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HX-35 holset

The first Banks Sidewinder kits for the GM 6.2 & IH/Ford 6.9 & 7.3 IDI's used a non-wastegated T3/T4 hybrid sourced from either Rotomaster or Switzer. It was a TO4B25. The Banks logo was cast on the side of the turbine housing. A/R was around 1.0. Might well have been a proprietary turbine housing as there aren't many T3 flanged turbines with an A/R (1.0) that loose.

Later, when Banks went to wastegated turbo's on these kits, the Humvee 6.2 kits & IH 6.9/7.3 kits I've seen were Mistu TE06H-25C turbos.

The Banks/Mitsu turbos were expensive. Genuine Mitsu components are pretty expensive, unless bought in very large lots.
 
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I saw a banks sytem on a 80's chevy the manifold is a better design than the 6.5 one,but I wasnt sure about the turbo he said it was making about 10 psi.The compressor side of the hx35 is capable of more air flow than most 6.5s need, the problem is the turbine side exhaust flow.
 
I saw a banks sytem on a 80's chevy the manifold is a better design than the 6.5 one,but I wasnt sure about the turbo he said it was making about 10 psi.The compressor side of the hx35 is capable of more air flow than most 6.5s need, the problem is the turbine side exhaust flow.

Yep. And this experience is well aligned w/ how Holset respresents the HX-35.

For engine capacity (L): 5.0 - 6.5
Output Range (hp): 100-280
Airflow (kg/s): 0.46

That range of 100-280 hp is a reflection of where the HX-35 will be most effective. For a higher hp 6.5 goal, it's a little small.

While the turbo companies do size the overall turbine flow porportionally to the compressor, wastegated turbos will usually have a little smaller turbine wheel exducer diameter. Some (but not all - the wheel is still smaller) of this proportionally greater turbine restriction can be made up for w/ exh bypass flow thru the wastegate.

As is logical, this is done to make it spool a little earlier, so the turbo is more effective earlier in the rpm range. For that, you trade some overall turbine flow capacity. The VGT turbo's get a little more wiggle room because they can vary the nozzle/volute area - but they're still gonna tend to have a somewhat smaller turbine wheel.
 
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BTW - I'm not particularly passionate about any brand. I am a big fan of a wide selection of turbo components. That are widely available & can be applied w/ a little work & smarts to perform quite effectively. Because they're widely available, the parts can be scrounged at very good prices.

The trick is digging at understanding the components & how they might work together in your given application, before you go hunting & bolt something on.
 
The VGT should be great because you can adjust it ,instead of mixing and and matching and lots of trial and error.
 
If the standalone VGT controller becomes a reality & works well, it could make for a turbo that is uniquely effective across the mass airflow/hp range.

The compressor can provide well into the 60's lbs/min airflow, while remaining well inside it's 70% efficiency island. So plenty big. Drive pressure will have to be measured to know. We know the turbine can flow adequately for the 6.7 Cummins to make it's 350 hp spec.
 
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Didn't ChicagoTDP run a Holset HX?....been running that way for quite some time iirc....

Thank you - been waiting for another old-timer (bet you don't get called THAT too often, Chris!) to remember...

Yes, other people have experimented with different turbos on our beloved 6.5 before. The following 2 either had HX or HY holsets - can't remember, but they were the same turbo...

-- ChicagoTDP ran a Penninsular 18:1 with a Holset HX and custom built all the flanging for it. He also built a hanging ATA because of the very high IATs.

--CanadianRigger also ran a similar setup, but with a stock compression engine, custom tuning and IP by Lyndon at Westers (advantage to being an Alberta boy). He and Chicago used to post videos of their escapades, and both trucks were VERY hot!!! CR's truck went boom, though, and never quite got all rebuilt... Russell was busy designing and trying to find ways to make the 6.5 strong enough to handle that much boost and fuel, but circumstances put a hold on things.

So ... Can a Holset work on a 6.5? Obviously. Needs Intercooler or WMI, higher boost cries out for lowered compression, drive pressures are a factor as yet unquantified, but suggest a need for increased fueling. Other issues include lack of bolt-on-ability, need for thoughts of controlling boost limits, etc. Moving to experimenting with a VVT is a seriously cool idea, but thoughts need to go to control mechanisms... are there benefits to doing so? Also Obviously.

We have a whole pile of people putting ATTs on their trucks, and so far, I haven't heard anything negative back. The envelope is just STARTING to get explored (with what else can be done - reference Buddy and his additions of alt. fuels, custom timing, etc ... KOJO is working with members to see about custom fueling curves, and Bill Heath is thinking this all through with an eye on creating custom chips; maybe a GL-ATT is in the future.)

So ... Does the ATT work on a 6.5? Obviously. Benefits include better airflow, lower IATs/EGTs (elimination of need for Intercooling or WMI), works as a bolt-on with stock compression in most 'normal' circumstances - towing, daily driving. Lowered drive pressure = greater efficiency = MPG increase; savings can pay for the purchase. Most of us can put on our own ATT - no special tools or expertise needed; it's basically a bolt-on kit ... are there benefits to going with an ATT? Also Obviously.

Which one is best?

THAT depends on what you want. If you're looking to lay down a block's worth of tire-tread, build one like RonnieJoe did, aimed at doing that (he uses another DIFFERENT turbo, BTW), or go Penninsular (like ChicagoTDP) or build your own 18:1, as Darrin or Slim have done. Add Nitrous, Propane, custom fueling tables (like Buddy is working on), ... there are lots of things that can work. Not all of those variables have been explored with the ATT yet, either. Bill Heath went to true duals and twins, something CIL6 is working on, also. Maybe THEY have the right way to do this... I dunno.

For Joe Average guy, (like Leo, or OHT, or Al, or a host of others on here), bolting on an ATT is all the change they need or want, they can do it with no special stuff, and they get everything they need from it. Tomorrow. They don't need to know about Turbine maps, about flow dynamics, about the complex interplays of pressure/temperature/volume... they bolt it on and it works. If there was such a kit available for the Holset, they'd look at it, too, and then it would come down to more specific characteristics, and be influenced by advertising, truths/lies bought and sold, reputations and rumours, and he-said / she-said campaigns, like everything else in the marketplace. I offer our colective experience with the 'Chip Wars' as a graphic example...

For now, that isn't the case, as there is no other bolt-on upgrade to the GM-X, but that certainly doesn't make this topic any less valid... the point is, THERE WILL BE, eventually.

This topic is worth discussing. This is worth experimenting with. This is the fringe edge of innovation, and everybody brings something to the table to help make it all work... sometimes, the theory gets pushed aside by the practical (ie: things really CAN go faster than the sound barrier without disintegrating), and sometimes, the theory provides clear guidance about why something is just a bad idea in practice.

The expertise, knowledge, and experience that different people bring to the table helps to make this community grow and makes ideas flourish...

As the Apple commercial in the early 80's said,

http://www.youtube.com/watch?v=gE857DJWX2w
 
As what should be a sidenote in a thread entitled "Holset HX-35", I've also experimented a fair bit w/ Mitsubishi (MHI) turbos. If anyone is looking for info on them, feel free to ask. I may have it, or know someone that does.

The high cost of experimenting w/ genuine Mitsubishi turbo components has limited how much turbo enthusiasts have played with them.

On the Mitsu turbo projects, I interacted quite a bit w/ their prime US distributor at the time.
 
Have you gotten an further on your examination of VVTech, SmithvilleD? It seems that there is a lot of potential in that area, if somebody can figure out how to adapt new technology to old trucks... that thought is quite exciting...
 
I recently put a few details in the VGT Turbo for Christmas thread that I learned from Brayden at Fleece Performance.

They're the ones making good progress on a standalone controller. They've got couple trucks running around testing/developing their product. Believe they've got a guy testing a controller to vary the VGT on a Ford as well.

Not to promote Forum disloyalty ( :smile5: ), but the Competition Diesel forum seems to get the most discussion on VGT control mechs. Also a good deal of comparison info for many turbo's.
 
As this is an HX-35 thread, a brief summary of some of the things necessary is prolly in order.

The HX-35 uses turbines flanged in T3, like the 6.5, so no adaptation needed there. Bolts right up. I would suggest some type of brace back to the engine, like the stock setup. Regardless of which turbo you employ, it's a big, heavy chunk, hanging out on an exh manifold that is also a relatively long lever arm. A brace would be simple insurance against engine vibration ever setting up vibration & any associated metal fatigue in the exh manifold.

Oil feed needs an adaptor from the Holset's M12 x 1.5 pitch, to utilize the stock 6.5 ss oil feed line. Midniteplowboyy & others have sourced this fitting, so it's out there.

The fabrication stuff is the downpipe, & fitting an air filter/air intake to the larger OD of the HX-35's compressor inlet. Custom flanges for the common HX-35 turbines are readily available. They've typically got a 3" hole designed to slip fit in your 3", tight 90 bend & weld. Chicago TDP, Midnite, etc., have pretty good pics of what they did in the albums on the 6.5 forums.

The final key is understanding & respecting how much boost your 6.5 can handle. And then making sure you do what it takes to keep boost levels under control. The HX-35 doesn't have to make too much boost (or the accompanying high comp outlet temps that follow), but it absolutely can & will if adequate boost control methods aren't used.

Stock fueling levels seem to generate drive energy amts the internal wastegate & passages can deal w/ when you get the right actuator setup. As you throw more fuel & hence drive energy at it, there will come a point where there's not enough exh bypass flow capacity to keep things in check.

This is consistent w/ Holset's contention that 280 hp is about the max that's reasonably efficient to try do w/ this turbo. Numerous 5.9 guys have gone past 300 hp - that's just heading past what this turbo is best at - which will be that 100 hp to 280 hp range that Holset suggests.
 
Yes a Variant of TDO7-22A, ATT has slightly different compessor, and slightly improved spool up over the TDO-7

quote=Smithville,
As what should be a sidenote in a thread entitled "Holset HX-35", I've also experimented a fair bit w/ Mitsubishi (MHI) turbos. If anyone is looking for info on them, feel free to ask. I may have it, or know someone that does.

The high cost of experimenting w/ genuine Mitsubishi turbo components has limited how much turbo enthusiasts have played with them.

On the Mitsu turbo projects, I interacted quite a bit w/ their prime US distributor at the time.



This will be interesting
 
Because this is a thread entitled "HX-35" I'll keep my response brief.

This link is a summary of Bill Hahn Jr.'s turbo experience. He's got a good deal of turbo knowledge in general. And a good deal specifically related to MHI turbos.

http://www.turbosystem.com/cycle/Billjr/index.htm

Been a few years ago, but I've dealt w/ & spoken w/ Bill a fair bit. When I dealt w/ him, they'd spent the time/training/$'s to become one of a very short list of MHI US authorized distributors.

Also note I provided a bit more specific info regarding the MHI turbos in the Banks kits. My information didn't come from a magazine article. And the later kits were wastegated. Banks sells in CA. Gotta have CARB approval there. Couldn't have continued selling a non-'gated turbo as that setup couldn't meet emissions regs. I really do have some experience w/ turbochargers.
 
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I run the WH1C, which is basically the same as the first generation HX35, just with a V-banded compressor housing. Running 0.010" thicker head gaskets, studs, an IC, marine injectors, 4911 pump cranked all the way and 15psi(creeps up to around 18 sometimes) boost.

So far she's still running, 30k miles on that setup, original short block, 225k total miles. It seams a pretty good match for the 6.5 with available fuel, EGT's, coolant and boost max out at the same time(mainly coolant temp). I've hit the limit my HO water pump can flow, not much use in a four plunger marine pump until I can figure out how to get more water flow through the heads.

ChicagoTDP has ran alot of the older holsets, H1C, WH1C, HY35 and both versions of the HX35, IIRC, on his 18:1 Penn engine. Seams like the HY35 might have giving him better fuel mileage, but he liked the power of the HX35 better.
 
Asked my turbo engineer friend about a good way to relate the degree of impact engine displacement has on turbocharger turbine drive energy.

He suggested simply comparing naturally aspirated airflow's of the 2 engines. He said, beyond those differences, remaining differences in drive energy are pretty much fuel rate = heat energy differences. The concept is independent of any specific turbocharger.

As relates to the HX-35 on either the Cummins or GM diesel engines:

Cummins - 5.9L = ~ 354ci
GM - 6.5L = ~ 395ci

Does anybody have GM-x turbo's out & can easily measure the turbine wheel exducer diameters for comparison? The turbine housing's exducer bore around the wheel is typically 1-2 mm bigger & that diameter gives some indication of it's flow potential.

I've found references that the earlier GM-3 turbine wheel exducer was 2.150 " = ~ 54.6 mm
GM-8 turbine wheel exducer was 2.030 " = ~ 51.6 mm

As the GM-8 is often suggested to flow better on both comp & turbine sides, it seems logical the turbine side difference is in the later turbo's different wastegate/exhaust elbow configuration.

For turbine wheel exducer size comparison, the HX-35's wheel is 60 mm = rated range 100 - 280 hp
The HX-40 is 64 mm = rated range of 175 - 350 hp

While this is thread was started on the Holset HX-35, the general relationships btwn wheel sizing & turbine flow are good to understand. Individual turbine wheel designs make compromises regarding efficiency (how much drive energy it can turn into shaft power) & turbine flow potential. Energy extracted & flow restriction are generally directly related. More energy extracted, more restriction. Less, less., etc. As materials & wheel design improves, they're nibbling away at that tradeoff.
 

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  • Naturally aspirated airflow - vs - engine displacement.pdf
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GM-8
Compressor Wheel: Inducer = 1.962" Exducer = 2.695"
Turbine Wheel: Inducer = 2.423" Exducer = 2.010"
 
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