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HX-35 holset

On the ricer's car, the blow off valve is used to save the compresser wheel
blades when the throttle valve is closed between shiftes and the end of a run.
When the throttle valve is closed there is a huge surge of air backing up the intake!

thay also run a bigger wastegate.... I got a hx35 going on my 2.3 4cylinder I will be using a 38mm exturnal wastegate that is mouted pre turbo in the header, I have the block off plate the seal up the internal wastegate
 
If you have an hy I would try it first, should still be better than stock and the wastegate will flow more, that guy had a cummins ,you cant compare to what works for him, of course you can do what ever you want.
 
Whole lot of modifications needed , a turbo designed for a 5.9 liter on 6.5 liter engine, More chance for error, not my place to say what is good or bad, I don;t like to gamble with my money, gets expensive to replace a 6.5 block. The whole reason I made the ATT was for durability towing, it will do almost anything you ask of it, more fuel than we can get now will give you more boost.

I don't like using small turbine housings for low end spool up. The 6.5 and 6.2 both have enough power from 600 rpm to 1400 / 1500 rpm to get anything moving you could possibly want to haul. If your into zero to sixty times have at it, that is a totally different venue. The 6.5 will not tolerate a lot of boost at low rpm Called lugging and it is the best way to do your block in. My brother is a mechanical engineer for a large space agency and he has a lot of resources that I was fortunate to be able to make use of. Theory is great but reality is better. Just my two cents,
 
I agree with low end power causing a problem, but it is harder to build for top end fueling,but alot easier on the motor, I would like my peak to be at 3000 rpm or higher instead of 2500 and lower. Another problem is lower compression totally killed all my low end, its all a compromise, especially if its a daily driver or tow vehicle. My truck is being built for pulling so that is no concern.
 
So when we're discussing blow-off valves as a boost control method, we're talking theory, or experience/reality?

The presumption the HX-35 was designed exclusively for the 5.9 Cummins is simply untrue. It's certainly used in other applications.

Many of my ideas regarding turbochargers come from actual experience trying non-stock, alternative chargers. Bolted my first non-stock M&W turbo on a tractor engine ~ 26 years ago.

One of many knowledgeable turbo experts that keep me honest in my understanding of turbos is also a mechanical design engineer I've know since college. He doesn't work at a space agency. He works at Garrett, has for 20 years - they've designed & built a few turbos over the years - and the majority were designed for internal combustion engines.

My point in these discussions in NOT to create or participate in arguments. It's to put valid information out there to aid other turbo experimenters. It's fine to hold personal opinions. I would suggest for consideration, that the holding of such opinions is highly correlated to the number of tested & true 6.5 turbocharger alternatives currently available to the 6.5 enthusiast community.

The 5.9 Cummins, 6.6 Duramax, & Powerstroke enthusiasts have a multitude of turbo options. Check out their forums. Competition Diesel is a good, cross-brand forum example. Read their turbo discussions. The depth of legitimate turbo understanding - from theory to implementation, is simply on a different level as compared to our 6.5 forums.

Our 6.2/6.5 foundation has been around in turbocharged format for 18 years.

How many turbo options have been explored? How many popular options are currently available as an easy bolt-on? The answers to these questions are quite solidly linked to one another.
 
A blow of valve is for gas motors , so the turbo don't chirp and possibly snap the shaft, when the throttle plate is closed under full boost, so far I have ran a gm1,wh1c,and pro 52,on my 6.2 the 6.5 needs a custom built charger/ hybrid if you want it to perfect, all the rest will have sort of compromise.
 
So when we're discussing blow-off valves as a boost control method, we're talking theory, or experience/reality?

The presumption the HX-35 was designed exclusively for the 5.9 Cummins is simply untrue. It's certainly used in other applications.

Many of my ideas regarding turbochargers come from actual experience trying non-stock, alternative chargers. Bolted my first non-stock M&W turbo on a tractor engine ~ 26 years ago.

One of many knowledgeable turbo experts that keep me honest in my understanding of turbos is also a mechanical design engineer I've know since college. He doesn't work at a space agency. He works at Garrett, has for 20 years - they've designed & built a few turbos over the years - and the majority were designed for internal combustion engines.

My point in these discussions in NOT to create or participate in arguments. It's to put valid information out there to aid other turbo experimenters. It's fine to hold personal opinions. I would suggest for consideration, that the holding of such opinions is highly correlated to the number of tested & true 6.5 turbocharger alternatives currently available to the 6.5 enthusiast community.

The 5.9 Cummins, 6.6 Duramax, & Powerstroke enthusiasts have a multitude of turbo options. Check out their forums. Competition Diesel is a good, cross-brand forum example. Read their turbo discussions. The depth of legitimate turbo understanding - from theory to implementation, is simply on a different level as compared to our 6.5 forums.

Our 6.2/6.5 foundation has been around in turbocharged format for 18 years.

How many turbo options have been explored? How many popular options are currently available as an easy bolt-on? The answers to these questions are quite solidly linked to one another.


I have experience with blow off vales, and I don't comment on things that I have no experience with. After 30 years of working on all types of power plants / turbo charged blowers roots, screw types and alternative fuels, did electronics and electronic fuel controls since they first came out. Not trying to say not to experiment that is the way things get done.

My brother and I don't see eye to eye on a lot of things (and we have big arguments at times) but I respect his opinion and technical expertise. We do agree that calculations can not take into account some of the variables that arise in real life. The calculations are only complete when everything that can affect the outcome has been included, guess that is why engineers build then test to see if the calculations are correct.

With any thing there are individuals that have never been to school for their particular field of expertise and yet they are excellent at what they do because they have an innate natural ability for including fuzzy data that is not generally included in the math.

The presumption that the holset hx35 is used only on Cummings engine was an opinion formulated by the reader, I merely stated that a turbo used on a 5.9 liter motor has been given more drive energy by placing it on a larger displacement motor, changes the drive characteristics and the end results.

All of the information formulated or speculated so far has been related or surmised from that platform,Hence the assumption on my part that the turbo is used and the data relayed is based on the 5,9 Cummings motor, Unless I missed the reference to another power plant other than the Cummings.

I also researched construction equipment (worked on them also) they have a constant rpm for their working range however the cyclical loading and unloading creates fluctuations in rpm and the turbo must stay constant or stable or you get engine surging. The turbos have certain innate characteristics which make their turbo design different, and interesting. SO without making anyone mad I do have an opinion based in fact.

No one person is an expert or knows all things, I have a lot to learn but I also have a little innate and learned ability for being able to intuitively gather the big picture before jumping into something.

This is just my opinion, I try not to squelch others ideas by insinuating I have any more knowledge than they do. That would make me arrogant and ignorant. Two things I despise. Also look at my member number and the amount of posts I have, should show that I don't post alot just when I think I have something say that may be relevant to the discussion.
 
Sorry if I offended any one , Im sure the ATT is a great turbo, you can run a blow off valve on a diesel, but I never will, the reason everybody uses the 5.9 to compare the hx35 ,especially with the wastegated 12cm housing is because we never seen it on any thing else, so who is to blame?
 
I agree with low end power causing a problem, but it is harder to build for top end fueling,but alot easier on the motor, I would like my peak to be at 3000 rpm or higher instead of 2500 and lower. Another problem is lower compression totally killed all my low end, its all a compromise, especially if its a daily driver or tow vehicle. My truck is being built for pulling so that is no concern.

Lower compression makes a engine a nutless wonder at low rpms?
 
Sorry if I offended any one , Im sure the ATT is a great turbo, you can run a blow off valve on a diesel, but I never will, the reason everybody uses the 5.9 to compare the hx35 ,especially with the wastegated 12cm housing is because we never seen it on any thing else, so who is to blame?


Heck no I am not offended at all, and if it came across that way then I apologize. I was just answering the questions posed regarding my knowledge of the subject matter, I have much thicker skin than that, healthy discussion is a good thing, we don't have to agree at all. That makes this site interesting, we can freely agree to disagree. :thumbsup:
 
Lower compression makes a engine a nutless wonder at low rpms?


I have an 18:1 and yes they lose some of the torque at the very lower end but the reason I went to the 18:1 was to alleviate some of the stress of running the motor at 2400 to 2700 rpm all of the time. 4.10 gears will keep you there quite a bit.
 
Mine is definetly to low 18-1 would be better . Bill Heath was not impressed with my very low compression plan.
 
When you look at quantifying the drive energy difference btwn 2 different displacement engines, you'll find a significant difference at idle (0 boost) w/ the larger engine being a bigger air pump & moving more air.

This is because the "pressure balance" across both engines is the same. Disregarding any insignificant exh restriction at idle, the pressure is basically the same at the intake valve & exhaust valve - 1 atmosphere. When this pressure balance is equal on the 2 engines, the only variable factor is the size of the air pump, so the larger engine moves more air.

As both engines go under boost, you'll see the pressure balance become different on each engine if fitted w/ the same turbo. Still, at the same hp production, you'll see basically the same mass airflow. 275 hp made from either engine requires a similar mass of air. The 2 factors in drive energy are mass airflow & heat input.

Perhaps a more useful understanding of how turbo's are sized by turbo engineers would be useful here. This link is a reasonable example & both technically & practically correct.

http://www.turbobygarrett.com/turbobygarrett/tech_center/diesel_tech.html

They start w/ what their hp goal is. Note there's no mention whatsoever of displacement yet at this point. They first calculate the mass airflow they'll need to provide enough air to burn enough fuel, to make the hp goal.

Next they calculate what boost they expect it will take, to push that mass airflow thru the displacement engine they have at a given rpm. They're calculating the necessary boost, so they can compare how efficient different potential compressors will likely be, at the boost pressure it's gonna take to generate the mass airflow required to support the hp target.

The next example considers what will be necessary for a higher hp goal. Note they don't simply decide to use the same turbo to support a goal that differs by 100 hp. And I can assure you, a 100 hp variance in output, is far more significant on they typical 6.5's that won't likely survive beyond 350 hp. A 100 hp is a pretty significant proportion of the total 350 hp. And they feel the 100 hp difference in mass airflow on their 525 hp Duramax should use a different turbo - than the 425 hp application.

One size really doesn't fit all well folks. A 180 hp 6.5, is not the same as a 275 hp 6.5, is not the same as a 350 hp 6.5 effort.

Garretts approach to sizing turbos for diesel begins w/ understanding the hp goal, then the mass airflow requirements, then the pressure it's gonna take to move that amt of air thru your engine's displacement & rpm range.

You'll find Holsets approach is the same.

And BorgWarner's.

I totally agree we all have different backgrounds & experience to contribute. What I'm trying to point out here, is that the physics governing this stuff has absolutely no regard for us human's opinions on how it should work. The reason these 3 competing companies all have the sake take on the situation is because the physics is the same.

And there actually are some folks out there that have run the HX-35 on a 6.5 for quite some time. Reliably. Really. But they're not very interested in sharing their experiences because it's already apparently clear to the folks that haven't run HX-35's, that it can't work. Any of this sound familiar to the refugees that fled the Diesel Page turbo arguments of the past - to populate this new forum where they could freely discuss they're turbo thoughts? It should.
 
When you look at quantifying the drive energy difference btwn 2 different displacement engines, you'll find a significant difference at idle (0 boost) w/ the larger engine being a bigger air pump & moving more air.

This is because the "pressure balance" across both engines is the same. Disregarding any insignificant exh restriction at idle, the pressure is basically the same at the intake valve & exhaust valve - 1 atmosphere. When this pressure balance is equal on the 2 engines, the only variable factor is the size of the air pump, so the larger engine moves more air.

As both engines go under boost, you'll see the pressure balance become different on each engine if fitted w/ the same turbo. Still, at the same hp production, you'll see basically the same mass airflow. 275 hp made from either engine requires a similar mass of air. The 2 factors in drive energy are mass airflow & heat input.

Perhaps a more useful understanding of how turbo's are sized by turbo engineers would be useful here. This link is a reasonable example & both technically & practically correct.

http://www.turbobygarrett.com/turbobygarrett/tech_center/diesel_tech.html

They start w/ what their hp goal is. Note there's no mention whatsoever of displacement yet at this point. They first calculate the mass airflow they'll need to provide enough air to burn enough fuel, to make the hp goal.

Next they calculate what boost they expect it will take, to push that mass airflow thru the displacement engine they have at a given rpm. They're calculating the necessary boost, so they can compare how efficient different potential compressors will likely be, at the boost pressure it's gonna take to generate the mass airflow required to support the hp target.

The next example considers what will be necessary for a higher hp goal. Note they don't simply decide to use the same turbo to support a goal that differs by 100 hp. And I can assure you, a 100 hp variance in output, is far more significant on they typical 6.5's that won't likely survive beyond 350 hp. A 100 hp is a pretty significant proportion of the total 350 hp. And they feel the 100 hp difference in mass airflow on their 525 hp Duramax should use a different turbo - than the 425 hp application.

One size really doesn't fit all well folks. A 180 hp 6.5, is not the same as a 275 hp 6.5, is not the same as a 350 hp 6.5 effort.

Garretts approach to sizing turbos for diesel begins w/ understanding the hp goal, then the mass airflow requirements, then the pressure it's gonna take to move that amt of air thru your engine's displacement & rpm range.

You'll find Holsets approach is the same.

And BorgWarner's.

I totally agree we all have different backgrounds & experience to contribute. What I'm trying to point out here, is that the physics governing this stuff has absolutely no regard for us human's opinions on how it should work. The reason these 3 competing companies all have the sake take on the situation is because the physics is the same.

And there actually are some folks out there that have run the HX-35 on a 6.5 for quite some time. Reliably. Really. But they're not very interested in sharing their experiences because it's already apparently clear to the folks that haven't run HX-35's, that it can't work. Any of this sound familiar to the refugees that fled the Diesel Page turbo arguments of the past - to populate this new forum where they could freely discuss they're turbo thoughts? It should.


To make that correlation is down right insulting, saying that I am trying to say the Holset won't work is not true.There has been plenty of open discussion regarding it's use and it's option as a viable turbo for the 6.5. You are evidently very passionate to get your point across that the Holset is the turbo of choice, I disagree. Your posting of links to holset this and holset that are good information and it supports your point, so where has anyone stopped you from stating your opinion? You can;t have thin skin or get discouraged because of alternative discussion or you are guilty of the same accusation you just made.

Chill out: it is a forum, and a discussion forum at that, we are not ten year olds so keep posting. You have not convinced me: but that is my opinion and I am entitled to it, with or without anyones approvale. Are we all cosy again or would you like me to quit posting?
 
Yeah, I gotta say if we could keep this civilized there is a ton of great info here. Now I'll be the PIA. Has anybody ever tried a Banks from a 6.2 ?Any reason it would be better or worse ? Just curious since GM supoosedly(?) based the GMx on it ??
 
Yeah, I gotta say if we could keep this civilized there is a ton of great info here. Now I'll be the PIA. Has anybody ever tried a Banks from a 6.2 ?Any reason it would be better or worse ? Just curious since GM supoosedly(?) based the GMx on it ??


The banks turbos were based on a Mitsubishi TDO6 exhaust and a different compressor side, Not sure what type of compressor they used. They are also non waste gated. Not sure on much else because I have never run one.

http://www.dieselpowermag.com/tech/0907dp_turbocharger_basics/index.html

I found this to be a pretty good basics of turbo chargers
 
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[/COLOR]To make that correlation is down right insulting, saying that I am trying to say the Holset won't work is not true.There has been plenty of open discussion regarding it's use and it's option as a viable turbo for the 6.5. You are evidently very passionate to get your point across that the Holset is the turbo of choice, I disagree. Your posting of links to holset this and holset that are good information and it supports your point, so where has anyone stopped you from stating your opinion? You can;t have thin skin or get discouraged because of alternative discussion or you are guilty of the same accusation you just made.

If I can remember correctly back in the days of the place the holset was a good choice for the 18:1 builds as far as turbo options go. If I remember correctly people liked them because they built up boost quick and alot of used turbos could be found for a fair price.

Yeah, I gotta say if we could keep this civilized there is a ton of great info here. Now I'll be the PIA. Has anybody ever tried a Banks from a 6.2 ?Any reason it would be better or worse ? Just curious since GM supoosedly(?) based the GMx on it ??

The banks turbos were based on a Mitsubishi TDO6 exhaust and a different compressor side, Not sure what type of compressor they used. They are also non waste gated. Not sure on much else because I have never run one.

I thought the banks sidewinder was a mitsubisi turbo. I thought the downside of them is they only put out a few psi becuase the 6.2 had such high compression it couldnt handle much boost.
 
If I can remember correctly back in the days of the place the holset was a good choice for the 18:1 builds as far as turbo options go. If I remember correctly people liked them because they built up boost quick and alot of used turbos could be found for a fair price.





I thought the banks sidewinder was a mitsubisi turbo. I thought the downside of them is they only put out a few psi becuase the 6.2 had such high compression it couldnt handle much boost.



Correct on all counts the Banks was a Mitsubishi turbo I know the turbine housing was aTDO6 not sure if the compressor housing was from TDO6 or TDO7. They were a good design the 6.5 killed their product because of the availability of the parts, Banks kits were around 1500 to 2000 dollars which was a little pricey for most people.
 
Didn't ChicagoTDP run a Holset HX?....been running that way for quite some time iirc....
 
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