you don't have as much slip. I had a Metco 6 lb on my lower but you could change it out for other ranges also pretty easy because you use a hub to put the new pulley on.

I would say your truck has something changed if it pegs the stock boost gauge. If I remember correctly, mine would get close to 10 or maybe even hit 10, but it wouldn't peg it in stock form. But then with the 6 lb pulley it would definitely peg the gauge.

I did the CAI at the same time. If you have that done it might just be the reason to gain the extra couple pounds of boost.

They are a fun truck with some good potential....brings a tear to my eye talking about it in the past tense.

Dan

 

Even with the stock filter, I'd see 10psi on occasion depending on temps. Considering it's been 20 and below for the last couple days around here.....

 

Yea. It was the temps I am sure. Today at around 60* it throws up about 8. Trying to decide if I should go with a 4 or 6 lower pulley. I will obviosly tune for either one, but I want to be on teh safe side of things. Is a 6 starting to push it with just a tune and CAI?