Wideband AFR tuning a carburetor
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Tuning a carb with an AFR and a vacuum gauge is great. It's quick and easy and it's cool to see how the carb changes really impact the AFR numbers and how a little tuning will go a long way.
The Holley Sniper EFI is a whole different animal. Mine took about 8 hours to install including the Hyperspark distributor new sending unit and fuel pump. Once everything was wired up I turned the key, waited for the pump to prime and it fired right up and settled into a nice high idle. Adjust the idle down, adjust the afr targets and it runs like a dream. I can make impactful changes on the fly. You can then upload to a laptop and using the free software tune every aspect of the fuel and ignition system. It's pretty impressive for the money.
If it can make my crate Goodwrench 350 with the too big cam and stock heads run as well as it does, it should work wonders for a well built engine.
The Holley Sniper EFI is a whole different animal. Mine took about 8 hours to install including the Hyperspark distributor new sending unit and fuel pump. Once everything was wired up I turned the key, waited for the pump to prime and it fired right up and settled into a nice high idle. Adjust the idle down, adjust the afr targets and it runs like a dream. I can make impactful changes on the fly. You can then upload to a laptop and using the free software tune every aspect of the fuel and ignition system. It's pretty impressive for the money.
If it can make my crate Goodwrench 350 with the too big cam and stock heads run as well as it does, it should work wonders for a well built engine.
I have the Fast EFI but I would go with the Holley EFI if I was going to do it again....
is the sweet stache included?
tape the phone to your head....or get one of these...
Update: The 850 vacuum secondary runs well, cruises well, and AFR is good everywhere. It has the tiniest of hesitations at 1900rpm for some reason. I have tried everything and I believe that it is the rpm where the distributor springs start moving.
The QFT 1050 annular carb runs way better. All kidding aside it has to be 30 or 40hp better. AFR was 11.5-12.0 rich at idle and I couldn't lean it out enough. I bought jet blanks and pin drilled them smaller and now it idles well at 13.5-14.0 and 900rpm. I removed the rear power valve and jetted the primary down and secondary up and will tune in the cruise and WOT this weekend. The AFR gauge has been well worth the money and fun. Even though both carbs ran ok, the gauge proves that they were way off of optimum just about everywhere prior to tuning.
The QFT 1050 annular carb runs way better. All kidding aside it has to be 30 or 40hp better. AFR was 11.5-12.0 rich at idle and I couldn't lean it out enough. I bought jet blanks and pin drilled them smaller and now it idles well at 13.5-14.0 and 900rpm. I removed the rear power valve and jetted the primary down and secondary up and will tune in the cruise and WOT this weekend. The AFR gauge has been well worth the money and fun. Even though both carbs ran ok, the gauge proves that they were way off of optimum just about everywhere prior to tuning.
No they aren’t
I drilled the low speed air bleeds (0.085”) and drilled new idle feed restrictors (0.035”) to lean out the idle. The originals were 0.078” and 0.038”. Worked out perfectly. I still have some fine tuning to do on cruise and WOT
I drilled the low speed air bleeds (0.085”) and drilled new idle feed restrictors (0.035”) to lean out the idle. The originals were 0.078” and 0.038”. Worked out perfectly. I still have some fine tuning to do on cruise and WOT
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