partisan1911

I have a set of BD twins in my '05. They have been constant trouble since I put them in. The clamp behind the top turbo always leaks and it is inches away from the firewall. Funny that they call it a "firewall". The leak caused that cloth material on the firewall to catch on fire. It was a PITA to put out. Once I got it all fixed that clamped area still leaks and I see it is slowly burning away the firewall material again. So now I have put some napa bought exhaust wrap around that area.

Will that exhaust wrap hold up or will it catch on fire? When I operate my exhaust break, even more exhaust fumes escape which puts additional heat focused in that area.

I have also noticed my EGT's went up an extra 100 degrees than normal operating temps.

soulezoo

The hot pipe should have already been wrapped from BD. Yes, it will hold up if you got the stuff I am thinking of.

The leak you describe is either from warpage or simply not smooth surfaces between the clamped area (check that both surfaces are level and free of defect) or even the wrong clamp. A too big clamp is common.

What you are experiencing is not unusual. Another thing you can do is fashion a metal plate and bolt to the firewall as a heat shield, or use a fat sheet of heat shield (the sticky stuff) and tack that onto the firewall.

Twins on the low end of operation often exhibit slightly higher operating egts due to extra back pressure when working with smaller twins or due to a little less intake airflow from the larger turbine and exhaust housing (and to a lesser extent the compressor wheel map-- bigger compressors start to make air later than small ones), but make it up on the top end where more air keeps things a little cooler.

What BD twins do you have?

CD in NM

Sounds like your hot pipe clamp is not right, not fit right. You can get some of that 1/2" or 3/4" wide stove pipe gasket material and put it in the clamp area then put the clamp over it, tighten it up, and your leak should stop. Having that leak means you are loosing the power of your exhaust brake as well, it will work much better after getting the leak stopped.

Then, wrap your hot pipe with exhaust wrap, that will also cut down on the heat at the firewall. When I installed my twins, I wrapped the hot pipe with the exhaust material and then sprayed it with ceramic exhaust coating, those two things combined make for a really nice heat shield.

I removed all the factory firewall insulation material and installed the aluminum faced insulated stick on heat shielding. I also removed the factory hood insulation and installed the aluminum faced insulation material on the entire under hood area.

It really changed the heat problems for both the firewall and hood and also cut down engine noise. I bought enough to do the entire inside of the cab as well, have that all done too, what a difference in road noises, almost none to speak of now. Def a good investment.

I used the Fat Mat Rattle Trap insulation and sound deadening products. They are every bit as good as if not better than Dynamat products at a fraction of the cost.


If you PM me with your e-mail addy, I will send you some pics of how I did my wrap and also how I used the exhaust wrap materials to protect that small wire loom that runs across the top edge of the firewall.





CD

partisan1911

I have the BD super B twin kit.

CD in NM- You wrote a pretty good description of what you did to your truck. I was hoping not to go to that extreme but I guess it may be necessary.

I have been wanting to pull the system out again and use feeler gauges to check all the mating surfaces. I bought and gone through several different clamps through BD. I even bought their stupid exhaust because I let them talk me into thinking that somehow the stock stuff was twisting the piping just right.

Unfortunately I won't have time to pull the equipment out for at least another year and a half because I need my truck. I know as soon as I start pulling my truck apart; something will break and I will have to place an order.....get the wrong part...place another order.

metal_miner

I had a BD twin kit and had the exact same problems with exhaust leaks.

BD used an HX40 style outlet on the Super B, which was smaller and had less sealing surface area than a 3rd gen style turbo exhaust flange.

The BD primary turbo support was also kind of flimsy, which cause the primary to move a bit relative to the solidly mounted secondary turbo. I ended up having to weld up additional bracing to the turbo mount.

The additional bracing helped a lot, but wasn't the cure all. At the time I didn't know about the stove pipe gasket trick, but tried exhaust header wrap or thin copper flashing between the clamp and hotpipe/turbo to get a better seal.