so im running a JM fab hood dump 02 housing daily driving it and notice smoke coming from it while giving any gas at all. I thought it wasn't suppose to open unless under boost? is there a leak or is this normal? anyone else dailying a hood dump? thanks

 

Is there any preload (spring pressure) on the flapper to hold it closed tightly?

Could be a gasket not sealing too. I assume this is on a stock style turbo?

There are some gaskets that do not have the block off rail (for lack of better term) to divide the engine exhaust from the O2 exhaust. If that makes sense.

Without the divider exhaust would be able to flow pretty freely out that dump tube.

Pics are worth 1000 words so here is what I am talking about.




O2 exhaust divided from the main exhaust



o2 exhaust is NOT divided.