its pinging under acceleration at 36.. I set it using a dial back light set to 36.. advance plugged and I put a softer set of advance springs in... keep moving it back or something wrong??
Are you setting it at Idle, 3000rpm, 4000rpm? Why softer springs? If you have 36 at Idle, and add 20 mechanical and another 20+ vacuum you end up with a lot. Even with low vacuum on acceleration you are looking at close to 60 degrees once the mechanical comes in.
I used softer springs on my vette and it made a huge difference...I was following the "timing by lars" papers.... I switched to the medium springs that came with the curve kit... revved up the rpm to 2500 and set my timing gun to 36... it seems ALOT better.. I'm headed out for a ride now... its on empty so ill be filling up with 91 oct. I'm using ac delco rt44s...???
still pinging under hard acceleration... wouldn't start back up after I shut it off.. I'm gonna let it cool and start dialing it back some... it sounded fine under cruising speed.. but when I step on it its knocking...
this is only happening when the car heats up... I took the car out this morning and it ran perfect.. after about 5 minutes of driving it starts pinging when I step on it..
It's common to have more detonation when hot. What temp is your car running? Just keep backing off the timing until you have no detonation on hard pulls. When you rev engine up does the timing quit advancing at 2500 rpm? I would think that is a bit soon for full mechanical, I have mine full mechanical at 3000-32000. You may want to try some stiffer springs to get the full mechanical all in a little later.I would also think 36 degrees total initial and mechanical is too much as well. Somewhere around 30-32, maybe a bit lower if your getting detonation from heat.
Try this... Disconnect and plug your vacuum advance hose. Set your initial at idle timing to 11 - 14 degrees so it starts and idles well. Take it out on a back road and accelerate in second gear. If you have no detonation up the timing a couple of degrees. Keep accelerating and upping the timing two degrees at a time until you experience detonation then back off two degrees. That point just below the detonation setting is optimum.
Your hard starting when hot problem could be due to too much initial timing. Heat makes a huge difference and you'll need a lower initial timing to start when hot. The good thing about using the vacuum advance on manifold pressure is as soon as the engine starts with a lower setting the vacuum advance ups the setting for a cooler and smoother idle.
I just bought new gauges and hooked them up today.. the temp gauge reads 230 in no time.... I shut it off and it shot up past that.... I wasn't thinking it was getting hot... new aluminum radiator.. 2 electric fans.. flow kooler water pump.... the fans come on at 190 or so... but the temp keeps rising... holy smokes!!
+1 On the earlier posts.. If anything a less aggressive distributor curve is needed. Definitely go to heavier springs. And, is the vac line attached to ported or full vacuum? The factory uses ported, but some feel it's better to run full vac.
Cooling; is there hot coolant flowing through the top hose at 190? If not, perhaps the thermostat is not fully opening?
+1 On the earlier posts.. If anything a less aggressive distributor curve is needed. Definitely go to heavier springs. And, is the vac line attached to ported or full vacuum? The factory uses ported, but some feel it's better to run full vac.
Cooling; is there hot coolant flowing through the top hose at 190? If not, perhaps the thermostat is not fully opening?
the vac line is to the carb... I may tru to move it to the intake just for the heck of it.... I'm gonna put the fan back on and remove the electric fans just as a test... I will check the thermostat just to be sure...
+1 On the earlier posts.. If anything a less aggressive distributor curve is needed. Definitely go to heavier springs. And, is the vac line attached to ported or full vacuum? The factory uses ported, but some feel it's better to run full vac.
Cooling; is there hot coolant flowing through the top hose at 190? If not, perhaps the thermostat is not fully opening?
the vac line is to the carb... I may tru to move it to the intake just for the heck of it.... I'm gonna put the fan back on and remove the electric fans just as a test... I will check the thermostat just to be sure...
I don't recall what carb you have, but on Q-Jets the ported vac is on the left [drivers side]. If you have a vacuum gauge, the ported port should be easy to find. The issue with manifold vac is it is at full vac most of the time unless at WOT.
I got the pinging under control. I tried some octane boost and I added a fan shroud and stronger fans. It was 90 today and went for a nice ride cruising and it was 195 until I got on it a few times. Never got over 210 though. I think the engine getting hot and bad gas was the issue.