Worse with 95 octane, improved but still there with Shell V-Power.
Timing is set at 8 BTDC.
Do I need to retard even further or is there another cause? Like there is a blow in the downpipe somewhere.
I can get the car to pink under strong acceleration in 2nd gear. Even 1st sometimes......
Any advice welcome!
Mark.
Pesky detonation
There are several causes to pinking :
1) too far advanced timing
2) lean fuel mixture (air leaks on carb/manifold)
3) engine running too hot (air locks in cylinder head)
4) wrong octane rating (or crap fuel !)
The standard for all BX engines should be a static timing advance of 10 BTDC - vacuum advancing disconnected - running on 97 octane fuel.
This should be modified to 8 BTDC running 95UNL.
Remember you can only check the timing using a stroposcopic light.
1) too far advanced timing
2) lean fuel mixture (air leaks on carb/manifold)
3) engine running too hot (air locks in cylinder head)
4) wrong octane rating (or crap fuel !)
The standard for all BX engines should be a static timing advance of 10 BTDC - vacuum advancing disconnected - running on 97 octane fuel.
This should be modified to 8 BTDC running 95UNL.
Remember you can only check the timing using a stroposcopic light.
C U / Anders - '90red16riBreak - '91GrisDolment16meteor - Project'88red19trsBreak
dead cars : '89white 16RS - '89antrasitTRDturboEst - '90white19triBreak
dead cars : '89white 16RS - '89antrasitTRDturboEst - '90white19triBreak
- mnde
- Meteor Man
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I should have added that I have already carried out a stroboscopic timing check, yes with vacuum advance disconnected - I have read the instructions in Haynes etc. - it was around 10-12 BTDC, I set it to 8 BTDC. Yet it still pinks with 95UL and doesn't disappear 100% even when using Shell V-Power, which I believe to be 98-99 octane.
Re. lean fuel mixture, I guess I'll have to get out the WD40 and spray all around the carb joints with the engine running - not sure what I can do to test the manifold. I have a Gunsons Colortune, but the standard size is to fit 14mm sparkplug sockets - so I have to buy a separate adaptor before I can use it on my BX
Mark.
Re. lean fuel mixture, I guess I'll have to get out the WD40 and spray all around the carb joints with the engine running - not sure what I can do to test the manifold. I have a Gunsons Colortune, but the standard size is to fit 14mm sparkplug sockets - so I have to buy a separate adaptor before I can use it on my BX
Mark.