I tried to search it but couldnt find a clear answer. I have a 2003 HD truck and want to put a Lightning pulley on it. Just wanted to know how much boost I will be running. Thanks

 

I thought it was ~8psi on the factory gauge.

 

Harley have 6PSI which is why there not the 380hp there what 340 or 360??

Lightning has 8PSI stock, but if you put a K&N Panel in you could boost closer to 9PSI, at the track i have a K&N panel and a bunch of holes cut in the bottom of the air box, and i decided to take out the filter for a few runs, and i was boosting close to 10.5!!

 

If an air filter actually gave even a 1 PSI improvement, it would make more HP. Air filters do not make more HP on a stock engine. Ergo, any increases in measured boost with any air filter must be measurement anomalies, not real increases in boost.

 

HE said "ergo" He heh

 

I had 8 psi stock. With the addition of the Accufab single blade throttle body and a different filter (Pro-M 92mm MAS or stock MAS + JLP CAI), I'm up to a little over 10psi.

Paul

 

mine was always 9 on my guage if it is right. It goes there everytime i pin the throttle to the same spot at 9.

Vinny

 

Our stock gauges are not reliable for accuracy.....

 

yeah i didnt think they were but if it is correct i wont be complainin to ford about my extra pound. No mine is probably just off. At the risk of sounding stupid, If you install an autometer boost gauge they are correct so why are out stock gauges not. .They connect to the same spots right. is the needle just not accurate or is it getting some kind of wrong reading. Just curious. I dont really know how the boost gauge works.

Vinny

 

My stock guage has been close enough to tell increases. How accurate is mine above 8 PSI, I don't know. Mine read dead on 8 PSI bone stock. If you mod the airbox with a K&N you will definitely see an increase in boost.

Click on the link and scroll down to see the results I got with the stock pulley. The only other mods were a 160 stat, sparkplugs and a Magnaflow muffler. I almost forgot the boost actuator adjustment gave me close to a 1# of that increase. With the bigger pulleys the boost actuator adjustment is barely noticable.



Airbox Mod

 

The Autometer gauge is what $35/$40?
The factory gauge probably cost somewhere in the $1.50 to $2.00 range