Went to the track...
Went to the track... disappointed again. Couldn't run quicker than a 12.9@105. With all my mods that time is way too slow. Not sure why the car runs so slow. It feels strong and hooks without a problem. I logged the car and looked it over and the only thing that look out of the ordinary are:
1) Left Short Term counts vary from 4% lean/rich at WOT even if BLM locker is used.
2) Timing is set at 33 in my tables and varies from 36-37 in the log. I have heard though that this is not uncommon.
3) Wideband afr ratio when lean in the mid 14s ran quicker than when rich in low 13s
Anybody have any ideas what could be happening?????
1) Left Short Term counts vary from 4% lean/rich at WOT even if BLM locker is used.
2) Timing is set at 33 in my tables and varies from 36-37 in the log. I have heard though that this is not uncommon.
3) Wideband afr ratio when lean in the mid 14s ran quicker than when rich in low 13s
Anybody have any ideas what could be happening?????
definitely should be quicker. i'm scratching my head too. its like all the power is missing but the car still feels strong. weird thing is about 3 rare times during regular driving i have given it gas and its like it finds all the missing power for that one quick instance.
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Have you dyno'd it?Whats it make?What was the DA or Elevation?Sounds like maybe it's blowing thru the converter.If your having Full power randomly that sounds like Fuel or Spark issues.Are you still running an Opti?Is it good?Could be failing at high RPM's.Are your plug wires good?Any missfires detected while logging?Also you may be floating the Valves the Springs could be worn out or were never strong enough to hold.I had that same problem with about 15k on my springs the car felt slow so I dyno'd it,It was losing about 30 or 40 RWHP on the dyno from 4000 rpm on,I replaced them and got all the power back.With those mods you should be in the Mid 11's.
Last edited by LS1iFiEd; Oct 2, 2009 at 12:21 AM.
Have you dyno'd it?Whats it make?What was the DA or Elevation?Sounds like maybe it's blowing thru the converter.If your having Full power randomly that sounds like Fuel or Spark issues.Are you still running an Opti?Is it good?Could be failing at high RPM's.Are your plug wires good?Any missfires detected while logging?Also you may be floating the Valves the Springs could be worn out or were never strong enough to hold.I had that same problem with about 15k on my springs the car felt slow so I dyno'd it,It was losing about 30 or 40 RWHP on the dyno from 4000 rpm on,I replaced them and got all the power back.With those mods you should be in the Mid 11's.
Im running and MSD opti. Don't know if it is failing as the dyno curves looked good and at the track the logs showed the timing was okay. I checked the plugs and wires they are good. I didnt feel any misfires but then again i dont have a crank sensor that checks for that since mine is a 94.
The springs are less than 2K miles old and have enough pressure on the seat for the cam and its lift numbers.
DA was really low like under 100 since the elevation at the track is only +5.
when i set the afr to be what i want it to be it is a lot more lean. to get the afr in the low 13s i had to command 11.77.
at idle i have it set a 43.5. what should it be at WOT? how do i check the pressure at WOT. my gauge is behind the manifold on the schraeder vavle. i dont want to have my head and hands all in the engine bay while its at WOT.
the logs show the trims at 128 on the right side but the left side is a little erratic if switches from rich to lean throughout the run.
at idle i have it set a 43.5. what should it be at WOT? how do i check the pressure at WOT. my gauge is behind the manifold on the schraeder vavle. i dont want to have my head and hands all in the engine bay while its at WOT.
the logs show the trims at 128 on the right side but the left side is a little erratic if switches from rich to lean throughout the run.
Def. way down on power, 105mph is awefully slow - car is jumping off the line and then sleeping down the rest of the track, I ran within 2mph of your 1/8th and 1/4 speeds with a stockish car. I agree, the tune looks like it might be the issue, an afr in the 14's, if the gauge is reading right, is way off.
If the banks arn't running even, maybe you've got a goofed up injector.
Specifics on the heads/cam?
If the banks arn't running even, maybe you've got a goofed up injector.
Specifics on the heads/cam?
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Joined: Jun 2005
Posts: 173
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From: Marysville. WA
My Vette did the same thing. It would 60' ok but just felt slow and only ran 12.90 @ 107 mph. There was no miss or sudden drop off in power just slow all the way down. All i did was change the fuel pump and BAM 12.03 @116 mph. It felt like a whole new car.
Def. way down on power, 105mph is awefully slow - car is jumping off the line and then sleeping down the rest of the track, I ran within 2mph of your 1/8th and 1/4 speeds with a stockish car. I agree, the tune looks like it might be the issue, an afr in the 14's, if the gauge is reading right, is way off.
If the banks arn't running even, maybe you've got a goofed up injector.
Specifics on the heads/cam?
If the banks arn't running even, maybe you've got a goofed up injector.
Specifics on the heads/cam?
heads are stockers ported & polished 2.02 1.6 valves. cam is a comp 224/236 574/572 111lsa.
the afr is tricky since i have to command a way rich afr to get something in the 12.7 range. id have to command like an 11 afr. on the dyno the car always made the big numbers at 11.8.
my very first time on the dyno on an older setup i went to a tuner and my pump was bad it kept leaning out throughout the run. i got a racetronix kit on there now. id have to check to fuel pressure at WOT to see if its bad again.