Boost air temp and air sending unit
Thread Starter
Drifting
Joined: Dec 2001
Posts: 1,313
Likes: 1
From: providence ut
Boost air temp and air sending unit
Anybody tried using the stock air sending unit to determine the boosted air temp? is it fast enough for short bursts? I tried mine last weekend and only saw a 5 degree increase. also would the temp increase be related to the restrictions in the system? a free flowing system might have less then a restricted system? I trying to determine where, at what boost to inject alcohol/water..........with this puny p600b I'm only seeing 9 psi at supercharger redline.....well maybe 10 psi.
Safety Car
Joined: May 2003
Posts: 4,283
Likes: 0
From: Houston Texas
As for where to set the water injection, you will probably have to use a diagnostic software to check KR count. Use injection to eliminate KR's so as not to retard ignition. I have not set mine up yet so I am also interested in this.
Melting Slicks
Joined: Dec 2000
Posts: 2,719
Likes: 60
From: Fremont Oh
Hi lead I responded to your other thread although it was slightly differnt form this one...
I as a rough "guestimate" us the MAF readings...
The highest NA MAF readings I got at say 5500 rpms was like 27.7 lb/min the highest I got supercharged on a good day full foot to the throttle nad no spark knock retard was 48.7 lb/min
If you take the 48.7 / 27.7 you get about 1.75
14.7 * 1.75 = 25.725
25.725 - 14.7 = 11.025
figure about 85 % efficiency 9.4 boost...
another way would be to calculate your CFM's
again using the maf sensor.. a NA estimates about 480 CFM
cu *rpm*.5*VE /1728 = CFM
350 *5500*.5 *.85 = 473.45
473.45 /14 = 33.81 Normally aspirated...
Lb/min * 14 = CFM
52.2 *14 = 730 cfm supercharged
730 / 473.45 = 1.54
14.7 *1.54 = 22.6 -14.7 = 7.93 pounds of boost...
In most cases I wouldnt think you would need water injection below 4-5 pounds of boost.... As BAM 92 said look at the knock counts that would guide you...
hope this helps, I use these just as a rough estimate .
Mo
I as a rough "guestimate" us the MAF readings...
The highest NA MAF readings I got at say 5500 rpms was like 27.7 lb/min the highest I got supercharged on a good day full foot to the throttle nad no spark knock retard was 48.7 lb/min
If you take the 48.7 / 27.7 you get about 1.75
14.7 * 1.75 = 25.725
25.725 - 14.7 = 11.025
figure about 85 % efficiency 9.4 boost...
another way would be to calculate your CFM's
again using the maf sensor.. a NA estimates about 480 CFM
cu *rpm*.5*VE /1728 = CFM
350 *5500*.5 *.85 = 473.45
473.45 /14 = 33.81 Normally aspirated...
Lb/min * 14 = CFM
52.2 *14 = 730 cfm supercharged
730 / 473.45 = 1.54
14.7 *1.54 = 22.6 -14.7 = 7.93 pounds of boost...
In most cases I wouldnt think you would need water injection below 4-5 pounds of boost.... As BAM 92 said look at the knock counts that would guide you...
hope this helps, I use these just as a rough estimate .
Mo
