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My HX40 install

Question about the waste gate actuator. I see on the new turbo that you are using a port on the turbo output side to control the waste gate. How do you control the amount of vacuum on the waste gate solenoid ? I have a 93' that is currently mechanical, a big spring with an adjusting nut. I am guessing your truck originally had a vacuum pump, that everyone wants to get rid of, for control of your gm8 turbo.
 
There is a spring inside the actuator that holds the wastegate closed. The pressure inside the outlet housing going through that blue hose works against that spring and when the pressure is high enough overcomes the spring pressure and lets the wastegate open. That wastegate is factory set at 20psi. When I had the turbo apart I turned the actuator 1/2 turn to try to drop that pressure. The highest I have seen it boost is 18psi so either the half turn dropped the open point to there or I don't have enough fuel to boost it higher. We'll see what it does when I get the new engine in it.
 
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Ok, that was the only part of the installation I did not understand from reading yours and many others. Pretty sure I pull it off now.
The lower temps alone, make it worth it, and then the gains in performance +++ You said something never thinking you would do all this work on your truck and I have said the same thing several times. I have learned a lot and enjoyed it at the same time. Thanks for your great write up. Looking forward to hearing about your new engine when you get it set up.
 
Ok, if you've been following my engine build thread, then you know that the coolant in my engine oil took out the shaft and bearings in the HX40. Since it didn't cost that much more to just get a whole new turbo rather than fix the old one I went that route. Unfortunately, they raised the price on the EM USA turbo I bought before by $100. So this time I went with the JM Turbo. Right off the bat I could see that it was packaged better. I took a lot of pictures last night of the turbo.

The turbine housing has the same "18" cast into the inlet of it as the EMU turbo so I have to assume the housing size is the same. The JM Turbo housing is a different casting though because it is missing casting IDs that the EMU housing had.
JM HX40 Turb Hous.jpg HX40 Turb Hous.jpg

The turbine wheel is the same in both the JM Turbo and the EMU Turbo - same number of blades and the same large and small diameters (again, sorry about my lack of turbo terminology).

JM HX40 Turb L.jpg JM HX40 Turb S.jpg

One major difference between the 2 turbos is the Compressor wheel. The EMU turbo had a 7 blade Compressor wheel and a bigger large diameter. The JM turbo Compressor wheel is an 8 blade wheel. I'm not sure what difference this will have. I may try swapping wheels and getting the turbo rebalanced in the future, but right now I just need to get the turbo together.
JM HX40 Comp L.jpg JM HX40 Comp S.jpg

There was another surprising difference on the Compressor side. When the Compressor housings were side-by-side I noticed that the EMU housing had a larger gap internally than the JM housing. I guess the larger gap would give more flow? I have no idea. I did cut the V-band off the JM housing and installed that one. I figured it was good to start off with the housing that was intended to go with the wheel to start and then later I could try the other housing to see what difference, if any, it made. I did verify that the EM housing cleared the JM wheel fine, so there's no issue there should I try that in the future.
JM HX40 Comp Gap.jpg HX40 Comp Gap.jpg

The center section of the turbo appears to be the same casting on both turbos because it had the same casting numbers on it.
JM HX40 C.jpg
 

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  • JM HX40 E.jpg
    JM HX40 E.jpg
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Here are some overall pics that I took before disassembly
JM HX40.jpg JM HX40 E.jpg JM HX40 ID.jpg

The JM turbo also came with a balance sheet, which the EMU turbo did not. I need to compare it to the sheet that FellowTraveler posted to see if it's exactly the same or if it does appear to be unique to each individual turbo.

JM HX40 Bal Sht1.jpg JM HX40 Bal Sht2.jpg JM HX40 Bal Sht3.jpg

Since I forgot to post oil fitting pics during the initial install, I took some last night to show what is needed for adaptation. The silver fitting is the metric o-ring to 1/4NPT adapter fitting and the brass fitting is the original oil fitting off the GM8.

HX40 Oil Fit1.jpg HX40 Oil Fit2.jpg HX40 Oil Fit3.jpg

Oh and maybe you noticed that the turbine housing had turned kind of blue....so I guess it got a little hot:rolleyes: Check out the adapter paint though...I think it's a real testament to the DEI exhaust paint that I used, it really holds up to heat!

HX40 DP Paint.jpg
 
And finally....I had been thinking about Great White's comments about separating the turbo exhaust outlet from the wastegate outlet. I didn't want to cut and modify my downpipe adapter too much, but I figured that I could put a divider in there that would at least do a little separation at the outlet surface so I went ahead and made one. I just cut a small section out of some leftover 3" exhaust pipe that I had. I don't know if it will help much but it can't hurt, so I went for it.

HX40 DP Div1.jpg HX40 DP Div2.jpg HX40 DP Div3.jpg HX40 DP Div4.jpg HX40 DP Div5.jpg HX40 DP Div6.jpg

And now the new turbo is assembled and ready to go on the new engine. I think it will be fun playing with the compressor housings and maybe eventually different compressor wheels. I'm making too many changes to the engine to be able to tell differences between the two turbos right off the bat, but I should be able to tell compressor differences in future testing.

Oh, I forgot to mention that I used the old turbine housing because I had already knife-edged the inlet and the wastegate that I had previously adjusted was still attached.

JM HX40 Done.jpg
 
Here are some overall pics that I took before disassembly
View attachment 44668 View attachment 44669 View attachment 44670

The JM turbo also came with a balance sheet, which the EMU turbo did not. I need to compare it to the sheet that FellowTraveler posted to see if it's exactly the same or if it does appear to be unique to each individual turbo.

View attachment 44671 View attachment 44672 View attachment 44673

Since I forgot to post oil fitting pics during the initial install, I took some last night to show what is needed for adaptation. The silver fitting is the metric o-ring to 1/4NPT adapter fitting and the brass fitting is the original oil fitting off the GM8.

View attachment 44674 View attachment 44675 View attachment 44676

Oh and maybe you noticed that the turbine housing had turned kind of blue....so I guess it got a little hot:rolleyes: Check out the adapter paint though...I think it's a real testament to the DEI exhaust paint that I used, it really holds up to heat!

View attachment 44677

From your turbo test sheet your turbo has about 40% + less vibration than mine!
 
Hmmm that is interesting. I wonder how many variations they have.
I just reviewed JM's web site it is changed to reflect your turbo specs and no longer shows cross reference to replace the Holset Super 40 HX for the newer Ram applications I suspect that is the difference on the compressor side of larger minor diameter of 64mm makes it a CKO Super 40 HX 18cm 2 replacement like mine is however the Real Holset Super 40 has the smaller compressor wheel as you have and a higher flow turbine wheel so it is a guessing game..
 
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Broke it down when I bought my JM-D-3-4 is was billed as replacement for Holset # 4027888 the JM-D-3-8 is now the CKO replacement for Holset Super 40 HXw 18 cm 2 # 4027888 for 2001 to current.

My compressor inducer 'minor or air in' diameter is the same a the turbine exducer 'minor or exhaust out' 64mm.

Your turbine outlet is it stamped with 18 on the inside, or?
 
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Broke it down when I bought my JM-D-3-4 is was billed as replacement for Holset # 4027888 the JM-D-3-8 is now the CKO replacement for Holset Super 40 HXw 18 cm 2 # 4027888 for 2001 to current.

My compressor inducer 'minor or air in' diameter is the same a the turbine exducer 'minor or exhaust out' 64mm.

Your turbine outlet is it stamped with 18 on the inside, or?

Interesting. When I was searching for a replacement for the EMU HX40, I was searching for interchange number 3538232, which this one showed in the Ebay listing. Yes, this one is the JM-D-3-4.
http://www.ebay.com/itm/HX40W-SUPER...=cb9e5cc3654b4556b53958b55fb84342&pid=100102&

Oh well, even if it is smaler it will be interesting to do some comparing and contrasting in the future. Or maybe smaller will work better? Maybe it will be worth trying a Wicked Wheel in the future too?

Regarding the "18" in the housing, yes it has that. It was the same as the existing housing in that regard so I didn't take a picture.
 
Interesting the two different compressor housings I'm digging to see if the larger spaced one flows more.

No matter which one it will be way better than any other CKO IMHO.
 
Hey Nate just saw this thread for first time since you linked it from another I was watching. Anyway nice work on bat tray. I just got my tray in today and will be doing something very similar.
 
Hey Nate just saw this thread for first time since you linked it from another I was watching. Anyway nice work on bat tray. I just got my tray in today and will be doing something very similar.
Thanks Leroy. I think it's a better use of the space. I just need to make an airbox to properly enclose my filter.
 
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