What improvement would I see by going to an HX35-12 or 16 as compared to my WH1C-16. I currently get a max of 22psi. I'm thinking of changing to reduce mid range smoke. I don't tow just carry an 8 ft cabover about 2500lbs. I currently see a max of 950 post turbo if I lug it in 5th. Will the 16 hsg off my WH1C fit a later HX35 say 98 and under? What year did they change to the flange type exhaust outlet.
Thanks
Dave

 

I did a search, and the info was a little hard to decipher.
1. Is there any advantage to swapping out my stock H1C for a
stock HX-35?
If so, how much?
2. Is there any real difference between these two compressor
housings once they're both modified(like an HX-40 pinwheel)?
Or a PDR H1C vs. PDR HX-35?
All of the above comparisons using the same 16cm exhaust housing.
Thanks, Phil

 

I went form 22# with my H1C-16 to 29# with a PDR modified HS35-16. There were no other changes made at that time so that was a 7# increase just by the turbo swap. I was told to expect about a 5psi increase so I was very happy with the results. The HX35 also spools up MUCH faster. I'f you gonna put an HX35 on, you need to let your truck inhale & exhale better.

Carl

 

The HX35 series has a bit better efficiency map... meaning it will run a bit higher boost numbers and still remain fairly efficient doing it....
Basically it's sort of a half step upward above the H1 series....
The HX's also have a silencer ring that keeps the whistling down..I have never installed one in my hybrid '35 and love the big truck sound....

The 12cm and 16cm housings are a bit different...
If you run a 12cm housing, it is almost always wastegated. That is needed to keep it from overboost or over spinning the turbo.
Also the inlet to the housing gets pretty small with the 12cm so as you work it harder and feed more fuel into the truck she starts to choke up right at the exhaust manifold/exhaust housing connection. You get higher and higher "drive pressures" and the heat that goes with that....not good, especially if you taking your EGT readings AFTER the turbo instead of BEFORE it.
Now the 12cm will spool up rocket fast, it will give you great boost numbers with instant response..
It will also "run out of wind" at the upper end.
The 16cm is not a wastegated housing, and will spool slower.
The 16 will give you roughly 4-5psi less boost total. That is not necessarily a bad thing. You only need enough boost to burn the fuel, any more is a detriment.
The 16cm can be a great housing to run on the highway and will give you pretty much the same air that you'd get from an 18.5cm at the upper end without the lag of the 18.5cm housing.
It is an all around housing for street and highway use.
No matter which one you go for, H1 or HX, 12cm or 16cm make sure you open up your air flow to the max.... eg: filter, airbox etc...

does that help????

bob.

 

So a stock HX-35 is only a marginal upgrade at higher boost levels than a stock H1C.
Well It looks like I'll be looking at either a PDR modified HX-35 or a PDR modified H1C.
Is the PDR HX-35 any better than a PDR H1C??