Calgary280ZT Posted March 31, 2010 Share Posted March 31, 2010 JimCanuck (he's going to join this discussion later with more technical info) checked the timing on the Z tonight. Car has been sluggish off the line, into boost at low rpms...mimicked performance from two years ago when Jim retarded the mechanical advance by 8 degrees (just not quite as bad). Well, Jim figures there's 10 degrees of static advance (hope I've got the terms correct). And the distributer is advanced as far as it can go. Manual says there should be 20 degrees, and we changed it before it read 28 (Jim lowered it to 20, engine ran like crap, put it back up to 28, ran like a champ). When we installed the Rebello head and Isky cam, Dave Rebello told us to put the cam sprocket on the first hole, which we did. I'm using one of Bo's old V500 tunes and haven't changed the advance curve at all. We don't know where to begin. First order of business would seem to be to get the static advance(?) back to 20. Cam sprocket, distributer, something else? Where should we begin looking? V500 ignition map? I'm reluctant to start there, just because we're using a map that's already been proved by Bo. Seems to me we should leave it alone for now, but maybe I'm wrong. Any comments appreciated. Markham Quote Link to comment Share on other sites More sharing options...
Bernardd Posted March 31, 2010 Share Posted March 31, 2010 Mark, the dampner or timing mark may have moved on the crank sensor setup, the ecu may think it's warming or maybe something changed in the ignition modifiers maps. Post pics of those. Is this a coilpack setup? Are you reading of cyl 1? Just throwing some things out there... Quote Link to comment Share on other sites More sharing options...
Calgary280ZT Posted March 31, 2010 Author Share Posted March 31, 2010 Bernie, damper hasn't moved, Jim and I had it off a few months ago and it was fine. Something wrong with the ignition maps is a possibility. I'll post those later today if I have a chance. Not using a coil pack. Reading off cyl 1? Yoiks, not sure, I'll let Jim or Bo answer that one. Mark, the dampner or timing mark may have moved on the crank sensor setup, the ecu may think it's warming or maybe something changed in the ignition modifiers maps. Post pics of those. Is this a coilpack setup? Are you reading of cyl 1? Just throwing some things out there... Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted March 31, 2010 Administrators Share Posted March 31, 2010 Are you saying the timing has changed with no change to the software? If so, the most likley cause would be the spur gear on the quill shaft slipping. It's only pressed on... a roll pin is a good idea on these motors. Set "Timing Lock" to something reasonable (10 degrees, for example) and make absolutley certain actuall timing matches. If it doesn't, it will need to be adjusted either mechanically, or via the software. If adjusting with software, use the parameter "REF Degrees BTDC". Once matched, turn "Timing Lock" off. Quote Link to comment Share on other sites More sharing options...
Calgary280ZT Posted April 1, 2010 Author Share Posted April 1, 2010 Ron, software hasn't changed. To tell the truth, we haven't had a timing light on the engine since changing to the V500...embarrassing, I know, but true. Thanks for the tips on changes to the software. Are you saying the timing has changed with no change to the software? If so, the most likley cause would be the spur gear on the quill shaft slipping. It's only pressed on... a roll pin is a good idea on these motors. Set "Timing Lock" to something reasonable (10 degrees, for example) and make absolutley certain actuall timing matches. If it doesn't, it will need to be adjusted either mechanically, or via the software. If adjusting with software, use the parameter "REF Degrees BTDC". Once matched, turn "Timing Lock" off. Quote Link to comment Share on other sites More sharing options...
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