jrussell

I found a local diesel performance shop today that sells custom 14cm non-wastegated housings that bolt in with no exhaust mods. They take a stock 14cm housing and cut the back off (and maybe machine it) to make it the same length as a 16cm/18cm/21cm.
With the new 4" exhaust I don't have much room to work with and wasn't looking forward to cramming a long-style 14cm housing in there. This was just the answer!

If anyone wants one, give Mark (I think) at Gillett Diesel Service a call. Mods, please feel free to edit/delete if this is not acceptable.

wannadiesel

Neat find!

xtremexj

How much for this modified 14cm housing?

bgilbert

JMO, but I would want a wastegated housing if I went smaller than 16cm.

wannadiesel

With stock injectors on an intercooled truck it would be fine, but you're right that it does not leave much room to grow.

jrussell

Well, according to the info I've read, at my altitude the 14cm is about equal to a stock 18cm housing. My new max boost after installing the housing is only 34psi, so I think it will be ok.

jrussell

With the 14cm housing and 4" exhaust my EGT's only dropped maybe 50*.

I don't get it. Stock injectors and just under 2 turns on my fuel screw and I still have high EGT's, even with the Stage III hybrid and other mods.

Bushy

I strongly agree with bgilbert regarding the use off wastegate on the 14cm and the 12cm housings. They are pretty small and it doesn't take long before the begin to have some pretty nasty drive pressure, a big jump in boost air temperature which in turn will cause significantly higher EGT's.
This is something you obviously want to avoid whenever/wherever you can.
If you use the WG to control max boost levelss you'll find that the smaller housing will help alot and also lower the high temp charge air going into the manifold.

pb...

wannadiesel

Try bumping the timing some more. What is the altitude where you are, anyway?

jrussell

So even with a current max boost of 34psi I should still have a wastegated housing? I hear of people running the same hybrid turbo up to 45psi with a WG housing. Wouldn't 45psi with a WG be a lot worse than 34psi with no WG? I figured with a WG I would still want the full 34psi of boost I have now, so how would a WG help me?

At what boost psi can the drive pressures expect to become a problem with a 14cm housing?

Wanna, I'm at about 5,000' of elevation. The timing was already bumped when I went in to do it. There is just a hair under 1/8" between the two marks. Could I possibly still be timed at the default factory timing if those marks aren't lined up?

wannadiesel

I don't think you need a wastegate yet, 34 psi is not excessive. Adding some timing will lower the boost some, too. 45 psi would be just heating the air, I would not run over 40 psi.

At a mile high it is hard to keep EGT down even on a stock truck. I really think a 12 cm wastegated would be a better housing for you.

Without actually checking the timing there's no way to know for sure where you're at, but it won't hurt to bump it up a little and see if it helps and doesn't sound too harsh.

jrussell

Thanks, Wanna. That's kinda what I figured, but Bill and Bob scared me a little.

What does it usually cost to have a shop check the timing (and adjust if needed)? I don't really want to get into it myself, but I don't want to be overcharged either.

wannadiesel

It shouldn't cost much if you can find a shop that still has the tools to do it. Tell them you want 1.6 mm lift, that's about the max stock injectors should run.

jrussell

Oh, when doing the timing how on earth do you get to that top bolt near the head? I bought the set of S-wrenches from Harbor Freight, but still can't get to that darn bolt.

wannadiesel

I use a socket and long extensions to reach it from back by the fuel filter. 1/4" drive is very helpful, but I have done it with 3/8" stuff.