Odmark91
Well-Known Member
Hello.
The Holley 850 DP on my stroker motor was leaky and old so I decided to swap it out for a new Quick Fuel 850 Brawler race carb (pretty mutch identical to the Holley.
Since the holley was adjusted to the engine on a dyno I figured I would just swap everything in between the carbs, so I did. (Jets, power valve, accelerator pump diaphragms and cam etc).
Installed the carb, set the accelerator pumps so they squirt immediately when the butterflies open.
Started the car and it fired immediately when the float bowls filled up.
Set float levels (middle of sight glass, is this correct?) And set air mixture screws with a vacuum gauge (this was hard though because the cam makes very low vacuum)
And it runs good, but when I floor it from idle it bogs and sometimes backfires through the carb. If I keep my foot down it dies.
If I floor it from just a bit higher rpm, it works perfectly.
What could I be doing wrong? Backfire through carb means lean condition right?
Could I need bigger/to drill the squirter nozzles?
The Holley 850 DP on my stroker motor was leaky and old so I decided to swap it out for a new Quick Fuel 850 Brawler race carb (pretty mutch identical to the Holley.
Since the holley was adjusted to the engine on a dyno I figured I would just swap everything in between the carbs, so I did. (Jets, power valve, accelerator pump diaphragms and cam etc).
Installed the carb, set the accelerator pumps so they squirt immediately when the butterflies open.
Started the car and it fired immediately when the float bowls filled up.
Set float levels (middle of sight glass, is this correct?) And set air mixture screws with a vacuum gauge (this was hard though because the cam makes very low vacuum)
And it runs good, but when I floor it from idle it bogs and sometimes backfires through the carb. If I keep my foot down it dies.
If I floor it from just a bit higher rpm, it works perfectly.
What could I be doing wrong? Backfire through carb means lean condition right?
Could I need bigger/to drill the squirter nozzles?