Dyno this Saturday 11am
It looks like from watching the log, that you didnt actually hit wot on the tps until about 5000rpms where you go lean. Your injector duty cycle never crosses 70% so your problem isnt there, however your computer doesnt consult your o2 sensors which shows on the graph as they both shoot right to 900mv durring the run.
From looking at run 3 which is the one the graphs are from by looking at the rpm data, as soon as PE mode is achieved about 3500 rpms your o2's spike to 900mv and stay there which means they think its rich, now obviously you cant trust narrow band o2's and your wideband use on the dyno backs it up.
If i was you i'd verify fuel pressure, and after that just look at richening the PE mode tables up to the the afr in line. Also 37 degrees of spark advance looks like alot to me for an lt1 under wot, but you're only getting 1 deg of spark retard at wot using that, i'd try a few degrees less and see if theres any power hiding in it, after i got the fuel lined out.
Also on run 3, your o2 mv's dont seem to be switching much either, Otherwise I cant say i see anything else.
From looking at run 3 which is the one the graphs are from by looking at the rpm data, as soon as PE mode is achieved about 3500 rpms your o2's spike to 900mv and stay there which means they think its rich, now obviously you cant trust narrow band o2's and your wideband use on the dyno backs it up.
If i was you i'd verify fuel pressure, and after that just look at richening the PE mode tables up to the the afr in line. Also 37 degrees of spark advance looks like alot to me for an lt1 under wot, but you're only getting 1 deg of spark retard at wot using that, i'd try a few degrees less and see if theres any power hiding in it, after i got the fuel lined out.
Also on run 3, your o2 mv's dont seem to be switching much either, Otherwise I cant say i see anything else.
Last edited by WS6T3RROR; Oct 27, 2007 at 05:08 PM.
Video of the dyno runs
http://videos.streetfire.net/video/9...d401467cc7.htm
http://videos.streetfire.net/video/9...d401467cc7.htm
Your ride already runs pretty hard, degreeing the cam or not wont cost you enough hp to make it worth fooling with in this case where its already running imo, unless you can magicly account for chain stretch which will no double retard the thing a couple of degrees after usage, so why bother outside of making sure its in right and the specs are correct.
Your air/fuel is off about 1.2-5 points where you should be making max power, that'll cost you pretty good in that rpm range. I'd venture to say 15-30hp, but every car is different, and the same dyno on different days is different to. So dont sweat the numbers too much. Track times are where its at after you get the air/fuel to a safe place.
Your air/fuel is off about 1.2-5 points where you should be making max power, that'll cost you pretty good in that rpm range. I'd venture to say 15-30hp, but every car is different, and the same dyno on different days is different to. So dont sweat the numbers too much. Track times are where its at after you get the air/fuel to a safe place.
Thread
Thread Starter
Forum
Replies
Last Post
tdigger9899
General 1967-2002 F-Body Tech
9
Sep 7, 2015 10:56 AM



