adding a blow off valve?

um......I'm going to go with no. What are you doing with your N14 that your causing compressor surge? Floor it and lift?

 

I've never heard about overboost problems with N14. There is no boost pressure liming valve.

Usually overboost codes are related with faulty boost pressure sensor wiring ore faulty sensor.

 

Getting any BOV to even remotely work on an N14 would cost more than 2 turbos. I've never seen one work right on a diesel pickup and most guys who bought them did so because of severe barking issues and wouldn't buy another. The diesel versions have to be set up and tied to the throttle position sensor and hardly ever work right.


Long story short, save your money. N14 turbos are not that expensive and usually last a long time if you keep your oil changed and clean air filters.

 

Never heard it referred to as 'barking' before. lol

Since I put a new CAC on my truck...now it boosts up to 40-41lbs and if I let up too quick when I shift, the turbo will 'flutter'...you know, sounds like "fooo-toooo-tooo-tooo".

 

I think when it does that you basically have the turbo working against itself. It's normal in the sense it's just how it works. When you let off the gas, there's not enough exhaust pressure to keep the turbo spooled up and the boosted intake air has to escape. The only way for it to escape is backwards from intake manifold, thru air cooler, turbo and back out the air cleaner.

Maybe the experts have a better explaination.

 

Diesels don't have a throttle butterfly that closes on boost pressure and causes a spike....

If they did, the spike from 35# of boost at WOT would turn the I/C inside out.

 

The gas guys use them to vent the boost between shifts to reduce lag, but most just buy them for the noise. Diesel's usually don't need one and are a PITA.

I know a lot of guys with modded diesel pickups and the auto's are the worst. Automatic transmission and large single turbos will surge sometimes between shifts, or at lockup. Most just learn how to drive to minimize it. With my manual transmission I had to try to get it to do it. With twin turbos it's almost impossible.