CLASS RACER FORUM - View Single Post - Data Recorder Shows 300 rpm 'droop' After Car Launches???

Michael Compton · 06-14-2012, 05:08 PM

Having ran a car in traditional Super Stock and now SS/BS (comp style), I have encountered the same exact thing that you are describing. According to everyone I talked to, it is almost like the motor takes a big drink of fuel right off the starting line. If you have AFR meters on the car, you can really see the "rich" issue. Some of it I believe was fuel pressure driven and some of it the jetting we were running.

A couple things that did help my current combo in SS/BS were moving the AFR sensors to the headers and not the collectors to get a better reading and increasing the timing on the starting line and pulling it back down track. Seems that the increased timing on the starting line helps burn the fuel a little better when on the tranny brake and within the first 60 feet.

And I think Kyle might be onto something. My issue has almost gone away since changing to the Quickfuel carb and my new A-1 convertor. Maybe it is a combination of the changes I made over the winter but I still think carb and converter helped tremendously.

06-14-2012, 05:08 PM	#4
Michael Compton Member Join Date: Dec 2003 Location: Neosho, MO Posts: 215 Likes: 0 Liked 59 Times in 13 Posts	Re: Data Recorder Shows 300 rpm 'droop' After Car Launches?? Having ran a car in traditional Super Stock and now SS/BS (comp style), I have encountered the same exact thing that you are describing. According to everyone I talked to, it is almost like the motor takes a big drink of fuel right off the starting line. If you have AFR meters on the car, you can really see the "rich" issue. Some of it I believe was fuel pressure driven and some of it the jetting we were running. A couple things that did help my current combo in SS/BS were moving the AFR sensors to the headers and not the collectors to get a better reading and increasing the timing on the starting line and pulling it back down track. Seems that the increased timing on the starting line helps burn the fuel a little better when on the tranny brake and within the first 60 feet. And I think Kyle might be onto something. My issue has almost gone away since changing to the Quickfuel carb and my new A-1 convertor. Maybe it is a combination of the changes I made over the winter but I still think carb and converter helped tremendously.