H1C vs. HX-35 map

[sparks57]

Does anyone here have the specs on the mapping (and all the other important specs) of the h1c versus the hx-35?



Trying to build a turbo that will eventually be the top to my twins... and wondering what the difference is between the two. I have an H1C on hand...

 

[Forrest Nearing]

for a mild setup, an H1c should be fine... you should only be running your top turbo at 20-30psi

 

[sparks57]

I'm a nitt-picker with my truck, gotta have the best... I don't want to waste my time on an inferior turbo, so I just wanted to know which is best... or if they're the same.



The only reason I was curiouse about the H1C is because I have one on hand. I also have access to an hx-35.



What are the differences? I don't have any experience with the HX-35... so any info would be appreciated.



The compressor will be honed out, basically a 35/40 setup, and a 14cm housing will be on the backside. In that trim, would either be any better than the other? Since I have access to either, whichever has the slghtest edge wins!

 

[Forrest Nearing]

the only difference is the compressor wheel... my HX40 started out as an H1C...



the center section and turbine wheel are the same between an HX35/HX40...



how much power are you looking to make?



Forrest

 

[sparks57]

450-550.



I reworded my reply to be a little more to-the-point.

 

[Cooker]

the center section and turbine wheel are the same between an HX35/HX40...

Where did you get this information? Are you certain this is accurate?

 

[sparks57]

It looks like my H1C will become a 35/40 after all!



What, specifically, needs to be done to it? I know updated bearings are needed (it needs rebuilt anyways) and the compressor housing needs hoaned out... but what else?

 

[Forrest Nearing]

yes, I'm certain it's accurate... like I said, my HX40 started as an H1C... machined the compressor housing and backing plate to fit the HX40 compressor wheel, then couldn't find a 14cm wastegated or 16cm turbine housing, so I took an HX40 turbine wheel and stuck it in there making a full HX40 out of it.



Parker, the differences are the compressor wheel and compressor housing... also, most H1C's use a v-band compressor connection to the backing plate... most HX35's use a big snap ring. I prefer the v-band. much easier to work with, re-clock, etc.



honestly, if you're only looking for 450-550, I'd get it running w/ the H1C on top... like I said, you should wastegate the top at ~20psi or so. an H1C is in the heart of its map right there.



Forrest

 

[Cooker]

yes, I'm certain it's accurate... like I said, my HX40 started as an H1C... machined the compressor housing and backing plate to fit the HX40 compressor wheel, then couldn't find a 14cm wastegated or 16cm turbine housing, so I took an HX40 turbine wheel and stuck it in there making a full HX40 out of it.

Forrest,

So what exhaust housing are you running? If I remember right you are running a wastegated 16cm housing which is from an HX40 so certainly and HX40 turbine wheel will fit in it because it is from an HX40.



I understand the cartridge is the same, however the turbine wheels are not.



Maybe you remember back when with Kurt Yardly was selling Kwikspool HX40's (a 40 with an HX35 exhaust housing) the HX35 exhaust housing needed to be machined to fit around the HX40 turbine wheel. The 40 wheel is too large to fit into a stock HX35/H1C housing.



Therefore the turbine wheels are not the same between an HX35 and an HX40.

 

[Forrest Nearing]

oops, I mistyped... I meant HX35/H1C... same turbine wheel... only difference is in compressor wheel and housing. same bearings, center section, etc.



HX40 uses a different turbine wheel



sorry for the confusion, my fault!



Forrest

 

[Cooker]

CB,

Sorry to get off topic. We just had to clear that up so the readers of this thread are properly informed.



I agree with Forrest's comment on the H1C working fairly well as a top turbo in a twin setup. The HX35 breathes better on the top end and doesn't map out as quickly as an H1C but in a twin setup these are not really big issues.



This is all assuming you have an H1C from an intercooled 1st gen truck, 1991. 5 or later. The early 1st gen H1C's had a smaller intake, compressor housing, and compressor wheel. Also the oil feed line threads where different.

 

[RonA]

CB.

The 35/40 3B combo does 500hp pretty easily. I went with the Dodgezilla on top but they are all similar. Egt is low and spool is good.

 

[BushWakr - RIP]

I would agree with Ron here.....

My brother just had PDR twins put in his 92. He is using a PDR HX35 with a gated 14cm on the hot end.

The HX, in my opinion, is a better platform from which to start your build. Comparing the maps of the two turbo's you mentioned, the HX is certainly ahead of the H1 model.

Yes, you can machine both, but when I go to twins, I'll do the same as my brother... and I have an old H1 holding the basement door open as a spare.

Just my thoughts.....



pb... .

 

[Forrest Nearing]

if you're going to build a hybrid, there's no reason to start w/ an HX35... build it w/ the H1C... you'll have less money in it and it'll be the same turbo in the end.



if you can put your hands on a cheap HX40 for $200-300, grab it, and swap the H1C turbine wheel in it, and you're in business.



forrest

 

[JLEONARD]

Correct me if I'm wrong, it's really the backing plate that gets turned to a larger diameter to accept the larger compressor wheel.

We just recently upgraded my son's WH1C from his 94 using the HTT stage III compressor.

To accomplish this he needed an entirely new housing as the wheel is not only larger dia, but wider as well.

Or are you saying that the housing can also be machined? Didn't look like there was material available in the housing... at least not for the wheel he bought. Plus it looks like a tricky job.

I ask because I have his old housing and am planning to use it for an upgrade to my non/I/C H1C.



Jay

 

[Forrest Nearing]

the compressor housing can be machined, but it has to be done by someone who knows that they're doing... IE, a turbo shop who has the correct lathe setup. My H1C compressor housing has a 61mm HX40 compressor wheel in it now

 

[sparks57]

Very good info... now I just need to read it a few times so I can absorb it!

 

[JLEONARD]

the compressor housing can be machined

Ok. Makes sense. Probably need the CNC program.

The wheel my son put in is 60 mm.

A silly millimeter smaller :-laf

Jay

 

[dpuckett]

... . Also the oil feed line threads were different.

Is that from the H1C to the HX35, or to the HX40? The adaptor threaded right into the HX35 from my old H1C, and the oil supply line (both the old one and new one) threaded into it.

Daniel

 

[Forrest Nearing]

no need for CNC... just a correctly set up lathe and use the compressor wheel as the cutting guide. bottom line is have a pro do it! LOL!



Forrest