Argrarg

Car is a 93 1.6.
Greddy mani/td04/2.5dp/3 exh/fmic/460cc/bkr7e gapped at .025/MSPNP2

First things first. I did set the base timing to 10 degrees advance. Gas is 94 octane from petro-canada.

Im hearing light but consistent knocking from 16-1800rpm to about 2800rpm whenever kpa is around 70-100. Afr is mid 13 to mid 14 in this range. More kpa and less rpm is worse. So I`ve been keeping throttle light and rpm up to avoid it. This is in mundane daily driving situations and i know that low rpm and lots of pedal don't mix.

It isn't audible without det cans but i can hear it loud and clear while wearing them. Det can is hooked up to a cold side motor mount point.

The base megasquirt timing is tame from what i understand so I'm not sure why i would need more retard. Generally, how many degrees should be pulled when you can hear it?

18psi

iTrader: (76)

1st of all, why are you lugging the car at 100kpa at 1600 rpm. Many will knock at such high load at such low rpm. This isn't a turbodiesel

2nd of all you could also have a bad tank of gas.

Does reducing spark in those cells make the knock go away? Just because its a base map doesn't mean its the safest possible map for your car. Its just a starting point.

Argrarg

I wouldn't expect the engine to be happy at 100kpa and 1600 rpm. I meant the lowest kpa reading at the lowest rpm to the highest kpa reading at the highest rpm. 60-70kpa@16-1800rpm to 100kpa@2800rpm.

Not a bad tank. I ran it nearly dry and filled up to be sure of that.

I havent pulled the timing yet. Don't have much experience and not sure how to go about it. Should i pull .5 degree till it goes away? Pull 3-4 and add back 1 degree at a time?

I get that the base map is just a base map but i figured it would be close enough to handle normal driving on 94. Then again I'm obviously a noob....

18psi

iTrader: (76)

pull a couple degrees in the cells it does it and see if it goes away. the base map is fairly conservative so you probably shouldn't pull too much more than that in those regions.

what you really should do though is get a log of the occurance and pinpoint exactly what kpa/spark/fuel/etc is in that specific region.

otherwise we're just guessing here

Argrarg

Sounds like I`ll need to wire in a knock sensor so that i can log it. Kinda hard to pinpoint using det cans on the road which is why im kinda lost.

I appreciate the help.

richyvrlimited

iTrader: (1)

I'd also say that 70-100kpa and 14:1 is a bit on the lean side.

Add fuel

hornetball

iTrader: (4)

Agree. I'd want to see 12.5 to 13:1 anytime above ~80kPa. I think that even the stock ECU goes open loop in this area to richen things up.

albertogti117

iTrader: (2)

Why is it that some people run lean (14.0-15.0) afr targets around 80-100kPa? Not disagreeing with you, I've just seen several maps configured like this and trying to figure out why.

18psi

iTrader: (76)

Because they don't know what they're doing? 15 at 100kpa is not safe

*edit: you said targets. I bet you they aren't actually running that afr, despite targeting it in the afr target table