Pat's Ebay Turbo Compound Boost Build
#1461
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Small post-thanksgiving update. I wanna race tomorrow if possible, so I needed to look into the oil pump issue. Long term I think I'm gonna build my own electric oil pump with parts that are designed to run >10K hours without failure. (EDIT: also if this pump I make works as well as I want, I'd like to install one on the engine too so I can turn on oil pressure before startup) But for now, I need something that works so I can race.
First, I pulled out my old pump I used to run. It worked, pumped, didn't leak, but had thermal protection that would kick in when racing on a hot day after a lot of driving which would shut the pump off for a minute or two until it cooled off a bit. That pump, I pulled it apart, and disabled the thermal shutdown protection. Tested it and it works, but sounds like it might need a bearing at some point but it's working.
Then I figured, why not take apart the pump that is currently acting up in the car and see what's up with it. At this point I have a functional replacement anyways. I figured it was worn brushes as occasionally it wouldn't start, but tap the motor and is spun to life. Also it sounded like it was speeding up/slowing down when running as if the brushes were going in/out of contact. Took apart, sure enough, had a stuck brush. Upon further inspection, it looks like there were two manufacturing defects. That brush holder was too tight and squeezing the brush too much, not letting the spring advance the brush as it wears. Second, that brush holder was not straight! It was like 15-20* off. It should be square with the armature. I fixed both issues, put it back together, and it seems fine now. I setup a timer on my phone, and pulsed the pump on briefly ever time the second counted up. Did that for 3.5 minutes, it never failed to spin up and sounds normal.
Plan is to bench test the second pump I tested for 3.5 minutes tomorrow, let it pump oil for a few hours and make sure it's working normally, then it's going back in the car. Probably throw the noisy pump in the trunk as a spare in case I need it.
Still haven't driven the car with the new turbo, so really looking forward to that! Hopefully there are no major issues.
First, I pulled out my old pump I used to run. It worked, pumped, didn't leak, but had thermal protection that would kick in when racing on a hot day after a lot of driving which would shut the pump off for a minute or two until it cooled off a bit. That pump, I pulled it apart, and disabled the thermal shutdown protection. Tested it and it works, but sounds like it might need a bearing at some point but it's working.
Then I figured, why not take apart the pump that is currently acting up in the car and see what's up with it. At this point I have a functional replacement anyways. I figured it was worn brushes as occasionally it wouldn't start, but tap the motor and is spun to life. Also it sounded like it was speeding up/slowing down when running as if the brushes were going in/out of contact. Took apart, sure enough, had a stuck brush. Upon further inspection, it looks like there were two manufacturing defects. That brush holder was too tight and squeezing the brush too much, not letting the spring advance the brush as it wears. Second, that brush holder was not straight! It was like 15-20* off. It should be square with the armature. I fixed both issues, put it back together, and it seems fine now. I setup a timer on my phone, and pulsed the pump on briefly ever time the second counted up. Did that for 3.5 minutes, it never failed to spin up and sounds normal.
Plan is to bench test the second pump I tested for 3.5 minutes tomorrow, let it pump oil for a few hours and make sure it's working normally, then it's going back in the car. Probably throw the noisy pump in the trunk as a spare in case I need it.
Still haven't driven the car with the new turbo, so really looking forward to that! Hopefully there are no major issues.
#1462
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Doing some bench testing on the BMW oil pump. I wanted to try running it at a lower voltage as I figured that would lower the temps/load on the pump which would improve reliability. Running it at 13.0V, the motor temp went 100*F over ambient in about 15 minutes. I tried adding a 1 ohm 100W rated resistor inline, and that dropped the pump voltage a lot, slowed it down, and of course temps dropped a lot. Then tried two 1 ohm resistors in series, that got the pump voltage down even more. I *think* I can get away with this lower voltage on the car, will test that soon. But on the bench, it looks much better. I built a little oil circuit for the pump, and measured pump voltage, oil temp, electric motor temp, resistor temp, resistor heat sink temp.
With the two inline resistors, after running for 15 minutes motor temp is up 10*F over ambient (before was 100*F). The resistor pack is now on a heat sink and they are running about 100*F over ambient (was over 200*F over ambient without heatsink). Motor temp is up about 34*F over ambient after an hour of running and seems to be stabilizing.
Of course the pump speed is much reduced with lower voltage, but I think it will be adequate on the car as there isn't that much oil draining out of the turbo. Doing a 2 hour test right now, if it passes that it's going on the car and will test it there.
With the two inline resistors, after running for 15 minutes motor temp is up 10*F over ambient (before was 100*F). The resistor pack is now on a heat sink and they are running about 100*F over ambient (was over 200*F over ambient without heatsink). Motor temp is up about 34*F over ambient after an hour of running and seems to be stabilizing.
Of course the pump speed is much reduced with lower voltage, but I think it will be adequate on the car as there isn't that much oil draining out of the turbo. Doing a 2 hour test right now, if it passes that it's going on the car and will test it there.
#1463
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No racing tonight, but did get a few miles on new setup and took some measurements and whatnot.
I moved the intercooler further down in the bumper and ducted it really well. Goal was to lower air temps.
Doing a 2-3 pull from the same speeds/boost levels:
Before: Air temp climbed 11.05*F/sec, and peak temps were 48.1*F above ambient.
Now: 6.82*F/sec, peak temps were 25.8*F above ambient.
So big improvement! Peak temps are much lower, and the rate of air temps climbing is also greatly reduced. Yes I changed turbo, and I'm sure there's some efficiency whatever that's contributing, but IMO primary thing is placement of intercooler.
Very happy air temps are much better, I was hoping for a significant improvement and I got it.
Ok, on to EFR... Spool is about the same as before. It's a touch better, but not that much, I honestly expected it to be a much bigger difference. It feels faster when it is spooling which is nice, but the actual time to boost doesn't appear much better. However, power is definitely up. The EFR @ 18 PSI pulls about as good as the ebay turbo did at 22-23 PSI.
Comparing AFR, duty cycle, air temp data of before/after, it's clear the EFR flow more air at a given boost level. At the 30-31 PSI boost level, before duty cycle was around 70-72% and it was richer than target. Now duty is at 84%, and it's not rich of target... So clearly flowing more air.
Oil pump issues, I'm not sure yet. I dumped a ton of oil in the muffler when the pump originally died, so it's an oily mess. I think I may need to speed the pump up a bit more in boost, but not sure. Gonna drive it more and see if everything clears up after putting some miles on it. But the pump temps are much better.
Also I heard a weird noise when I shut the car off. Apparently the EFR spins for like 20-30 seconds after turning the key off. LOL, I popped the hood and started looking around wondering WTF that sound was.
I moved the intercooler further down in the bumper and ducted it really well. Goal was to lower air temps.
Doing a 2-3 pull from the same speeds/boost levels:
Before: Air temp climbed 11.05*F/sec, and peak temps were 48.1*F above ambient.
Now: 6.82*F/sec, peak temps were 25.8*F above ambient.
So big improvement! Peak temps are much lower, and the rate of air temps climbing is also greatly reduced. Yes I changed turbo, and I'm sure there's some efficiency whatever that's contributing, but IMO primary thing is placement of intercooler.
Very happy air temps are much better, I was hoping for a significant improvement and I got it.
Ok, on to EFR... Spool is about the same as before. It's a touch better, but not that much, I honestly expected it to be a much bigger difference. It feels faster when it is spooling which is nice, but the actual time to boost doesn't appear much better. However, power is definitely up. The EFR @ 18 PSI pulls about as good as the ebay turbo did at 22-23 PSI.
Comparing AFR, duty cycle, air temp data of before/after, it's clear the EFR flow more air at a given boost level. At the 30-31 PSI boost level, before duty cycle was around 70-72% and it was richer than target. Now duty is at 84%, and it's not rich of target... So clearly flowing more air.
Oil pump issues, I'm not sure yet. I dumped a ton of oil in the muffler when the pump originally died, so it's an oily mess. I think I may need to speed the pump up a bit more in boost, but not sure. Gonna drive it more and see if everything clears up after putting some miles on it. But the pump temps are much better.
Also I heard a weird noise when I shut the car off. Apparently the EFR spins for like 20-30 seconds after turning the key off. LOL, I popped the hood and started looking around wondering WTF that sound was.
#1465
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Pat, why make your own pump? If you want an oil pump designed to run >10k hours just buy a damn industrial hydraulic gear pump. Get the tiniest one they make and run it at half voltage (ie buy a 24v one because its still going to be too big for your flow) and that thing should last forever. Of course its going to be a big chunk of iron.
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Pat, why make your own pump? If you want an oil pump designed to run >10k hours just buy a damn industrial hydraulic gear pump. Get the tiniest one they make and run it at half voltage (ie buy a 24v one because its still going to be too big for your flow) and that thing should last forever. Of course its going to be a big chunk of iron.
#1467
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Something like this https://www.mcmaster.com/#6296k44/=1afiudn
with this on it NEMA 48C Stainless Steel 12V-NEMA 48C Stainless Steel DC Motors 12V-NINGBO ESON MOTOR CO.,LTD.
That ought to give a pump that moves about 1/4 gallon per minute. Find a faster motor to go faster. Since you're not trying to do more than overcome a few psi worth of head you can use a really wimpy (comparatively to the pump input power rating) motor on it.
with this on it NEMA 48C Stainless Steel 12V-NEMA 48C Stainless Steel DC Motors 12V-NINGBO ESON MOTOR CO.,LTD.
That ought to give a pump that moves about 1/4 gallon per minute. Find a faster motor to go faster. Since you're not trying to do more than overcome a few psi worth of head you can use a really wimpy (comparatively to the pump input power rating) motor on it.
#1468
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Its called a scavenging pump, if that helps you find a cost effective one.
https://www.rbracing-rsr.com/oilsystems.htm
should only need one 03-1034 with AN8 lines
https://www.rbracing-rsr.com/oilsystems.htm
should only need one 03-1034 with AN8 lines
Use check valves on feed to each turbo (or just the remote mounted one) and one on pump exit.
#1469
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Something like this https://www.mcmaster.com/#6296k44/=1afiudn
with this on it NEMA 48C Stainless Steel 12V-NEMA 48C Stainless Steel DC Motors 12V-NINGBO ESON MOTOR CO.,LTD.
That ought to give a pump that moves about 1/4 gallon per minute. Find a faster motor to go faster. Since you're not trying to do more than overcome a few psi worth of head you can use a really wimpy (comparatively to the pump input power rating) motor on it.
with this on it NEMA 48C Stainless Steel 12V-NEMA 48C Stainless Steel DC Motors 12V-NINGBO ESON MOTOR CO.,LTD.
That ought to give a pump that moves about 1/4 gallon per minute. Find a faster motor to go faster. Since you're not trying to do more than overcome a few psi worth of head you can use a really wimpy (comparatively to the pump input power rating) motor on it.
Its called a scavenging pump, if that helps you find a cost effective one.
https://www.rbracing-rsr.com/oilsystems.htm
should only need one 03-1034 with AN8 lines
https://www.rbracing-rsr.com/oilsystems.htm
should only need one 03-1034 with AN8 lines
Use check valves on feed to each turbo (or just the remote mounted one) and one on pump exit.
I have a checkvalve on the turbo feed, it didn't make any difference in anything. I meant to remove it a while back but forgot...
Small update, but I did some ignition coil testing to see if I have a bad coilpack. I setup a test rig with a 1/2" spark gap to see if each coil could do that, as 1/2" gap in air takes about 40k Volts to spark, and that's what the coils are rated at. All four coils could do it above 2ms dwell. Got some sweet arcing videos of it I could upload if anyone wants to see how nasty these IGN1A coils are.
So if spark is great, but it still misfires with a .015" gap.... WTF. I'm gonna try some iridium plugs as those are supposed to be easier to fire. See if that helps or fixes it. I ordered some, picked them up, but they won't work as I ordered the wrong ones. New ones will be ordered tomorrow.
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Anyone got some ideas to improve torque in the 2,500-4,500 RPM range? Once the turbos spool, she goes, but it's slow to spool. I'm going to try unhooking my quickspool valve to see if that improves the front turbo spool with the EFR.
What ideas do yall got? I know, nitrous would work, and if I can't come up with anything better, it will get nitrous. But I wanted to try any other ideas before going that route.
What ideas do yall got? I know, nitrous would work, and if I can't come up with anything better, it will get nitrous. But I wanted to try any other ideas before going that route.
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I've seen a 50 shot spool an RB26 1000 rpm earlier and generate 150whp more (instead of just 50) at the same rpm as the original spool up rpm. It was then tapered off with a boost sensitive switch so once the engine was at 15psi nitrous was off.
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Thanks.
Thanks as well.
Would work, but not doing all that.
1- How could I do antilag with an auto? The problem is now, the car goes up to about 3K when I floor it, and sits there not making crap for boost. It sits on the converter. I guess I could literally try it, but being an auto that stalls at 3K, it's going to stall lower than that if I turn on antilag and I'm guessing that will not help anything, but I haven't tried it either so I don't really know.
2- Thanks, that seems a common suggestion
4- Jesus is that stuff volatile. I looked it up, autoignition temp is -4*F. LOL
I think I know the car/video you are talking about. I'd forgotten about it, I'll go find it and watch it again.
The only exotic thing I could think of that I might could do, is a copy of this system Volvo built:
That, or a variation of it that puts the compressed air right into the motor. But I did some preliminary numbers and you would need a 5 gallon tank to store enough air to have any chance of it delivering significant boost for 1 second at 3K RPMs.
Thanks as well.
2- Thanks, that seems a common suggestion
4- Jesus is that stuff volatile. I looked it up, autoignition temp is -4*F. LOL
The only exotic thing I could think of that I might could do, is a copy of this system Volvo built:
That, or a variation of it that puts the compressed air right into the motor. But I did some preliminary numbers and you would need a 5 gallon tank to store enough air to have any chance of it delivering significant boost for 1 second at 3K RPMs.