This is what I was gonna say. Looks excellent. Non intercooled you'll be seeing more boost than a typical IC'd truck. Be ready to clean your shorts the first time you blast off one of those boots !

 

Ford/International 6.9 engines, being a V block, have an intake chamber, much like a carbureted gas engine.

There is a hole, about an inch diameter, at the fire-wall side of this chamber that has a rubber expansion plug fitted in it; I am told, this plug is meant to blow from excessive boost, before something else goes.

I was cruising along across Iowa, in a snow-storm, with a trailer-load of cattle, when BOOM!!! , that stupid plug blew out.

I first thought I had ran over a mine.

I then noticed the boost gauge laying on zero, and the truck not nearly as powerful.

I would probably still be looking for the problem, if I had not noticed the rubber plug laying in the valley, between the heads.

When the plug went back in, it was sandwiched between two large fender-washers that were much bigger around than the hole; I didn't want any more un-expected explosions.

 

Try spraying the inside of the boots with hairspray if you pop one off. Once it dries it kinda glues them on.

 

Looks like a very good setup.


Ideally the setup would give you a drop in boost pressure, right?

 

that was my first thought...

all else being equal, putting the same amount of air through a bigger tube would be less pressure...

EXCEPT that since the gauge is not hooked to the crossover tube, I'm pushing the max volume I could get in there, and it's being measured once it hits the motor...so, it could possibly actually be an increase in boost?

either way in theory...it actually showed basically the identical boost readings after the swap...

Greg

 

So what would really be the improvement of the modification? Since the manifold into the engine is the same, wouldn't the turbo still have to work as hard?

The pipe would be smoother, but it's still got to go through the same hole, right?

 

Clearing up restrictions along the way will still help flow through the system as a whole.

 

that was pretty much my thought...the opening in the grid heater is bigger than the opening in the end of the OEM crossover pipe...didn't pull the heater off to see how big the opening to the intake manifold was...

it's a $50 shot at making sure the stock crossover is not a bottleneck for the airflow...

plus, it'll be a nice spot to add W/M down the road...

Greg

 

I hope it works, which it should. Shouldnt be any more pressure on the elbow than on the adaptor to the Turbo. I know one thing....Im gonna copy it

 

That surprises me. What kind of boob engineer would be responsible for that?

(Must have been a Dodge engineer, not a Cummins engineer...)

 

I just went and measured to double-check...and the bottom of the OEM crossover is exactly 2" square...

I don't have the grid heater measurement...but edwinsmith was helping me out on a design awhile back, and he had measured it to me 2-15/16x3-1/16...

almost an inch shorter in each direction...which is why we thought the 3" roung pipe would be a good fit...

Greg

 

Well, that means here is something else on the list...

 

Waylon,

How much, if any, EGT drop have you seen with the bigger/better crossover pipe??

EGT-wise, how does it compare with a comparably modded factory intercooled engine??

Thanks.