Guest the_dj Posted July 2, 2002 Share Posted July 2, 2002 Well now. My adventures never stop. Right at the end of my last update, I was about to take the car out to check fuel pressure at WOT. Then the downpour starts. Anyway, I was able to take it out. Results of WOT fuel pressure check: 18-20psi at WOT. I was like That has GOT to be bad. Long story short, I replaced my fuel filter, and pressure holds steady at 45psi for a good run through second, but the computer is still reporting a bit lean. .73-.71 volts from O2 sensor (should be .80 +/- .05). I go home to take off the pressure gauge so I can start some real tuning. Another downpour. Downpour stops, give time for road to dry up a bit. Time for another drive. Felt slightly weaker and O2 was now saying .69-.71, and the only change was I raised the fuel map some where it was saying .71-.71. The BAM I hit a BRICK WALL at 3400 rpm. How in the HECK did the rev limiter get set for 3150rpm begin limit and 5200rpm high limit. Quick change to computer sets it to 5600 low and 5800 high. Result of rev limit change: limit in 1st gear 4000rpm, and limit in other gears 3500rpm. WTF!? So now the map is raised as much as I can, timing feels a little off, lack of power, O2 is reporting lean, crazy rev limit at 3500-4000 rpm (will NOT go above 4000, even in neutral), and the fuel pressure gauge said proper pressure under all loads just a second earlier. The only thing that changed was it got rained on for a bit. This car is an adventure. Why won't it just run RIGHT??? And FI is supposed to be nice and easy to tune. Thanks, Sam Quote Link to comment Share on other sites More sharing options...
QWKDTSN Posted July 2, 2002 Share Posted July 2, 2002 Sam, sorry if this is totally not answering your question at all, but what car do you drive and what engine combo do you have in it? Your homepage only shows the 280ZX with a leaf blower and PVC pipe exhaust Quote Link to comment Share on other sites More sharing options...
Guest the_dj Posted July 2, 2002 Share Posted July 2, 2002 AHAHAHHAAHAHAH. We did the stupidest stuff to that car and had a BLAST doing it!! Current car: 1978 280Z 300hp 350 crate motor TPI Intake manifold Holley Commander 950 computer Accel 24# injectors MSD 6AL ignition box 3/8" braided stainless fuel lines NEW MSD inline high flow/high pressure fuel pump NEW inline fuel filter T56 tranny/R200 rear end Thanks, Sam Quote Link to comment Share on other sites More sharing options...
Guest greimann Posted July 2, 2002 Share Posted July 2, 2002 Sam, Provide this info to me so I can look it over, if you want me to: Fuel map in a spreadsheet Spark curve in a spreasheet Duration offset Temperature compensation values. or, A copy of the Holley software and your file. Quote Link to comment Share on other sites More sharing options...
Guest greimann Posted July 2, 2002 Share Posted July 2, 2002 Just noticed something else. You have an MSD 6AL. What rev limit is set on that thing? Quote Link to comment Share on other sites More sharing options...
Guest the_dj Posted July 3, 2002 Share Posted July 3, 2002 Hey guys. I haven't slept in 30+ hours. I would post all the spreadsheets but I'm pooped. Look for them tomorrow in this thread. Greimann: I can't recall anything about a duration offset. Does it have to do with spark or fuel or what? Concerning the rev limit: The rev limit used to be set at 6100rpm, and I know for a fact that it would rev that high without hesitating. That's way past the realistic shift point but there was certainly no limiting involved. The MSD was installed at the time, so the rev limiter in it (which I don't use) is set somewhere above that. I use the Holley rev limiter for anything. It say it is set for 5600-5800rpm, but there is no way outside of a painful downshift to get that engine above 4000rpm right now. Sam Quote Link to comment Share on other sites More sharing options...
Guest greimann Posted July 3, 2002 Share Posted July 3, 2002 Hey, no sleep for the wicked! Duration offset is a parameter in my software (original Holley 4Di) that moves the entire fuel map up or down a percentage. Normally it is set at 50% so you have room either way to bump the entire map. Commander 950 software may call this something different, not not have it. I have never seen the latest version. Quote Link to comment Share on other sites More sharing options...
Guest the_dj Posted July 4, 2002 Share Posted July 4, 2002 Well, after months of working on the fuel system for my car, it seems I finally got things straightened out. I could never beat an LS1 (98+ V8 camaro/firebird) before, but I could hold with one from the line and it would only get me by a car to 70. Now, I had my friend with me to help with tuning and monitoring the computer. My car weighs 2720 loaded, plus 150 for me, and 300 for him. That's 3170 race weight. I timed a 5 second FLAT (5.0) 0-60. I was like Now, weight is my SERIOUS advantage. The weight of a passenger affects my performance more than it does on a heavy car (higher percentage of relative mass). How much do you think I could do a 0-60 with him not in the car, with a race weight of only 2870? Needless to say, I am VERY happy with the way it is running right now. And that turbo/intercooler is still yet to be installed but hopefully by the end of the month. Sam Quote Link to comment Share on other sites More sharing options...
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