The 2H/12H-T/1HZ/1HD-T/1HD-FT Gturbo Alternative Tech Thread

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IanB said:
I'm not saying @Dougal is wrong about the compressor surge, but this testing would lead me to suspect my MBC as well. The Dawes unit @gerg mentioned above is a lot cheaper than rejigging your turbo, worth a try IMO.
Click to expand...

I'm open to trying another MBC. I bought the HALLMAN Pro setup, as I was told it was the best setup at the time for some reason that I can't remember at the moment. It did come with a heavier spring, maybe I'll try the heavier spring on a low setting and see if it makes a difference.

I know a few other people bought these wheels a few years ago, anyone seeing the same surge? Paging @lynchmob @HDJDub @Malahki

Thanks for the help
 
tweeek said:
This is somewhat what I expected to hear.

Can you elaborate though on your comment about the wheel being to big for the boost I need at low rpm? In my case this fluctuation is happening at high rpm, the attached video would be above 3000 rpm.
Click to expand...

3000rpm changes the diagnosis a bit.

I would fit a restrictor in the wastegate line which will damp out pressure fluctuations and any pulsing.
 
I've got the same turbocharger on my 1hdft. I experienced the same fluctuations like you have. However i have a mamba wastegate actuator. I thought using that would help setting boost better than an mbc. I was wrong, it caused those weird fluctuations. I ended up shimming it and using an mbc... that fixed the fluctuations, but i still have trouble keeping boost into higher rpms.
I have boost set at 20 psi, but when it get's there it drops back to 16 or 17 and stays there. I need to dig into that, but life and work get's in the way. It's only been three years like this.:doh:

I'm not sure if this helps you anything tho.
 
Interesting, so some combination of your shimming your aftermarket waste gate and MBC fixed your fluctuations (not withstanding your initial spike).

What MBC are you running?

I did notice the same spike as you when I upped my boost pressure to 19 (I've only been running 15psi). My first thoughts were that it takes a moment for the wastegate to respond, so it may pass the threshold momentarily before the waste gate "catches up" to release the extra pressure. But I'm no expert. If I can eliminate the fluctuations, I could live with the short spike.

Thanks for chiming in (its been 3 years for me too lol)

PS: have you felt comfortable running at 20psi? I remained at 15 given the stock turbine/journal bearings, although I did install a 360 thrust bearing when reassembling. Wasn't sure what the weak link in the stock Ct26 setup is when pushing past 15.
 
gerg said:
Wher are you sourcing your pressure and how much tubing is between the reference source and the wastegate actuator?
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Source is from the compressor housing. I'd say there is about 12" from housing to MBC, and the same on the return trip to the wastegate.

I changed the spring tonight for the stiffer version and dialed it in to about 16psi. Unfortunately still have same issue.

Low Rpm/speeds totally fine. Only a problem if I really push it hard. It's really mostly noticeable at highway speeds particularly maintaining speed uphill.
 
If it's like a positive feedback loop you need a dampener in the line to dampen it like Dougal said. If you put a shot of grease in the line it still allows the pressure to move through the line but acts like a cushion. I dunno, I'm guessing a bit but what about adding a rediculously long section of line to screw with what ever balance the phenomenon is creating? I think this might be akin to death wobble in a steering system.
g
 
I have had zero surge with my set up in 20,000kms. I am running 20psi with mbc. . I have also towed a boler trailer on a 2500km road trip through the mountians of BC, montana and idaho without any issues.
 
Malahki said:
I have had zero surge with my set up in 20,000kms. I am running 20psi with mbc. . I have also towed a boler trailer on a 2500km road trip through the mountians of BC, montana and idaho without any issues.
Click to expand...

Thanks for chiming in, did you retain the stock waste gate? What MBC did you use?
 
tweeek said:
Interesting, so some combination of your shimming your aftermarket waste gate and MBC fixed your fluctuations (not withstanding your initial spike).

What MBC are you running?

I did notice the same spike as you when I upped my boost pressure to 19 (I've only been running 15psi). My first thoughts were that it takes a moment for the wastegate to respond, so it may pass the threshold momentarily before the waste gate "catches up" to release the extra pressure. But I'm no expert. If I can eliminate the fluctuations, I could live with the short spike.

Thanks for chiming in (its been 3 years for me too lol)

PS: have you felt comfortable running at 20psi? I remained at 15 given the stock turbine/journal bearings, although I did install a 360 thrust bearing when reassembling. Wasn't sure what the weak link in the stock Ct26 setup is when pushing past 15.
Click to expand...


I have a cheap ebay mbc. I had it on my 12ht for years without issues. However on the 12ht i could use a very short hose from the turbo to the wastegate actuator. On the 1hdft i had to use use a much longer hose due to the positioning of the turbo. The spike could very well be caused by ballooning of the hose. Never thought of that...

About the max boost. I believe the 360 degree thrust washer will strengten it enough to run up to 25psi. This is all internet knowlage, so don't quote me on this 😉
 
Dougal said:
3000rpm changes the diagnosis a bit.

I would fit a restrictor in the wastegate line which will damp out pressure fluctuations and any pulsing.
Click to expand...
gerg said:
If it's like a positive feedback loop you need a dampener in the line to dampen it like Dougal said.
Click to expand...

Per your advice, I simply added worm gear clamps to the waste gate lines and cinced them down to add restriction.

Pinching the line between the MBC and waste gate definitely changes the characteristics of my fluctuations. I have to tighten it to the point the waste gate won't open, then back off in very small increments. I can get it to the point it fluctuates a few times then levels out at desired PSI, or large 4-5psi boost spike, before levelling out. Its not perfect but an improvement.

So your theory definitely holds ground, any ideas WHY this would be, and what a more permanent solution would be?

I ordered a new MBC, the same as Malahki, since he isn't having issues just to rule out MBC.
 
tweeek said:
Per your advice, I simply added worm gear clamps to the waste gate lines and cinced them down to add restriction.

Pinching the line between the MBC and waste gate definitely changes the characteristics of my fluctuations. I have to tighten it to the point the waste gate won't open, then back off in very small increments. I can get it to the point it fluctuates a few times then levels out at desired PSI, or large 4-5psi boost spike, before levelling out. Its not perfect but an improvement.

So your theory definitely holds ground, any ideas WHY this would be, and what a more permanent solution would be?

I ordered a new MBC, the same as Malahki, since he isn't having issues just to rule out MBC.
Click to expand...

Maybe you're using hose between the turbo and MBC that is too soft and expands under pressure? The stuff I'm using is almost too small for the turbo end fittings, you really need to work it on over the nipple. Also, use zipties on the connections so they don't slip or leak.
 
IanB said:
Maybe you're using hose between the turbo and MBC that is too soft and expands under pressure? The stuff I'm using is almost too small for the turbo end fittings, you really need to work it on over the nipple. Also, use zipties on the connections so they don't slip or leak.
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I thought of that too, I was originally using 6mm 50psi fuel line. I removed that and installed reinforced silicon hoses yesterday as well. No change before installing hose clamp though :( I do think the 1/4 hose may be to large though given yesterday's findings. I guess that's the next thing to try. Unfortunately the MBC I ordered has 1/4 fittings
 
I've never dealt with this myself but at least you've got an idea on what's happening.
image.webp
 
Stephan Mester said:
I will use that Maba 11-12 Tdo5 also.
Just have to get a few things finished before

View attachment 1950712

View attachment 1950713

View attachment 1950714
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I think you will be happy with the Mamba. The 12 blade wheel is definitely a better choice than the 9 blade. The injector pump on my 1HDt recieved a slightly stiffer aneroid spring when it was rebuilt to suit the extra boost. I have been running 24psi at the manifold. My motor has some mild porting and a a multi angle valve job. I posted some notes from the install here on mud. In this thread at around #863.
You may also want to find the other half of you wagon. Looks good. How I wish I could tig weld.
 
Last edited:
Hi, thanks for the hint about the stiffer spring.
(will have a look on the build in too)
Tig welding isnt that complicated, ecept you go for the thin stuff.
Start with arc / stick welding (get proper rods, ESAB or SUPERON) and do some practise.
When youre good in stick welding, grab yourself a guy who can Tig weld and let him show you.
I learn it from a pensioneer who wleded his whole live on oild rigs and vessels, making pipes for dairy aso.
cheers
Stephan
 
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