Knock retard when second stage Dry kicks in
Thread Starter
On The Tree
Joined: Aug 2003
Posts: 151
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Knock retard when second stage Dry kicks in Hi guys.
I have a wet 100 shot kicking in at 3000 rpm, and a dry 75 shot coming on at 4200 rpm. I am getting sometimes 2-4 degrees of KR when the second stage kicks in. I have a wideband O2, and it reads a nice fat 11.5-11.8 AFR when the second stage hits, dropping to 11.2 at higher RPMs. I am running 22* timing with NGK tr6 plugs gapped at 0.35.
Any ideas on what could be causing this KR? It immediately decays after coming on, and I never get 2 KRs on the same pull. Does burst knock retard ever kick in based on sudden MAF reading changes (MAF reading jumps obviously when a dry shot hits), or just TPS changes?
Thanks!
I have a wet 100 shot kicking in at 3000 rpm, and a dry 75 shot coming on at 4200 rpm. I am getting sometimes 2-4 degrees of KR when the second stage kicks in. I have a wideband O2, and it reads a nice fat 11.5-11.8 AFR when the second stage hits, dropping to 11.2 at higher RPMs. I am running 22* timing with NGK tr6 plugs gapped at 0.35.
Any ideas on what could be causing this KR? It immediately decays after coming on, and I never get 2 KRs on the same pull. Does burst knock retard ever kick in based on sudden MAF reading changes (MAF reading jumps obviously when a dry shot hits), or just TPS changes?
Thanks!
Thread Starter
On The Tree
Joined: Aug 2003
Posts: 151
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OK, looks like Burst Knock. My grams/cyl load skyrockets when the dry shot hits which triggered the burst retard in both case I saw.
I'l leave the thread up in case anyone else wonder why they are seeing retard on a dry shot with rich AFR and low timing.
I'l leave the thread up in case anyone else wonder why they are seeing retard on a dry shot with rich AFR and low timing.
Thread Starter
On The Tree
Joined: Aug 2003
Posts: 151
Likes: 0
Originally Posted by Chingon
What's burst knock? (Still learning 
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