Knebel
Senior Member
Whats the general rule when you rev the engine and it pops out the carb and/or stalls?
I recently installed an open spacer and now when i rev the engine a little while its its under 100°, i get this backfire cough through the throttlebody. I could actually make it stall once or twice.
I have a fuel injection that also controlls timing. Don't let that be an issue because it works like the same principle with accelerator shots and so on just on a wider range of adjustments, just works a little different.
Did my carb spacer make the whole thing leaner in the accelerating department? It is a 1/2" open spacer on a dual plane intake. The open spacer is supposed to be better for the EFI to distribute fuel.
I run 18° at idle.
34° wot 3000rpm and 6000rpm (High load high rpm)
1100rpm wot is also 18° (high load low rpm)
39° are cruise values at 3000rpm and 6000rpm (low load high rpm)
22° at 1100 cruise (low load low rpm)
this stuff is based on vacuum/map values so even in free rev, the map value reaches the so called "high load" pretty quickly even though there is no real load.
Anyways, I have the possibility to adjust accelerator pump shots at various temps (20, 65 and 170°).
Is this backfire through the carb rather fuel related or should i look at taking timing out anywhere? Not sure how to approach this since it backfires only under 90-100° through the carb!?
I recently installed an open spacer and now when i rev the engine a little while its its under 100°, i get this backfire cough through the throttlebody. I could actually make it stall once or twice.
I have a fuel injection that also controlls timing. Don't let that be an issue because it works like the same principle with accelerator shots and so on just on a wider range of adjustments, just works a little different.
Did my carb spacer make the whole thing leaner in the accelerating department? It is a 1/2" open spacer on a dual plane intake. The open spacer is supposed to be better for the EFI to distribute fuel.
I run 18° at idle.
34° wot 3000rpm and 6000rpm (High load high rpm)
1100rpm wot is also 18° (high load low rpm)
39° are cruise values at 3000rpm and 6000rpm (low load high rpm)
22° at 1100 cruise (low load low rpm)
this stuff is based on vacuum/map values so even in free rev, the map value reaches the so called "high load" pretty quickly even though there is no real load.
Anyways, I have the possibility to adjust accelerator pump shots at various temps (20, 65 and 170°).
Is this backfire through the carb rather fuel related or should i look at taking timing out anywhere? Not sure how to approach this since it backfires only under 90-100° through the carb!?
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