Timing Adjustments for H/C
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Timing Adjustments for H/C Last year I put on Patriot Performance Heads.
I've found that at wot around 4700rpm I got a knock in 2nd and 3rd gear. only minor a couple of degrees. My timing is at around 17*. I hear of people running 28*s on the forum, but probably a different setup.
I've got a 160* stat. Compression is around 10.78. AFR is around 12.5:1 at the time it knocks.
Does 17*sound right for the setup?
Looking at the timing graph the more g/cyl you have the less the timing is. I'm around 0.9g/cyl
Just wondered what others peoples timing is on a H/C setup.
I've found that at wot around 4700rpm I got a knock in 2nd and 3rd gear. only minor a couple of degrees. My timing is at around 17*. I hear of people running 28*s on the forum, but probably a different setup.
I've got a 160* stat. Compression is around 10.78. AFR is around 12.5:1 at the time it knocks.
Does 17*sound right for the setup?
Looking at the timing graph the more g/cyl you have the less the timing is. I'm around 0.9g/cyl
Just wondered what others peoples timing is on a H/C setup.
redWS6 00, why is your WB so lean? 17.3:1 should burn you down pretty quick.
.6 is not very much knock, have you tried changing th timing my a degree or two where the knock is at?
.6 is not very much knock, have you tried changing th timing my a degree or two where the knock is at?
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Yep, will knock the timing down a degree or two, but thought it was already pretty low, wasn't too sure how far I should go. I guess I should keep on going until the knock stops, unless its false knock, but as its going it in the same place in two places at the same RPM its probably real knock.
As for the WB, ignore that reading the sensor packed up a couple of days ago. It works fine for about 10seconds after start up, then goes, probably a loose connector, but havn't gotten under the car yet, a lot of hassle since I lowered it.
2000WS6ICK thanks for the log. One thing that different quite a bit is the g/cyl between yours and mine. Its a good comparison though.
Check you knock software. When I ran the 98 knock software that was for my PCM, on the later knock sensors, had to drop timing down to 16* in order to get rid of it. My guess is that it may be your knock software, knock hardware, &/or knock sensitivity settings.
You can also increase the 99+ knock software settings to get rid of false knock.
Check your intake air temps & make sure your fuel line isn't getting cooked by a header. When was the last time you cleaned the injectors? You can still get 12.5:1 & have a couple of partially clogged injectors. How 'bout the fuel filter?
I'm 26* @ WOT & am making just over 400/400 @ the wheels. 417 g/s @ 101kpa. 10.6 SCR, 8.4 DCR, 87% duty cycle on my 30# accels (same as 36# injectors). I know 87% is high, but, it works. Cold air box (just above ambient intake temps). I can't see your file (I have EFI Live). Something is curious about your knock though.
Wait.....I didn't see an injector uprade in your mods. Are you on stock injectors? If so, there is your trouble, 12.5:1 or not. I'd even question the 12.5:1 if your on stock injectors.
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From: England UK
IAT's are pretty cool. 18*C / 68*F.
Fuel rails are warm, but cool enougth to touch.
I'm interested in this Knock settings to reduce false knock. How can you prove a knock is false or not? I'm intersted to learn this, Fuel tuning i can tackle, just unsure on spark advance, other than when knock is seen then reduce timing. I see that under 'Knock Learn' there is 'Total Retard' which is set to 15*. Also many other settings. PE Max Retard is 6* at all RPM's, There is Burst Knock too.
I'll do a search and look into false knock part of it. I see you are running simular RWHP to me, and running 26* timing, so perhaps my knock has been false.
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Just found this log, same IAT's, same INJ, same RPM. No Knock
This log is on the same fuel, 2 days ago. Perhaps this knock was false in my first post. I'll try and move my timing more towards 26* and see if the knock gets worse.
This log is on the same fuel, 2 days ago. Perhaps this knock was false in my first post. I'll try and move my timing more towards 26* and see if the knock gets worse.
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Is your exhaust banging anywhere when you get the knock retard? I think this is the problem I have. I can roll into it and no knock anywhere but if I stand on it when moving slow my Y pipe bangs on the floor and it picks up false knock. It's a very common (and annoying) problem.
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I've disabled the burst knock. As if its looking at difference in the airflow coming in, well its rather erratic according to the MAF, been like that since I descreened it and removed the baffles.
so anyway, was running at around 17* (3000rpm), which peaked at 23* (6200rpm), have flattened it out to 28* across the board, and done a WOT run in 3rd while watching the laptop, good job it was a wide road. The knock didn't exceed 2* and only appeared at 4000rpm, tried it again 28* still remained and no knock this time. So the knock comes and goes, could be the y-pipe.
It pulls far better now will have to see if my 0-100mph time has improved.
Once I get the WB working again I'll tweak a little more, but I'm glad I brought up this thread otherwise I'll still be running on 17* timing.
In the stock timing there is a dip around peak tq, do people just flatten this out, and go for 28* for example across the WOT rpm range, or do some people still keep the dip there?
so anyway, was running at around 17* (3000rpm), which peaked at 23* (6200rpm), have flattened it out to 28* across the board, and done a WOT run in 3rd while watching the laptop, good job it was a wide road. The knock didn't exceed 2* and only appeared at 4000rpm, tried it again 28* still remained and no knock this time. So the knock comes and goes, could be the y-pipe.
It pulls far better now will have to see if my 0-100mph time has improved.
Once I get the WB working again I'll tweak a little more, but I'm glad I brought up this thread otherwise I'll still be running on 17* timing.
In the stock timing there is a dip around peak tq, do people just flatten this out, and go for 28* for example across the WOT rpm range, or do some people still keep the dip there?