Took a gambling trip to Louisiana, on the way there I set the cruse control to 95 MPH.
The engine sat dead on at 3K RPM, and in the vacuum at 10 PSI.

So the question is If I install a lower 6 LBS (no chip) The truck is mostly stock, with the same conditions cruse set at 95 MPH, what will the boost Gauge say?? 4 PSI in the vacuum??
I also had the best MPG of 14.75 that is a new record! Will this Pulley also change MPG??

Oh, I lost on the gambling!!!!!

 

Cruising to work today at 95 mph was a steady 10in of vacuum. (Needless to say, I was running late)

 

Thanks for the info MaxPower!!

Now I’m really confused, if the engine is turning 3K RPM (Stock) and the SC is turning 9K (I don’t know, I have seen a spreadsheet on the SC speeds)!
Now replace the bottom pulley say with a 6-pounder, engine running at the same speed 3K the SC must be spinning at a much higher rate say 13K (once more I don’t know the true rpm).

So why is the Vacuum still at 10PSI???????? Is the SC dumping the extra charge?? What is the deal here, Somebody please!!!!

 

I'll double-check on the way home

It *may* have been at 80-85mph, now that I think about it, but I was up over 100mph this morning on the way in ..and it sure was around 10in of Hg at cruise (again, possibly at 80/85mph).

Remember, the S/C may be spinning faster, but the bypass opens up on vacuum, dropping boost when it's not needed.