Guys, I'm doing the non-sequential mod in preparation for my BNRs and I am following the directions from the Lightning in a World of Thunder site. Steps 36 and 37 are:

36) Open the pre-control gate approx 90% and have welded in this position (you want the gate to be opened and be even with the turbine chamber flow path..IE less exhaust drag). The weld goes around the base of the lever that the pre-control actuator clipped to. DO not weld on the inside of the turbine housing in any way, shape or form, and do not simply tack this as it could come loose.

37) Take the exhaust housing and grind off the gate's outside lever, and then the welds from the washer which is welded to the exhaust manifold. The washer should either fall off, or can be pried off. Then drive out the sleave (from the inside going out towards where the washer was) and lift out the control gate and throw away.

Am I reading this right? Why do you need to weld open the precontrol door in step 36 if you are just going to remove it in step 37? I'm not sure I understand.

Also, does removing the door improve performance much? It would seem like it would help because it would open up the exhaust path a little more and be a little more free flowing.

As always, TIA!
Brian

 

i broke the rules! heh. i pulled out the gate completely, put a plug in, and welded it closed on the inside and outside. I was assured its not going to come loose and shoot through the turbine, but i don't know if you want to take the same risk. good luck!

 

step 36 is referring to the precontrol, mounted on the turbo housing and step 37 sounds like the turbo control actuator which is mounted on the manifold, but i could be reading this wrong. i just installed a new set of turbos and manifold with these mods, including more extensive porting and i can say they do seem to spool faster and the exhaust does seem to be a little bit quieter. i had to open my manual boost controller to get the same amount of boost i was running before, so they do seem to flow better.

 

Okay, so if BNR is rebuilding my turbos to NS, I can pretty much ignore step 36? (Or I should at least check to make sure that they are set up properly!) Thanks again.

 

yes i believe they will take care of it.