so i was wondering if someone could help me. All i know is i have to find the VE of the ca18det and its airflow in CFM to get started.. or something. Could someone please help me out with the equations?:help
Compressor maps
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iliketocrash
- Posts: 1109
- Joined: Sat May 31, 2003 5:58 am
Compressor maps
I know there have been other threads about this and i've read them and i've searched google but i can't figure it out... how do i plot points on a compressor map to match a turbo to my engine? I had a magazine at one point that explained the whole thing but it conviently seems to be missing so i was wondering if someone could help me. All i know is i have to find the VE of the ca18det and its airflow in CFM to get started.. or something. Could someone please help me out with the equations?:help
so i was wondering if someone could help me. All i know is i have to find the VE of the ca18det and its airflow in CFM to get started.. or something. Could someone please help me out with the equations?:help-
iliketocrash
- Posts: 1109
- Joined: Sat May 31, 2003 5:58 am
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westside27375
- Posts: 27
- Joined: Thu Aug 07, 2003 4:07 pm
- Car: 85' Nissan 200sx Turbo (S12)
Quote »what number did you plug in for the VE???[/quote]I dont think our engine perform at 90% Volumetric Efficency
when i was working it out i think i used 70% like SCC, one of the issues has them testing compressor maps for a 1.8 VW, just use the same calculations as they did, i'll check my magazines and post.
when i was working it out i think i used 70% like SCC, one of the issues has them testing compressor maps for a 1.8 VW, just use the same calculations as they did, i'll check my magazines and post.
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iliketocrash
- Posts: 1109
- Joined: Sat May 31, 2003 5:58 am
CA19DET wrote:I dont think our engine perform at 90% Volumetric Efficency
when i was working it out i think i used 70% like SCC, one of the issues has them testing compressor maps for a 1.8 VW, just use the same calculations as they did, i'll check my magazines and post.
"For Volumetric Efficiency, we can assume 90 percent, which should be typical for this modern five-valve DOHC engine. Of course, the actual volumetric efficiency will vary from one engine to another and from one rpm point to another, and even depending on which turbo you use, but that's what makes this a simple model." -- page 160 "Sport Compact Car", June 2003
..and they are talking about the 1.8t vw
90% VE is also used in the "Honda/Acura Engine Performance" book by Mike Kojima.
So while it may be a stretch, i'm just assuming 90% based on these two and a few other publishings i've read. So realistically it may be very well more near 85%, i'm still giving the ca18det the benefit of the doubt because its still quite an advanced peice of engineering regardless of its age.