blocking off the wastegate on 12.7 turbo

It is never a good idea blocking off the waste gate. If the waste gate is blocked closed, excessive back pressure is created on the exhaust manifold you would risk cracking it quickly. The restriction of exhaust flow thru the small turbine housing would create excessive EGT's and possible overspooling of the turbo. You are doing more damage than it is worth. And the risk of being sidelined along the road is not worth it and will cost you a bundle as opposed to what you think you might be saving. The opposite, blocking it open is just as bad. Then you would have lousy spool up and excessive fuel consumption.

You can get a brand new non waste gated BW turbo for under $700 with a factory warranty and no core charge and have all your problems solved quickly. Just bite the bullet and do the job right and be done with it. You and your engine will feel much better. It is a simple plug and play solution that will statistically outlast any wastegated turbo several times over. A couple of hours and you are on your way with greater peace of mind. This is no time to "pinch pennies". By going with the non wastegated BW turbo, you will probably kick yourself in the backside for not having done it sooner.

 

the only way to properly eliminate the waste gate would be to install a non waste gate turbo. I'm sure some guys here could get you some part numbers, the other option would be to replace the waste gate actuator that's leaking.

 

HP rating will decide which BW non waste gate turbo is best. A couple of examples is the 171702 which is for 470-500 hp ratings, while a 171701 is more for 435-470 ratings. Check with a good diesel shop and they can help you out. A dealer or a Detroit branded shop is not the place to go. I just avoided the wastegate thing right out of the gate with my recent glider purchase. Factory remanned Detroit DDEC IV 500 hp 12.7 in it. It is getting a ported, polished, and coated exhaust manifold, a BW 171702 turbo with turbo blanket, before it hauls the first load. The icing on the cake is that it is also getting the factory stack mufflers replaced at the same time with Walker Megaflows, a crankshaft balancer, and getting a Fleet Air Filter. Might as well take care of the intake also. Parts are in and heading to the shop tomorrow to be put on.

 

What's a turbo blanket?

 

A turbo blanket is just a type of wrap/insulation, that goes on the turbine (exhaust) housing to help keep heat in and exhaust flowing better. Benefits are the turbo will spool up faster and a little more boost.

 

Agree, major engine damage can occur if you block off the wastegate. The 12.7 Detroit uses a a Garrett GTA4202 turbo - at least the earlier ones do. This is a decent turbo, but the sometimes wastegate actuator goes bad partially or completely and this can cause surging and low boost at low rpm's. It is easy to replace the actuator on this turbo and they are not expensive. We get our 12.7 actuators here: Detroit Diesel 12.7L Series 60 Turbo Wastegate Actuator Garrett GTA4202BNS - these are good parts - never a problem with them.

 

what size turbo blanket doI need for the 171702 b/w thanks

 

I think a T4 or S300/400 blanket will fit.

 

T6 is what I use.