1/4 Mile with AFR Map
07-23-2006, 12:56 PM
#1
Supercharged
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1/4 Mile with AFR Map
After finally fixing my vacuum leak I got the beast back on the road for a quick test run. I tried Tom Falkenberg's custom chip for his 928 Spec SCer, but the car didn't like it under cruise - it was too lean under cruise, but seemed a bit better uner WOT, but since 90% of the time I'm at cruise, I thought I should stick with my chip and plan on a tuning session. So it looks like these cars are pretty individual with a SCer eventhough you may have basically he same runnign equipment. At least with my vacuum leak fixed I no longer have any tip-in issues. 
So with everything running properly again, I decided to do a 1/4 mile run and record the AFR. The 1/4 mile run is nothing spectacular, but I was more concerned with getting a full run in so I could record the AFR.
You can see in the AFR graph that I am pretty rich on the top end (BTW I smoothed the grap a bit to make t more meaningful). I may try droping the fuel pressure a bit to see if that will help any, but I think the long term solution is to take it to a dyno tuning session in a few weeks and really get it right. I am a very happy camper.
So with everything running properly again, I decided to do a 1/4 mile run and record the AFR. The 1/4 mile run is nothing spectacular, but I was more concerned with getting a full run in so I could record the AFR.
You can see in the AFR graph that I am pretty rich on the top end (BTW I smoothed the grap a bit to make t more meaningful). I may try droping the fuel pressure a bit to see if that will help any, but I think the long term solution is to take it to a dyno tuning session in a few weeks and really get it right. I am a very happy camper.
07-23-2006, 02:12 PM
#2
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Better safe than sorry Andrew ! The theoretical power loss between max power at 13:1 and 10:1 is about 2.5%. Not a big deal - maybe 12HP in your case....
Nice run !
Nice run !
07-23-2006, 08:13 PM
#3
Race Director
I gotta agree with John.....its better to be too rich vs too lean......if the engine runs smooth the rest of the time......your sitting pretty good......but a good dyno run-tuning couldn't help either!
07-24-2006, 01:02 AM
#5
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Originally Posted by Andrew Olson
After finally fixing my vacuum leak I got the beast back on the road for a quick test run. I tried Tom Falkenberg's custom chip for his 928 Spec SCer, but the car didn't like it under cruise - it was too lean under cruise, but seemed a bit better uner WOT, but since 90% of the time I'm at cruise, I thought I should stick with my chip and plan on a tuning session. So it looks like these cars are pretty individual with a SCer eventhough you may have basically he same runnign equipment. At least with my vacuum leak fixed I no longer have any tip-in issues.
So with everything running properly again, I decided to do a 1/4 mile run and record the AFR. The 1/4 mile run is nothing spectacular, but I was more concerned with getting a full run in so I could record the AFR.
You can see in the AFR graph that I am pretty rich on the top end (BTW I smoothed the grap a bit to make t more meaningful). I may try droping the fuel pressure a bit to see if that will help any, but I think the long term solution is to take it to a dyno tuning session in a few weeks and really get it right. I am a very happy camper.
So with everything running properly again, I decided to do a 1/4 mile run and record the AFR. The 1/4 mile run is nothing spectacular, but I was more concerned with getting a full run in so I could record the AFR.
You can see in the AFR graph that I am pretty rich on the top end (BTW I smoothed the grap a bit to make t more meaningful). I may try droping the fuel pressure a bit to see if that will help any, but I think the long term solution is to take it to a dyno tuning session in a few weeks and really get it right. I am a very happy camper.
Forgive my Naiveness...what Track gives that kind of "TimeSlip"...I don't believe I have EVER seen one that looked anything like that ???
07-24-2006, 11:42 AM
#7
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whats the hp of this beast again?
interesting that your acceleration frm 60-80 is 2.5 seconds, while your 60-100 is near 5.5.
the holbert car is near 2.8 seconds 60-80 and about 6 from 60-100 at 320rwhp.
mk
interesting that your acceleration frm 60-80 is 2.5 seconds, while your 60-100 is near 5.5.
the holbert car is near 2.8 seconds 60-80 and about 6 from 60-100 at 320rwhp.
mk
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07-24-2006, 11:58 AM
#8
Supercharged
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I haven't taken it to a dyno yet, so I really don't know the HP yet, but on DR with stock exhaust (i have catless x-pipe) 459RWHP 399RWTQ. The 60-100 is pretty low because of the 2 shift points and I was not trying too hard to shift fast, I was just trying to get a halfway decent run so I could map the AFR and see what's happening. The one thing I did do this time was hit the brakes after I knew I hit 1/4 mile and brought it to a complete stop. 0-100-0 is 16 seconds. Unbelievable.