bastarddsm
20+ Year Contributor
- 5,641
- 1,476
- Aug 26, 2003
-
Mendota,
Illinois
Ok find me one person that sets a record, or class races and is under an inducer restriction that says "ok I'll stop here I'm at the end of the map, I'm 200hp short of everyone else, but I'll stop here" Jesus a t25 is probably off the map on a stock dsm.
As for maps are for nerds, look at the HTA86, I'm not an FP nutswinger, but damn if it doesn't work. Look how many cars in the 9's on it, or even a few in the 8's, on a 61mm compressor. The lack of compressor maps clearly has not slowed anyone down with that. Meanwhile the turbo nerds are busy studying maps and can't break 11's. I will admit there is a time and a place for using the maps, but 99% of people don't have the knowledge needed to use them. That includes you and I.
You also can't read well, I never once talked about loosing efficiency with closing the vanes. I never even said I was positive that your turbo would have much effect on turbine efficiency with the nozzle opening. In fact I mentioned that I thought it wouldn't, and that in the case of my turbo i implied that closing the vanes should improve efficiency, to a point.
You just keep missing the point I'll lay some facts out for you.
1. A HX40 in a BEP doesn't spool that much slower than what you have. I'm sure the VGT can do better, but it's not like 2 fold
2. An HX40 in a bep doesn't start having back pressure issues until you get to the 30psi+ area
3. At 30psi and 8000 rpm a decently setup 4g is going to be in the 60+lb/min range. That's getting near the choke region of an HX40 compressor. The compressor efficiency is heading downward fast at that point.
4. The compressor power requirements, and the compressor rpm is increasing rapidly as well.
5. A decent turbine map will show you that as you get past peak efficiency increasing rpm lowers turbine efficiency.
6. Declining efficiency on each side means a rapidly increasing enthalpy requirement.
7. You are not going to open the nozzle your way out of increasing backpressure as you get close the the limit of the compressor
I've said it several times, the turbine side operates in choke nearly always, so I don't know how you keep getting confused. There's no reason to distinguish between compressor and turbine choke because the turbine is always choked. You also need to remember the turbo is a SYSTEM, when you operate the compressor outside of it's peak efficiency, you are also operating the turbine outside of that area too. Unless the turbo is poorly designed.
I told you to calculate this. You havn't tried, either you know I'm right, or you don't know how to. And in that case you really " have a lot to learn about radial inflow turbines"
As for my car, I hope you realize there are tons and tons of OEM wheels that garret doesn't publish the map for right? Mine was a gtx style with a small hub and all major blades. - A design that clearly trades flow capacity for efficiency(moving the surgeline to the left ), and is nothing like the 57/88 wheel out of a powerstroke, but you knew that right? Because you can calculate the performance of a setup you have no clue about?
You know why I don't publish a tech article? Because I don't know enough to do that, and if I did, I'd just a have little dickweeds trying to refute everything.
As for maps are for nerds, look at the HTA86, I'm not an FP nutswinger, but damn if it doesn't work. Look how many cars in the 9's on it, or even a few in the 8's, on a 61mm compressor. The lack of compressor maps clearly has not slowed anyone down with that. Meanwhile the turbo nerds are busy studying maps and can't break 11's. I will admit there is a time and a place for using the maps, but 99% of people don't have the knowledge needed to use them. That includes you and I.
You also can't read well, I never once talked about loosing efficiency with closing the vanes. I never even said I was positive that your turbo would have much effect on turbine efficiency with the nozzle opening. In fact I mentioned that I thought it wouldn't, and that in the case of my turbo i implied that closing the vanes should improve efficiency, to a point.
You just keep missing the point I'll lay some facts out for you.
1. A HX40 in a BEP doesn't spool that much slower than what you have. I'm sure the VGT can do better, but it's not like 2 fold
2. An HX40 in a bep doesn't start having back pressure issues until you get to the 30psi+ area
3. At 30psi and 8000 rpm a decently setup 4g is going to be in the 60+lb/min range. That's getting near the choke region of an HX40 compressor. The compressor efficiency is heading downward fast at that point.
4. The compressor power requirements, and the compressor rpm is increasing rapidly as well.
5. A decent turbine map will show you that as you get past peak efficiency increasing rpm lowers turbine efficiency.
6. Declining efficiency on each side means a rapidly increasing enthalpy requirement.
7. You are not going to open the nozzle your way out of increasing backpressure as you get close the the limit of the compressor
I've said it several times, the turbine side operates in choke nearly always, so I don't know how you keep getting confused. There's no reason to distinguish between compressor and turbine choke because the turbine is always choked. You also need to remember the turbo is a SYSTEM, when you operate the compressor outside of it's peak efficiency, you are also operating the turbine outside of that area too. Unless the turbo is poorly designed.
I told you to calculate this. You havn't tried, either you know I'm right, or you don't know how to. And in that case you really " have a lot to learn about radial inflow turbines"
As for my car, I hope you realize there are tons and tons of OEM wheels that garret doesn't publish the map for right? Mine was a gtx style with a small hub and all major blades. - A design that clearly trades flow capacity for efficiency(moving the surgeline to the left ), and is nothing like the 57/88 wheel out of a powerstroke, but you knew that right? Because you can calculate the performance of a setup you have no clue about?
You know why I don't publish a tech article? Because I don't know enough to do that, and if I did, I'd just a have little dickweeds trying to refute everything.