I am getting boost drop at about 7-8 psi. Boost climbs normally then suddenly drops about 1 psi then holds there to red line. Is this more likely belt slip vs a hose leak somewhere.
SOS kit stage 2. 10 psi pulley.

 

Those are pretty much your 2 option for losing boost on a supercharger.

 

I had the same issue yesterday! I was at 390hp on around 6psi then drop down to 385hp lol. My tuner suggested to get electronic boost control

 

Check your belt tension and couplers. I've had some good luck with spraying hair spray in the couplers (let them dry for a few hours) and using t-bolt clamps.

 

Ok, but how do the two problems show differently on my flashpro datalog for boost? If it was a leak there would be a constant loss from 1-6 and no spike right? Problem is, my belt feels tight. I can turn it but not easily

 

If the belt is at the proper tension, then you may be leaking at the coupler fittings.., that is about the only two things that could be leaking, pretty simple systems. If you are not using the upgraded clamps, I would suggest making that change...and also as mentioned before hairspray does a pretty good job of making the seal stay sealed.

 

Ooh i like the hair spray trick. Good to know

 

Got it. I'll try those and report back.

Also I relocated the air temperature sensor to right before the throttlebody. I made a small hole in the rubber coupler and just stuck it in. That's how it was installed on the intake side before the supercharger which is in vacuum but on this side it is in boost. Do you think air could possibly be getting pushed out through that hole past the sensor? Would I use some sort of silicone to seal that up?

 

Update: took out ait sensor, taped up hole, still same boost drop. Got smaller belt, will install and retry. SOS said it's definitely sounding like belt slip, heating up and re catching .

 

Update; belt still slipping , tightened the smaller belt until the tensioner pulley got a little off, allowing the belt to hang about 2 mm off the edge, and that ripped the belt. Got new belt, still slipped, tightened it and I can see a small groove wearing in it where it was hanging off the pulley edge. Any ideas from here? I plugged all the intake holes, switched back my air temp to the vacuum side in case that was losing boost, I don't know what else to try.