- Feb 11, 2007
- 763
- 3
- 18
Hello all:
Here is the setup:
351W
9.8:1 compression
Trick flow TW heads
.530 lift 230 dur @.050 roller cam
performer rpm air gap manifold
edelbrock 1407 750 vacuum secondary carb
36 degrees total timing (~20) with vacuum advance plugged into manifold vacuum to idle better (no pinging or signs of knocking)
I can get the cruise and WOT tuning correct, but what is wierd is that my wideband O2 shows the motor going dead lean (>15:1) around 1500 rpm at light cruise, just off idle. It happens regardless of how I wanna get in the throttle, so I think I ruled out the accelerator pump. I can creep into the throttle and it still happens around 1500 rpm. After reading the edelbrock manual, it suggested using a stiffer step-up spring. I used the stiffest one and the lean spot is still there. The carb runs like a top everywhere else (way better than my holley 4150), but I would like to attack this one bad spot. What do you think?
Here is the setup:
351W
9.8:1 compression
Trick flow TW heads
.530 lift 230 dur @.050 roller cam
performer rpm air gap manifold
edelbrock 1407 750 vacuum secondary carb
36 degrees total timing (~20) with vacuum advance plugged into manifold vacuum to idle better (no pinging or signs of knocking)
I can get the cruise and WOT tuning correct, but what is wierd is that my wideband O2 shows the motor going dead lean (>15:1) around 1500 rpm at light cruise, just off idle. It happens regardless of how I wanna get in the throttle, so I think I ruled out the accelerator pump. I can creep into the throttle and it still happens around 1500 rpm. After reading the edelbrock manual, it suggested using a stiffer step-up spring. I used the stiffest one and the lean spot is still there. The carb runs like a top everywhere else (way better than my holley 4150), but I would like to attack this one bad spot. What do you think?