mickeyd2005 Posted May 7, 2007 Share Posted May 7, 2007 The flow restriction is the hot side of the VF40 turbo. Link to comment Share on other sites More sharing options...
2005garnetGT Posted May 7, 2007 Share Posted May 7, 2007 The flow restriction is the hot side of the VF40 turbo. I thought we figured out the VF40 is a P18 just like the VF39? Link to comment Share on other sites More sharing options...
mickeyd2005 Posted May 7, 2007 Share Posted May 7, 2007 Is the VF39 a P18? All I know is that there is a 18 stamped on the hotside. The VF40 has a tiny hotside. I have another spare VF40 on my workbench. I'll take pictures of it and try to find the stampings. Link to comment Share on other sites More sharing options...
2005garnetGT Posted May 7, 2007 Share Posted May 7, 2007 yeah, only the VF22 and 23 are p20 iirc Link to comment Share on other sites More sharing options...
mickeyd2005 Posted May 7, 2007 Share Posted May 7, 2007 I think the P18 refers to the hotside casting and not necessarily the wheel size. The VF40 turbine is definitely tiny. It's probably the smallest IHI turbine wheel out there. Link to comment Share on other sites More sharing options...
BlackHole Posted May 7, 2007 Share Posted May 7, 2007 I think the P18 refers to the hotside casting and not necessarily the wheel size.I agree. I have a VF30 and 40 and both dimensionally appear to be the same casting (couldn't find the casting #) but the turbine outlets are very different. The VF40 turbine exducer is ~38mm, while the VF30/34/39 is ~48mm, some 60% more area. Kyle "BlackHole" Kyle "BlackHole" Link to comment Share on other sites More sharing options...
2005garnetGT Posted May 7, 2007 Share Posted May 7, 2007 I think the P18 refers to the hotside casting and not necessarily the wheel size. The VF40 turbine is definitely tiny. It's probably the smallest IHI turbine wheel out there. doh! of course it does. Link to comment Share on other sites More sharing options...
mickeyd2005 Posted May 18, 2007 Share Posted May 18, 2007 There is a good thread over on nasioc. He has the VF22 and VF23 compressor maps. The only thing that I disagree with is that he uses a constant VE (volumetric efficiency) of 85%. I think most engines breathe optimally (85 to 95%) in the mid rpm band and the efficiency is lower at idle and near redline. blackhole's VE in post #70 here seem to make more sense. http://forums.nasioc.com/forums/showthread.php?t=1265801 Link to comment Share on other sites More sharing options...
BlackHole Posted May 18, 2007 Share Posted May 18, 2007 How about this idea for calculating VE on our motors? It's simple and might give good ballpark results. The only change for LGTs would be to adjust the theoretical mass flow for boost - just measure boost in PR and multiply with the results in Eq#3. http://www.installuniversity.com/install_university/installu_articles/volumetric_efficiency/ve_computation_9.012000.htm Kyle "BlackHole" Kyle "BlackHole" Link to comment Share on other sites More sharing options...
mickeyd2005 Posted June 3, 2007 Share Posted June 3, 2007 I made an excel spreadsheet to overlay engine demand curves onto some of the compressor maps available (including IHI VF22, VF23, and VF24). The spreadsheet is located here: http://www.enginuity.org/viewtopic.php?p=18949#18949 I used BlackHole's volumetric efficiency for now. Eventually, I hope to be able to calculate it from datalogs using ride5000's method. Link to comment Share on other sites More sharing options...
BlackHole Posted June 3, 2007 Share Posted June 3, 2007 How about this idea for calculating VE http://www.installuniversity.com/install_university/installu_articles/volumetric_efficiency/ve_computation_9.012000.htm Using the aforementioned method (corrected for boost and metric units) on my dead stock 05 LGT 5MT the efficiency numbers test out as follows (a bit lower than my estimates in post #70): rpm eff 2000 79% 2500 83% 3000 87% 3500 86% 4000 86% 4500 89% 5000 88% 5500 87% 6000 84% 6500 80% avg 85% These numbers are the average of 5 test runs WOT from 2-6.5k rpm in 2nd gear. The numbers were very consistent even though the loads did change a bit (some uphill, some downhill tests). Max airflow was 202 g/sec and max boost was 0.82 bar (11.9psi), which sounds about right for an LGT. Kyle "BlackHole" Kyle "BlackHole" Link to comment Share on other sites More sharing options...
mickeyd2005 Posted June 4, 2007 Share Posted June 4, 2007 Thanks for the update. People with headers or modified AVCS tables can use the same method to come up with their own VE values. Link to comment Share on other sites More sharing options...
urfsin Posted June 4, 2007 Share Posted June 4, 2007 subscribe!!! Slide It Sideways Link to comment Share on other sites More sharing options...
BlackHole Posted June 5, 2007 Share Posted June 5, 2007 People with headers or modified AVCS tables can use the same method to come up with their own VE values. Anybody have this data? Post away! I'll be happy to post the modified formula and variables to log if anyone is interested. I'll be rechecking this as I mod, but that won't happen for a few weeks at least. Kyle "BlackHole" Kyle "BlackHole" Link to comment Share on other sites More sharing options...
ama0787 Posted June 8, 2007 Share Posted June 8, 2007 awdxboost great thread.. Did you get a lot of your examples from innovative turbos web site? Link to comment Share on other sites More sharing options...
AWDxBOOST Posted June 12, 2007 Author Share Posted June 12, 2007 i just pulled them from wherever google took me Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.