pcmhacking.net

What’s everyones experience with Holden 304 and false knock counts?

Interestingly these 4 engine were running the enhanced code and tune done by The1. It was I who nailed it down to the fuel pump after actually seen pics of the pistons, I knew it was detonation right away. Otherwise engines catastrophically failing pretty much after installing them a non tech savy person would assume the 2nd hand engines were duds as this guy did, they died that fast you would thing that was the case, but by the 4th one nah something fundamental was wrong.

Fuel pump as also dismissed as the words went "I got a brand new pump though" which even I though yeah ok not likely the issue but when I asked what brand, bingo! That fixed the issue straight away. But anyway it just shows you how fragile the ecotec pistons are and how not reliant the knock retard is because if it really did retard it down -9º iirc it would of been fine as it would only be running low teens of ºs max timing which basically in my experience almost stalls the engine lol.

Unlike the ecotec the buick can tolerate a lot of knock. My old VP engine use to severely knock for some reason, only has 24º max at WOT that it would turn heads on the road as I passed people, only did it on 35c air temp days going up hill even with a cold engine, it also ran pig rich on fueling too, I suspect carbon deposits or something or maybe in combo with bad 98 fuel which is quite possible as I have had lots of issues with Shell fuel and that is when I had a Shell only company fuel card. Of course it did not detect and retard at all. I checked with a bores with a bore scope and surprisingly I found 0 damage, lots of black soot though lol.

brindo wrote:What’s everyones experience with Holden 304 and false knock counts?

Well they don't have factory knock hardware unless its a HSV. As for knock, they are easier to make knock than a buick v6 and they retain the sound well so you can't hear is outside the engine much if any but with knock ears prepare to go deaf when it happens. It bloody loud! like cap guns going off in a drain pipe.

Didn’t really want to turn knock control off. I might try fitting a second order sensor to one bank and than swap over to the other side while getting plenty of logs and inducing some light knock, see what happens. I’ve got the other vy there still running a flash pcm I can test on. With only a max of 10deg of timing into boost at 11.8afr on e85 I shouldn’t be getting knock

10 degrees at max torque is still a lot of timing on an ecotec lots of people out there running 0-2 degrees as boost hits the fast burn head chambers arnt conducive to lots of timing designed to burn fast and as complete as possible to pass emissions

The sensor will need to be the correct resistance or the ecu will pack a fit and you'll probably need 2 cause they are wired in parrelell if I remember right not separate feeds to different ecu pins

I’ve leaned the afr’s out to 12.5 all the way to 13.0 and get less knock and pick up heaps of power. I thought maybe I was getting wb offset but even after going over all that afr’s are still same.

I just seem to pick up knock no matter what I do. I’ll need to and plan to dig deeper but it’s apparent I can’t trust the knock control. If I was getting real knock there’s no way the motor would still be going strong

Just get knock ears, disable the ECU knock side of things and call it done. You won't regret it and your engines from now one will thank you for it.

Sounds like spark is struggling and its misfiring if leaning it out fixed it I wouldn't go any leaner than 12:1 I stick around 11.7 its not worth the engine parts to lean it out for 4or5 hp