Just some thing i need to know.... What happens when a turbo is over boosting?

 

If your motor isn't tuned for those higher boost levels it goes BANG! Which is usually followed by a cloud of smoke in your rearview mirror and if you're really unlucky a puddle of oil on the ground from the hole in your block.

You can also over rev your turbo. For example if you took off one of your charge pipes it wouldn't build boost, the wastegate wouldn't open, and it would spin to much from the excessive exhaust which in turn can damage the turbo.

 

I only ask cause my friends greddy internal wastegate only opens up partially half way. So he unscrewed the nut that was connected to that piece of rail, and let it loose just a bit so the wastegate opens up just a tad bit more. Would that be unsafe. He is gonna get it tuned by the way. But can he still be over boosting after tune. Is it possible.

 

and before this he was only boosting 5psi.

 

He will want to tune it for the additional boost like you said. I had a GT28R long ago that had an internal gate. I remember adjusting the nut on it and getting a few more psi out of it but that gate sucked!

I don't know enough about internal gates to give you any good advice on adjusting it. Maybe someone else has more experince messing with those.

 

any other takers that might know?

 

what i used to do a back in the day to my buddies t2 rx7, was port the stock wastegate with a rotary tool to make the wg larger and weld a washer to cover the larger area. the wg will flow more.

the older rx7's that was a common problem with aftermarket dp's and exhaust installed.