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All I got for Christmas was a VGT turbo

Darrin is your turbo electric or pneumatic actuation,and did I read that right,they can be water cooled
 
The turbo I'm working w/ has the electric actuator. Holset calls the specific one on this turbo "Type 2B Electric Actuator." The cutaway pic on the Holset link just previous in this thread shows the pneumatic actuator. I've seen the pneumatic actuator on the larger HE431ve turbo, but don't know if would be a bolt up to my HE351ve.

The center section is plumbed & has engine coolant passages that put coolant into/thru a cavity in the electric actuator's aluminum body. You can see the sealed cavity in the actuator pic at the beginning of this thread. The actuator body houses the electric motor, gear reductions, & a circuit/processor board. Would think the engine coolant thru that cavity in the actuator body is to keep the temps inside the actuator limited enough to not toast the electronic circuit board & motor. Coolant should also limit any oil coking in the bearings upon engine shutdown.

Larry, do you know any dealer techs that would be working on the Cummins 6.7's routinely? I've read some opinions that think the turbo VGT mech gumming up from carbon problem relates to quite a bit of EGR flow & trucks that set idling more than the average truck. Would be good to hear from a tech that see's the 6.7 trucks come in w/ the issue & if there are any tech bulletin/updates. I think those trucks electronics log a fair bit of VGT motion history, so they might have some individual engine history to see if there's any correlation to excessive idle times, too much EGR, etc.
 
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There is more programming in the 6.5 PCM than just the target boost. For commanding PWM duty cycle for the wastegate control. I think PWM control would be the best solution. Might even be able to use other programming like the EGR PWM duty cycle which may have more controls and the DTCs disabled.
 
You were mentioning an IC as kind of a shrapnel trap... you may also want to get someone's old MAF sensor from an S truck, the honeycomb screen in that flowed quite well and saved my truck when it was pre turbo, it may work post turbo as well.
 
The plan is to have a MAS pre-turbo (at least temporarily) to get some actual readings, so I actually know what the mass airflow is under different conditions. For that purpose, they're typically mounted pre-turbo & I believe they need to be at least a certain distance from the compressor inlet, to avoid screwy air/turbulence issues (created by the compressor) impacting how accurately the MAS meters the airflow.

That being said, I've spoken to a couple people I believe to be knowledgable in fluid dynamics that say this TAG (turbo air guide) device has some merit.

http://www.dieselpowerproducts.net/tag

They're divided on whether or not the benefit is worth the cost, but they seem to think it would be of some benefit. Anybody else on the forum have any knowledge of this type of device being used at the compressor inlet. TD maybe?

Also would be interested to hear if anybody has come across that honeycomb material in another application where a guy might be able to get the material itself cheaper?
 
most industrail water pumps have something like that,usely just two flat iron plates too straiten the fluid flow
 
seems it would be better to spiral the air into the compressor than direct it straight at it...

some contradicting info on their site tho especially concerning the 60 series detriot.
 
seems it would be better to spiral the air into the compressor than direct it straight at it...

some contradicting info on their site tho especially concerning the 60 series detriot.

That's kinda why I'd like to try & find a chunk of that material big enough to make my own & see how it works, w/o the $100-200 cost to find out if it really works.

I've got some smaller chunks of the honey comb from past project's MAS modifications, but nother near big enough to fit the VGT Holset's compressor inlet. Also guess one would want to be pretty confident whatever you rigged up couldn't get loose & sucked into the compressor.

Couple of the pics look like the stock Dodge air tube comes w/ some type of air deflectors/directors, but don't know if their intent was performance improvement, or noise/whistle control.
 
I've got some smaller chunks of the honey comb from past project's MAS modifications, but nother near big enough to fit the VGT Holset's compressor inlet. Also guess one would want to be pretty confident whatever you rigged up couldn't get loose & sucked into the compressor.

Would the comb out of an old soot trap work? Do you still have your old one?
 
Do still have the truck's soot trap. Been a while since I've looked closely at that matrix.

Off-hand, I thought they were some sort of ceramic material that had the platinum/paladium (whatever the heavy metal catalysts are) adsorbed onto the surface.

Having observed "others" rodding/breaking out that material in the early days of catcons, when there weren't high performance alternative cats that actually flowed reasonably, I recall the material breaking apart like a ceramic.

A number of import car's MAS have what looks very similar to the honey comb metal shown in the turbo air guide pics. My thought in finding a metal honeycomb material is that I'm more inclined to trust a brazed in metal part not separating, so less potential to get loose & into the compressor.

I agree w/ being cautiously skeptical as the OTR Detroit 60 series testimonial seemed not well aligned with other testimonials on the site. Just thought the concept was interesting enough to mention & maybe trying to figure out how to DIY/replicate something like it to see for myself.
 
That being said, I've spoken to a couple people I believe to be knowledgable in fluid dynamics that say this TAG (turbo air guide) device has some merit.

http://www.dieselpowerproducts.net/tag

They're divided on whether or not the benefit is worth the cost, but they seem to think it would be of some benefit. Anybody else on the forum have any knowledge of this type of device being used at the compressor inlet. TD maybe?

Also would be interested to hear if anybody has come across that honeycomb material in another application where a guy might be able to get the material itself cheaper?

Just saw this interesting,,,,we used to use some flow straighteners on large gas turbines, but that was on a 10' x 8' intake duct on a 60,000 shp gas turbine, to correct a negative pressure boundary that was putting a high vs low pressure wave into 1st stages of compression in an axial flow turbine, loading & unloading blades in the rotor slots causing cyclic fatigue I'm not sure zactly how this would work on a centrifugal compressor that is a one piece casting.

As for honeycomb you could try the MAF sensor from a 97/98 S 6.5 might replicate what they are trying to accomplish, this sort of looks to me like that Tornado flow straightener that was on late nite TV few years back, I don't see it doing much myself, new stuff happens all time but I'd think if viable this one would have been "discovered" before now.

I'll run this by some guys up in our turbo design group at work to get their opinions on it, but we are dealing with something that flows more than the Holset does when dealing with 4400 & 6000 Shp locomotive Diesels :D
 
Just saw this interesting,,,,we used to use some flow straighteners on large gas turbines, but that was on a 10' x 8' intake duct on a 60,000 shp gas turbine, to correct a negative pressure boundary that was putting a high vs low pressure wave into 1st stages of compression in an axial flow turbine, loading & unloading blades in the rotor slots causing cyclic fatigue I'm not sure zactly how this would work on a centrifugal compressor that is a one piece casting.

As for honeycomb you could try the MAF sensor from a 97/98 S 6.5 might replicate what they are trying to accomplish, this sort of looks to me like that Tornado flow straightener that was on late nite TV few years back, I don't see it doing much myself, new stuff happens all time but I'd think if viable this one would have been "discovered" before now.

I'll run this by some guys up in our turbo design group at work to get their opinions on it, but we are dealing with something that flows more than the Holset does when dealing with 4400 & 6000 Shp locomotive Diesels :D

One of my way too many hobbies is riding motocross bikes. A great upgrade to even the latest and greatest new bikes is a vortex in the intake. They really help with bottom end, and I like 250cc 2 strokes, they need help on the bottom.
 
A turbocharger design engineer buddy said it's not at all a new discovery as the theory was put forth long ago. His take was that any efficiency gain probably comes from equalizing the loading across all the compressor blades, all around their rotational path. Blade loading is typically even when the inlet plumbing has a significant length straight section in front of it. But can be a factor when there's a bend in the plumbing close to the inlet. (occurs to me there are bends plenty close to the comp inlet on most 6.5 setups - maybe moving a battery to allow a straigher path is worthwhile?)

They CFD model this type of thing, but he said the basic understanding is since air has mass, that mass in motion has inertia that resists changing direction. So it tends to pile up, or increase density on the outside of the bend where forced to change direction.

While my friend doesn't work for Holset, he suggested the air guides in the stock Dodge/Cummins inlet tube feeding the compressor were likely an engineered solution resulting either from CFD modeling, or actual measurement of flow at the compressor inlet.

I gather if this honeycomb/air straightener/air guide improves efficiency, it does this from the physics relationship of flow velocity & pressure. Obviously I can't CFD model anything, but would expect any worthwhile efficiency improvement might show in turbine drive pressure to boost ratio.
 
Sounds plausable, I see similar disparity with the elbow on the S truck turbo inlet vs the more radiused one used in the F truck, on hard acceleration with my GM-8 with S turbo inlet tube I would often set the air DP air filter "pop up" monitor, swapping to a F inlet tube I would not set it, which was sort of an indication to me the turbo was having to pull harder to pull air. Straigtening out the intake tube could be a plus, with my ATT I've not set it, but I had the IC on it then also so that may have been a factor.

too many variables and not enough test instrumentation :mad2:
 
Just saw a post from Braden at Fleece Performance saying w/ their controller allowing the HE351ve turbine to run at more opened up VGT settings, they're seeing 45 psi boost w/ drive pressures around 50 psi w/ a stock HE351ve.

It appears the stock 6.7 VGT control logic often maintains high drive pressures to get the EGR flow needed for emissions compliance.
 
I just got a msg back from Brayden at Fleece Performance. He says they're about 75% complete on having the product ready for market.

They have two trucks running this turbo standalone w/ their module controlling the VGT.

It sounds like they're trying 2 different approaches. One is running CAN (controller area network) inputs & the other using analog inputs (MAP, CPS(rpm), TPS, etc.)

The analog will be released a bit later due to some additional circuitry necessary to utilize additional inputs like drive pressure, shaft speed, etc.

They expect the pricing for such a controller to be sub $500. Not really comparable to the wastegate actuator methods some are using. But, I suspect an electronic control scheme that can utilize all those inputs offers some valuable advantages in both tunability & safeguarding the turbo if any VGT mech sticking ever happens.
 
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so along with turbo and standalone controller we also need to buy sensors and misc parts for controller to read or does that come with it
 
As their product isn't launched yet, can't really say w/ certainty what it will/won't include. My understanding is it will be able to communicate w/ a laptop via USB cable. Saw mention of Fleece actually being able to connect via the 'Net to your laptop & adjust parameters in the controller's tables. Can't confirm this as I've just communicated w/ Braden @ FP to get a few details, not pestering him too much on details until it's ready to launch.

In my '95 6.5 truck's case, it already has the MAP, CPS, & TPS sensors.

The HE351ve turbo's came w/ a shaftspeed sensor.

We would have to come up w/ whatever their controller will use for turbine drive pressure. I'm not certain what they're using? I've seen the common GM 3 bar MAP sensors used to datalog drive pressure as long as it's well enough isolated from exh heat (often isolated w/ copper pressure gauge line coiled to shed heat, filtered w/ something like sintered iron or fine steel wool, then adapted/joined to the black nylon line). I don't have a lot of experience measuring/logging drive pressure. On the performance car turbo projects I've done, drive pressure was relevant, but not as critical because the car's never ran peak boost pressures for > maybe 1 minute.

They may be using some other OEM application's drive pressure sensor. 3 bar is ~ 43 psi. While I'd hope this turbo will perform as I need on my 6.5 w/o drive pressures anywhere near 43 psi, some other applications may go higher. If anybody has other suggestions on a cost-effective sensor, please post in this thread.

Currently, my preference would be to use the GM 3 bar MAP's if possible, simply because they're used widely & I can probably source several sensors from a salvage yard inexpensively. My plan would be to also incorporate an IAT sensor both pre-IC & the stock IAT sensor. Ideally would use the same sensor both 'cause can prolly find them low-cost from the salvage yard, & using the same air temp sensors would mean same signal/calibration for easier datalogging setup.
 
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