Datamaster questions....
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
Datamaster questions....and blown engine tuning
Hey guys. I spend about a half hour logging data tonight with datamaster. I have the logs if anyone is interested in helping me post them or posting the jpegs of the dyno data.
I ran the car tonight and added timing back via the btm. My car has a snow performance alky kit with about 11-12 gallons of flow. The ratio is 50/50 h2o to methanol.
I started with .75* and eventually turned it off. The most knock I saw was 1.0. At wide open throttle in 3rd, I saw zero knock from 4000-4900 when I let off. The only time I saw knock was when I hit the gas in 2nd from a roll. There would be knock for about 4-8 frames on the highest sampling rate. Maybe is this some lag before the alky kicks in?
I have the btm at zero now with is nice. I'm seeing 27* of timing at wide open throttle in 3rd.
One thing that got me thinking was the horsepowr curve dropping off from 4600 rpm on. It peaked at 479 on one run in particullar. Torque was approx 540. I have a vortech s trim which sees a max of 6lbs of boost with a 6 rib setup. The blower pulley is a 2.87.
My next question is, is this thing slipping? It doesn't go to 6 and then drop down. It goes to 6 and then doesn't climb anymore. I don't really see and fluttering of the boost guage. It seems pretty steady at 6 lbs. The boost guage climbs really quick from 2500-3500 rpms. From then on it doesn't really climb much. I'm using a 50.5" belt on there with about 300 miles on it.
I really wasn't watching the boost guage, but I don't think that it dropped down in the upper rpms.
I'm using the datamaster dyno in 3rd gear from 4300 rpm to 4900 rpm. The output smoothing setting is #2.
I'd imagine by the graph that it's slipping. With centrifugal blower, I'd expect the hp curve to climb and then level out or keep increasing as the rpm went up. My curve looks like a n/a car almost.
BTW, o2's were from 890-950 in this rpm range.
Any input is very appreciated. My goal is to get this on a wideband to really see what is going on with the afr and then lean it out a bit if possible to make more power. How do these graphs compare with other s trim vortech cars?
I ran the car tonight and added timing back via the btm. My car has a snow performance alky kit with about 11-12 gallons of flow. The ratio is 50/50 h2o to methanol.
I started with .75* and eventually turned it off. The most knock I saw was 1.0. At wide open throttle in 3rd, I saw zero knock from 4000-4900 when I let off. The only time I saw knock was when I hit the gas in 2nd from a roll. There would be knock for about 4-8 frames on the highest sampling rate. Maybe is this some lag before the alky kicks in?
I have the btm at zero now with is nice. I'm seeing 27* of timing at wide open throttle in 3rd.
One thing that got me thinking was the horsepowr curve dropping off from 4600 rpm on. It peaked at 479 on one run in particullar. Torque was approx 540. I have a vortech s trim which sees a max of 6lbs of boost with a 6 rib setup. The blower pulley is a 2.87.
My next question is, is this thing slipping? It doesn't go to 6 and then drop down. It goes to 6 and then doesn't climb anymore. I don't really see and fluttering of the boost guage. It seems pretty steady at 6 lbs. The boost guage climbs really quick from 2500-3500 rpms. From then on it doesn't really climb much. I'm using a 50.5" belt on there with about 300 miles on it.
I really wasn't watching the boost guage, but I don't think that it dropped down in the upper rpms.
I'm using the datamaster dyno in 3rd gear from 4300 rpm to 4900 rpm. The output smoothing setting is #2.
I'd imagine by the graph that it's slipping. With centrifugal blower, I'd expect the hp curve to climb and then level out or keep increasing as the rpm went up. My curve looks like a n/a car almost.
BTW, o2's were from 890-950 in this rpm range.
Any input is very appreciated. My goal is to get this on a wideband to really see what is going on with the afr and then lean it out a bit if possible to make more power. How do these graphs compare with other s trim vortech cars?
Last edited by qwiketz; Aug 22, 2005 at 10:00 PM.
Drifting
Joined: May 2003
Posts: 1,730
Likes: 1
From: Charlotte NC
St. Jude Donor '05
It has been my experience with alky injection that you can run a significantly more amount of timing or else power is lost. I would reccomend getting some dyno time as it is hard to tell what you rpicking up and losing on the street.
