Get this...

Yesterday I swapped my 16cm2 Wastegated Turbine Housing for a NON-Wastegated housing...I wasn't going to use the wastegate anyhow, plus I would have had to cut my downpipe about 1.5" to clear the wastegated housing, putting the downpipe nearly into the firewall.

I popped off the H1C, and noticed that my turbine housing is stamped "18.6cm" What the heck is that? I thought 1992's came with 21cm2 housings?? 18.6? Never heard of it!

So I bolted up the fresh HX-35 and the 16cm2 housing...after priming it, checking all nuts & bolts one last time, and giving it 10 minutes of idle time to make sure there were no leaks of any kind, I went to take a test drive but my headlights crapped out again.

I took the truck out today and it makes the LOUDEST darn noise I've ever heard. Under boost this turbo wails louder than a big rig...everyone standing outside would stare as I drove by.

Boost is down...used to be 26psi max with the H1C...now it won't go past 23psi....???

The 16cm2 housing has made a difference in spool up, I can see and feel that, but the turbo isn't quite doing it's job. It feels like it did before we tweaked the pump, it just doesnt have that "pull" that it did with the stock turbo.


I've rechecked all the connections & fittings of the charge air pipes...and have come up with only 1 conclusion. There is a pretty good gap between the compressor wheel and housing. maybe .050" instead of the normal .025". When I built this turbo, it was "Frankensteined" from a pile of Holset stuff, and I was originally planning on machining out the compressor housing for an HX40 wheel, but wanted to try the 35 first.

What do you guys think? I don't think the gap could make that kind of noise and power reduction...but I don't know. Maybe I need to try another compressor housing that fits better. I've noticed when building HX35's that some housings and wheels don't match up the same.

I'm considering bolting my H1C back on the truck, but using the 16cm2 housing...and seeing if that brinng my power back.

If so, I'll be building another HX35 or 40...

 

Jeremy,

where did you find a 16cm2 wastegated turbine housing? wanna sell it? my twin turbo setup is built around an HX35 wastegated turbine housing... I've got some different HX stuff if you're interested... 14cm2 wastegated HX35 housing, some HX35 and H1C cores, and a 61mm 6 blade HX40 w/ a 16cm2 turbine side on it (wastegated)

it definately looks like you've got some excessive clearance there between the wheel and housing!!!

also realize that if you want to run an HX40 wheel on an H1C or HX35 center housing, you'll need to machine the housing to allow the major diameter to clear.

we built my HX40 using H1C center and compressor housings machined to match the wheel

oh yeah, and your '92 had an 18.5 cm... the 91's and earlier had a 21

Forrest

 

oh yeah... couple more things...

the HX35's and 40's are a lot louder than the H1C's because of the MWE slot... you should hear my 40 in the 20-30psi range! straight up 18 wheeler!!! in the 35-40 range, the 5" straight pipe kinda takes over, but the turbo's still screamin'!! LOL!

and...

I'm in Dallas... I'd really like to talk w/ you about that 16cm wastegated housing!

lemme know,

Forrest

 

Forrest, Cummins2fast (aka Deezul1) swapped me his NON-gated 16cm2 for my 'gated 16. So now he has it. What he didn't know was...his truck had a wastegated 16 on it already, he thought it was a 12.

According to all the tech sites and stuff on the internet, they say my truck has a 21 stock. Mine was an 18.6, weird.

Maybe you can get that housing off Cummins2Fast...although Cody (NeedMoPower) might have dibs on it.

 

well...something isn't right. The turbo noise is pretty excessive...but the power isn't there. Not as much boost, not nearly as much power.

 

Like Forrest said, the clearance between the impeller and the housing is way too big. You need a bigger wheel or a smaller housing. I noticed a huge difference in sound when I changed from the '92 H1C to a '94 WH1C, the MWE slots that the silencer ring covers really make a difference in how loud the turbo sings. Mine flat out screams at the top of 4th!

 

Dave....what about the power....is it suffering from the clearance gap as well?

 

how are you reading/measuring the 16cm wastegated housing? if you're looking at the raised numbers cast into turbine housing on the OUTSIDE of the housing, you've probably got a 12cm housing... I thought I hit the goldmine while digging through the bins at my local turbo shop... 16cm wastegated housings galore!!! and then my buddy said, "nah dude, you gotta look on the inside... those are 12cm housings"

and yes, performance is suffering big time from the clearance... use an exaggerated example... imagine if you took that same compressor wheel and put it in a T76 compressor housing... think it'd work very well? the tighter the clearance the better... ball bearing turbos can run tighter clearance because the shaft doesn't have as much radial or axial play... that's part of why they spool up quicker... the reduced friction is part, but not all!

Forrest

 

What he said. Also I'd be concerned about overspeeding the turbo because the wide gap lets everything spin too freely. When I got my WH1C I was going to just swap compressor housings until I noticed how big the gap was with the WH1C housing on the H1C.

 

well Edited on me. In that case...the turbine housing I installed is an 18, as what was stamped on the inside.

GREAT

Edited By Admin Please review the rules you agreed to when joining this website, particularly in reference to "Profanity"

 

LMAO!!! sorry, but "**** on me" cracked me up!

anyhow, yeah, you gotta look at the numbers cast into the inside of the inlet portion of the turbine housing... it's POSSIBLE that you've got a 16 and it just looks kinda "cloudy" and looks like an 18... my 14 is kinda hard to tell... we had to sand blast it to be able to read it right.

and as Dave pointed out, you gotta be careful swapping housings/wheels/etc. For some reason Holset decided it would be fun to make about a zillion different H1C wheels, a zillion and a half HX35, and about 3/4 zillion HX40 wheels... sometimes it was just a different number and or pitch of the blades, but often it was a different diameter wheel, and there are many different diameter wheels!

The Holsets are great turbos for high pressure ratios, but they sure don't like to make it easy on a fella!

Forrest

 

According to our Tech References..."3521927" is the part number for the 16cm2 housing.

I just went out and checked...Mine says "3521834" which isn't a part number listed on the Tech page "http://www.dodgeram.org/tech/dsl/FAQ/turbo_faq.htm"

Tonight I'm going to swap the HX35 out for my H1C and see how it goes.

 

not sure about the part numbers... like I said, Holset doesn't give a guy much help when it comes to mixing and matching! LOL!

Forrest

 

Welp, I just swapped the HX35 out for my H1C.

BOOST IS BACK!

The housing MUST have made a difference, so it must be a 16cm2, cause boost comes in as soon as the go-pedal is put down...no more lag.

The insanely loud noise is gone, and I'm up 1# of boost overall.

Oh yeah, I gave the H1C a fresh coat of BLACK, so it looks nice now.

Looks like I'll be doing some machine work to the HX35 now and installing an HX40 compressor wheel

Thanks for the replies and info guys! And sorry about the vulgarities in the previous posts. (I was a bit ticked-off)

 

3521834 is the part # that was on the 16cm that I used to have.