i have a turbo XS MBC and iam getting some pretty high boost spikes that concern me. Only when i dont downshift does it spike, but it spikes at a bout 23 psi then settles to 20 psi to redline. It holds that spike longer depending on what gear im in. Holds longest in 5th and shorter in 4th etc...

I have the boost controller set up between the turbo outlet nipple and the wastegate actuator. I once had the boost controller teed into the BOV line, but it did the same thing. I have a buschur intake a muffler delete pipe walbro fuel pump, the MBC and a dynoflash.

What my main concern is will spiking to 23 psi hurt anything? it doesnt do it for long, and it only does it wheni start out below 3000 rpm in 3rd 4th or 5th. I jsut dont wanna melt a piston. I also always use 93 octane.

 

This might sound silly, but get a hyper ground kit. It worked for me. A 23psi spike is not that bad, but if you hear detonation which sounds like crumpling potato chips, then turn down your boost unless you have 100octane or higher in. Avoid octane boost supplements. They have additives that cause high EGT temps.

 

i would advise you to turn down the boost so it will spike to 21psi, it's much safer than where you're currently at