I was thinking of getting a 16 cm.ported housing as an upgrade to my stock turbo.I know this question has been asked too many times but,what will it do to my egt's?I tow quite a bit so I dont want it to get too hot.Will there be a whole lot off difference?And,is it really a noticable improvement over the stock one.I found one on another site for $125,is this fair for a piers ported housing?I would look at some old posts but I dont have much time right now.Thanks for the advice.

 

$125 sounds good. I think they're $150-ish new.

you MIGHT actually find that the increased boost and quicker boost response actually keeps EGT's down... I don't think it'll increase EGT's by a ton if it does at all.

your truck has an 18, so it won't be a huge leap, but I think you'll like it.

Forrest

 

i second what forrest said. i really like my 16 for towing.

jiMMy

 

A change from an 18.5cm to a 16cm will help with your EGT's a bit. I'd take a guess at about 70-80*F temp reduction.
The 16 will spool a bit quicker, it will also do something else that is a big help.. it flows nearly as much air at the upper end as an 18.5cm does. In essence you get the benefit of a smaller housing with good air at the top end.
As far as porting a housing goes there is some care needed. If you/whomever gets too energetic you can loose gas velocity as it enters the housing...that will hurt your efforts. It needs to be done correctly is all.
Since the 16 will spool a bit sooner AND provide about another 2-3 psi boost you will likely see that it lowers the RATE at which your EGT's rise too.
These are some of the things I've found in my tinkering.
It won't be an OMG improvement but it will help.
If you have the turbo off, why not remove the manifold too... you can get some polishing done on the exhaust runners and the exhaust manifold outlet too. That will help as well.
Last, if you go that route you'll find that two of the manifold bolt holes are smaller than all the rest... I think they are in/around #3/#4 cylinder. One top hole and one lower hole.
Just find a drill bit one size larger than the existing "small" hole and enlarge the two.
That will help with gasket creep which we all have happen on these trucks....I bet if you look at the exhaust manifold gaskets on # 1 and # 2 cyls. you'll see the gasket protruding out one side or the other of the joint.

pastor bob...

 

Is a ported housing better?I think its a piers so its probally been done right,unless the guy that has it did it.Does this sound like a good buy?I dont want to buy one somebody messed up.

 

I'm sure it's fine... even if it were slightly overported at the inlet, you probably wouldn't be able to feel a difference... and you'd have to extrude hone a lot to hurt the inside of the scroll portion.

go for it.

Forrest

 

if your that worried about it i would ask the guy who did it. if he did it and your leary of his work, spend 25 bucks more and get a new 16cm and no worries either.

jiMMy

 

I ported/polished (conservatively) my 16 cm before I installed it so I can't compare ported to non. I also had no other mods at the time.
But I can say the improvement over the stock 18.5 was very nice.
It lowered spool up rpm by almost 500 which made the truck much more driveable. No more worries about merging into traffic
after that.
I did not notice any significant EGT change but I do not tow.
I did net the boost increase that Bob mentioned.
Go for it...you'll like it a lot!!
Jay

 

Would I notice a big difference in mine (21cm housing, stock) no power at low end
and does it affect fuel mileage at all? I'm getting about 22/23mpg now and dont want to loose any.( 53 mile commute one way )
Thanks in advance, Michael

 

You will notice a big difference in spoolup, but you won't have any extra power once it's spooled up, and economy shouldn't change with the 16 cm. The improved spoolup should allow you to advance the pump for better mileage without the truck being so doggy.

 

I ran a 16cm and it did spool alot better than the 18.5cm. Then I ported the 16cm and it spooled a little faster. The 16cm still smoked too much for me.

I now run a ported 12cm W/G with the W/G hole drilled to the other side so all 6 cyl. get dumped. The smoke on spool up is much improved compared to the 16cm. EGT's are about the same if not a bit better, and it spools lightning fast. I can still get to 1200* easily, but it seems to take more time than the 16cm did.

I'm not trying to talk you out of a 16cm. But consider a good used hx35/12 can be had for about 200-300 dollars. A better turbo IMO than the h1c.

 

O.K,here is a dumb question.The one I am thinking of getting is a 16cm exhaust housing, this is the same as a turbine housing,right?

 

to me a turbine housing woul dmean just a turbo with no guts. teh exhaust housing would bolt to the turbine housing. but thats how my mind is turing. jiMMy

 

the exhaust housing is the turbine housing... the compressor housing is the aluminum scroll that houses the compressor wheel... the cast iron turbine housing houses the turbine

 

Alright,Thanks alot.I wanted to make sure I was getting the right one!