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I see what you are getting at ,although your numbers for pressure loss are too low IMO.
The EFR compressors are designed to work at higher pressures than other brands and efficiency at low boost isn't so good .However compressor efficiency is not nearly as important as response so you would never fit a larger turbo with poor response just to gain a few % points of efficiency .Especially at low boost where heat from compression isn't that great anyway.
OK, and I who thought I've understood a bit on the compressor side..... Is down to inertia of the compressor wheel and power given from hotside, that response is poor at 9180?
I was at the edge of making a Matchbot thread, where we could share numbers, so not everyone have to invent the wheel over and over again. Would you be kind enough to share a printscreen of how your numbers are in the top?
I'd be guessing at the response we'd get from a 9180 but yeah .... it's got a lot more mass to accelerate. I'm basing my opinion on the poor result Turblown got with the 9174 knowing that the 9180 would be worse than that .
Why don't you start the thread and I'll chime in with the numbers I'm using . I've got to the point where I think my numbers are reasonably accurate because they match what i see in real life pretty well.
Good stuff Brett.
I would caution if you haven't done so already, is to Seal up/Cover the Block side of the OMP. Also to plug up the Line out ports.
Yeah . I made a cover for the block side which seems to be holding the oil in ok . I also bolted the plastic lines together to seal those up and put some silicone in the inlet hole in the omp to stop oil dribbling out of it and keep it clean in case I want to reuse it.
I'll be doing some more upgrades shortly . Got a new intercooler coming plus a new Synchronic DV and temp sensor . Hope to get pressure drop across the IC below 1 psi .
Thanks to some tips from jcbrx8 I'm finally able to overlay logs from the AEM failsafe .
The log below shows :
boost press - light blue
Pressure at turbo- dark blue
Pressure at turbine - red
I hope to be able to get all three lines closer together once the new IC is installed .
Note the way turbine is less than boost initially then rapidly overtakes it mid rev range
Also how Turbo pressure initially follows boost pressure then overtakes it indicating problems with pressure drop over the IC.
Per your explanation...it looks like you've mis-labeled. Seems they s/b:
"Pressure at turbo" (compressor outlet) = light/ bright blue
"Boost press" (post IC, manifold) = dark blue
Yeah . My definition of light was the lighter one in brightness which is kinda silly now that I think about it . The program chose those colours ....seems silly to get two blues !
Ok ............... these were back to back logs with a short drive to equalise temps between logs .
Bright blue : turbine backpressure
Dim blue : pressure at turbo
Red : pressure post throttle
Observations:
Boost pressure is actually MORE than pressure at turbo early in log and about the same at end of log ----- WTF ?
Pressure drop is now almost non existent which has to be a good thing BUT ...
Turbine backpressure now seems to be more jumpy and does not seem to have improved .... very confusing
Overall power (per virtual dyno) looks to be about the same .
Old IC results below ..... Note logs were not back to back for these:
Have done some testing and much head scratching................ then more mods more testing and more head scratching trying to make sense of it all . I believe I now have a handle on how this new high flow intercooler has affected things:
*It seems it actually is possible to get higher pressure post IC due to a combination of pipe diameter and temperature differences.
*Pressure drop over the IC is now miniscule ... hard to actually work out due to above but at peak power rpm there is nil drop as shown in above chart.This is an improvement of around 2.5 psi. This is due to the increased flow area (well over twice the area) in the new IC.
*There is slight reduction in turbine backpressure, although not nearly as much as I had worked out from Matchbot. Could be because the pressure fluctuations (see chart above) are making it too hard to see the real numbers.
*Although it is hard for me to know accurately (as old temp sensor was very slow and new one is very fast) , it appears that IATs are now a good 10 deg.C HIGHER at the end of a log at 14psi. I had hoped that other factors would mitigate this :
......................Lower pressure at turbo means less heat from compression .Unfortunately looking at the GTX3582 compressor map it becomes a couple of % less efficient at the same time.
.....................New intercooler has a much higher % of it's cooling surface in the actual airflow, but ............ as the old IC had approx. double the MASS of aluminium in the cooling channels ...... it had more ability to cool the air for one pull. So new IC should be less inclined to heat soak , but is less effective for one off pulls.
*Overall the engine is making slightly more power early in the pull and slightly less at the end of the pull .
*I feel that the new IC will come into it's own as I raise the boost as it will flow heaps more air without any significant increase in pressure drop.
Conclusion : Not the major improvement I had hoped for at this boost level but now that I know the pros and cons of this type of IC I may be able to make some inroads at next dyno.
Synchronic Diverter Valve :
This must have been old stock because it was supplied with perished o rings . Now that I have that sorted and got the set-up the way i like it ...i'm really liking it ! This valve is a more compact version of the original BOV they made . It can be run in push or pull mode and has a lot of tuneability.
*Sound is pleasing but not over the top (which suits me) . Currently it's recirculated so would be much louder if run VTA .
*Actuation is very quick and car feels very smooth to drive . It already was good with old BOV but it's even better now.
Have done some testing and much head scratching................ then more mods more testing and more head scratching trying to make sense of it all . I believe I now have a handle on how this new high flow intercooler has affected things:
*It seems it actually is possible to get higher pressure post IC due to a combination of pipe diameter and temperature differences.
*Pressure drop over the IC is now miniscule ... hard to actually work out due to above but at peak power rpm there is nil drop as shown in above chart.This is an improvement of around 2.5 psi. This is due to the increased flow area (well over twice the area) in the new IC.
*There is slight reduction in turbine backpressure, although not nearly as much as I had worked out from Matchbot. Could be because the pressure fluctuations (see chart above) are making it too hard to see the real numbers.
*Although it is hard for me to know accurately (as old temp sensor was very slow and new one is very fast) , it appears that IATs are now a good 10 deg.C HIGHER at the end of a log at 14psi. I had hoped that other factors would mitigate this :
......................Lower pressure at turbo means less heat from compression .Unfortunately looking at the GTX3582 compressor map it becomes a couple of % less efficient at the same time.
.....................New intercooler has a much higher % of it's cooling surface in the actual airflow, but ............ as the old IC had approx. double the MASS of aluminium in the cooling channels ...... it had more ability to cool the air for one pull. So new IC should be less inclined to heat soak , but is less effective for one off pulls.
*Overall the engine is making slightly more power early in the pull and slightly less at the end of the pull .
*I feel that the new IC will come into it's own as I raise the boost as it will flow heaps more air without any significant increase in pressure drop.
Conclusion : Not the major improvement I had hoped for at this boost level but now that I know the pros and cons of this type of IC I may be able to make some inroads at next dyno.
Perhaps it’s time for alcohol injection????
Might recover the lost cooling capacity due to the new IC while also providing additional fuel to take advantage of your increased pressure???
Of course that has tuning and alcohol sourcing implications.
Thanks for the suggestion Tom . I'm running E35 so effectively already have alcohol injection .
I have tried Water/methanol injection in the past but it didn't seem to be very effective at controlling detonation in this application .
Beautiful set up!
Dealing with the FI details does make one scratch their head from time to time.
you stated that at a certain point you had an increase of approx 2.5 lbs of boost? But less back Pressure?
IATs are approx 10c higher than ambient?
Did the maf readings change?
can you monitor exhaust gas temps?
Beautiful set up!
Dealing with the FI details does make one scratch their head from time to time.
you stated that at a certain point you had an increase of approx 2.5 lbs of boost? But less back Pressure?
IATs are approx 10c higher than ambient?
Did the maf readings change?
can you monitor exhaust gas temps?
Hey OD ...good to see you back !
Not an increase in boost ... a 2.5psi reduction in pressure drop across the intercooler. Was expecting approx. 1.5psi drop in turbine backpressure to accompany that but didn't see it , which was odd.
IATs are approx. 10C higher after a 14psi pull in 3rd gear vs previous same pull with previous intercooler.
Maf readings almost identical either way as were exhaust temps (reading obd cat temp) .
09-27-2018, 04:08 AM
Is down to inertia of the compressor wheel and power given from hotside, that response is poor at 9180?
. The program chose those colours ....seems silly to get two blues !
