Holset Compressor Maps I've scurried up
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Holset Compressor Maps I've scurried up
Holset maps are pretty hard to find compared to Garretts it seems. Some of these are home made, and one set I've seen labeled different from different forums I've found them in. I labeled them the best I knew. Be aware some are metric (Kg/hr or min), some are in mass flow rate (lb/hr or min), and some are in volumetric flow rate (CFM). Either way, maybe people can get something out of these or throw in their $0.02 if they see somethin incorrect.
HX35 (in CFM)
HX40 vs Super HX40 (metric, not lb/min)
HX40 vs Pro 52 (metric, not lb/min)
HX40 vs Super HX40 vs Super 52 (metric, not lb/min)
This was posted as an HE351 (not sure if CW or VE)
This one is debateable: I've seen different turbo references on this. When the math is done out and compared to others, the GREEN is an Hx35, the RED is an HE351, and the BLACK was listed as "New Hy35" (??)
And finally a useless Hx30 (for 6bts anyway). Its my only legit looking map with efficiency islands. I have one of an HX40 that is equally as legit, but it uploaded funny, I'll try again later.
HX35 (in CFM)
HX40 vs Super HX40 (metric, not lb/min)
HX40 vs Pro 52 (metric, not lb/min)
HX40 vs Super HX40 vs Super 52 (metric, not lb/min)
This was posted as an HE351 (not sure if CW or VE)
This one is debateable: I've seen different turbo references on this. When the math is done out and compared to others, the GREEN is an Hx35, the RED is an HE351, and the BLACK was listed as "New Hy35" (??)
And finally a useless Hx30 (for 6bts anyway). Its my only legit looking map with efficiency islands. I have one of an HX40 that is equally as legit, but it uploaded funny, I'll try again later.
#2
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flow charts are like reading chinese to me. It makes no sense at all.
What boost pressure is the he351 most comfortable running with and what's it's flowrate? and how does it compare to a super 40?
Sorry for my ignorance. Or if someone could explain how to read one of these flow charts in lamans terms I would also really appreciate that.
What boost pressure is the he351 most comfortable running with and what's it's flowrate? and how does it compare to a super 40?
Sorry for my ignorance. Or if someone could explain how to read one of these flow charts in lamans terms I would also really appreciate that.
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Pressure ratios are on the left Y axis. Atmospheric pressure around all the time is approximately 14.696 psia or just 14.7 psia. We usually don't pay attention to the atmospheric pressure when we talk about boost and we think of the air around us as 0 psig. For this map, the pressure ratio begins at the bottom as 14.7 psia (0 psig). Move up the Y axis and when you get to Pressure ratio of 2.0, this means 2 atmospheric pressures... or 29.4 psia (or 14.7 psig, this is what your boost gauge would read). And so and and so forth for 3.0 and 4.0.
The maximum on the HE351 map (assuming this IS the HE351) is a PR of 4.2.
4.2 * 14.7 psia = 61.7 psia
This is an absolute pressure, now subtract the atmospheric pressure around us constantly and this is what your boost gauge will show
61.7 psia - 14.7 psia = 47 psig (boost gauge read out). This is just the MAXIMUM on the map. It will go further, they just don't recommend it. If you were running this boost at 30lb/min of air flow (taken from the Y axis) you can pun point a spot on the grid. See the lines that slop down to the right? That is the approximate SPEED of the turbo. At that spot, the turbo is turning 144,000 RPM!
See how the lines all make small "islands" with percentages in them? This is the efficiency islands. Trying to get your set up to run closer to the middle of the middle island will result in the most efficient (and cool) place to run your turbo. Looks like 29psi of boost (PR of 3.0) at 40lb/min of flow will keep you still around the 74% efficiency island which is pretty good. Of course you can go more.
The line all the way to the left is the surge line. You don't want to be running over there. There is too much pressure, but not enough flow. The compressor will want to run itself backwards in those zones. This could happen if you were running high boost and let off the throttle quick. Your flow demand just cut drastically but you still have plenty of boost in the intake manifold. Your turbo wants to be driven BACKWARDS here and will make a loud noise (turbo bark). Not as much of a problem with diesels as we have no intake throttle plate, but gassers MUST have a blow of valve (BOV) to allow the turbo to spool down with enough air flow when the throttle is let off suddenly
BTW, these are all just VERY ROUGH calculations. There are so many factors in play with ambient pressures, temperatures, and I think even humidity. Some of these maps were made with different reference pressures (one as low as 13.9psia). I also want to note again. I am not 100% on the accuracy of these maps, but they might be a reference. I'm hoping some people will be able to confirm or deny accuracy of the he351 maps especially. I have doubts over these as they only seem to flow a LITTLE more than an HX35. The engines that came with the HX35 were only 160-215hp stock. The engines with the HE351 (5.9L HO's) had 325hp stock.
The maximum on the HE351 map (assuming this IS the HE351) is a PR of 4.2.
4.2 * 14.7 psia = 61.7 psia
This is an absolute pressure, now subtract the atmospheric pressure around us constantly and this is what your boost gauge will show
61.7 psia - 14.7 psia = 47 psig (boost gauge read out). This is just the MAXIMUM on the map. It will go further, they just don't recommend it. If you were running this boost at 30lb/min of air flow (taken from the Y axis) you can pun point a spot on the grid. See the lines that slop down to the right? That is the approximate SPEED of the turbo. At that spot, the turbo is turning 144,000 RPM!
See how the lines all make small "islands" with percentages in them? This is the efficiency islands. Trying to get your set up to run closer to the middle of the middle island will result in the most efficient (and cool) place to run your turbo. Looks like 29psi of boost (PR of 3.0) at 40lb/min of flow will keep you still around the 74% efficiency island which is pretty good. Of course you can go more.
The line all the way to the left is the surge line. You don't want to be running over there. There is too much pressure, but not enough flow. The compressor will want to run itself backwards in those zones. This could happen if you were running high boost and let off the throttle quick. Your flow demand just cut drastically but you still have plenty of boost in the intake manifold. Your turbo wants to be driven BACKWARDS here and will make a loud noise (turbo bark). Not as much of a problem with diesels as we have no intake throttle plate, but gassers MUST have a blow of valve (BOV) to allow the turbo to spool down with enough air flow when the throttle is let off suddenly
BTW, these are all just VERY ROUGH calculations. There are so many factors in play with ambient pressures, temperatures, and I think even humidity. Some of these maps were made with different reference pressures (one as low as 13.9psia). I also want to note again. I am not 100% on the accuracy of these maps, but they might be a reference. I'm hoping some people will be able to confirm or deny accuracy of the he351 maps especially. I have doubts over these as they only seem to flow a LITTLE more than an HX35. The engines that came with the HX35 were only 160-215hp stock. The engines with the HE351 (5.9L HO's) had 325hp stock.
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DZL Damon, you are the man. Thanks alot. I'm subscribed. I just bought a regular Garrett 3788R. Not the dodge one. Mine will flow 67lbs/min. The dodge stage 3 garrett flow's 70lbs/min. Maybe a tad more. Anyhow, I'm putting it on the 03 with HE341. Have you found a map for a 341? B/c I can't. That map above, "new HY35" is what I'd call a HE341 b/c it is sometimes called a HY35W or something to that affect. But, There's no way a 56inducer 83exducer wheel is outflowing a HE351CW 60-88 wheel. Not when they're both regular Holset wheels. IE not ETT wheels from BW or Garrett GTX wheels. So, I'm saying I think the red is a 341 and the black is a 351. What do you think about my assesment. And do you have a 341 map? I'd like to see what I've got in comparison to what I'm going to. Thanks, Bill
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I'm looking for a HE341 map. I'm actually a little upset that a HE351CW maps out higher than the 63.5mm garrett I just bought. But I know the garrett will spool sooner. Oh well.
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Sorry, I don't have anymore maps. I dug these up before I had my CTD's. I found them on MB diesel forums that people had posted to from various ricer forums.
#9
cheers,
Douglas
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You engineers are giving me a headache
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