Will a diablo sport preditor do datalog?

 

Its not the bypass valve, I pressure tested it up to 15lbs and it held shut WITHOUT and pressure on it through the vaccum fitting on the back of it. Especially with the adjusting stud cranked down as far as I did, it would be tough to get that piston to open up without vaccum.

 

But I didn't buy it from you. Maybe Junior adjusted it while he had it.

If its not the bypass valve I hope its the belt. Otherwise, what else could it be???

 

You did buy my bypass valve... just from someone else. I bought it brand new, only had about 1000 miles on it from me. What intercoolers are you running? One my my twins had a leak in it that was definitly affecting the boost levels. I'd suggest pressure testing your system. I disconnected the blower outlet piece then used a hose clamp and a ziploc to cap off that end. Then I used like a 3" or whatever sized PVC pipe cap on the rubber piece coming out of the plenum. I drilled a hole in the cap and threaded in an air fitting and set the compressor to 15lbs and pumped in air. This is how I found the leak in my intercooler and found out that the bypass wasn't leaking.