update on carb prob
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Senior User
Joined: Dec 2001
Posts: 378
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update on carb prob
Well
I finally found the culprit. It was retarded ignition timing. Turns out the timing marks didnt jive on the damper for some odd reason. I went back and retimed it at TDC then advanced 13 degrees. In addition, I removed the powervalve altogher and put a plug in there. To compensate, I jetted from a stock #66 to #74 with the mix screws 2 turns out. Shooter size is a #31 with 50 cc cam in the #1 position. I have the 4 hole aluminum spacer as well. In the vac secondaty housing, i have the BROWN spring. Jetting on the secondary metering block conversion is a 70. All I can say is WOW! NO off idle hesitation and it pulls very strong. I am very pleased at how well this thing is running! Now, I hope my gas mileage improves as well. My faith in Holley's is restored
regards
Ben
I finally found the culprit. It was retarded ignition timing. Turns out the timing marks didnt jive on the damper for some odd reason. I went back and retimed it at TDC then advanced 13 degrees. In addition, I removed the powervalve altogher and put a plug in there. To compensate, I jetted from a stock #66 to #74 with the mix screws 2 turns out. Shooter size is a #31 with 50 cc cam in the #1 position. I have the 4 hole aluminum spacer as well. In the vac secondaty housing, i have the BROWN spring. Jetting on the secondary metering block conversion is a 70. All I can say is WOW! NO off idle hesitation and it pulls very strong. I am very pleased at how well this thing is running! Now, I hope my gas mileage improves as well. My faith in Holley's is restored
regards
Ben
Lead Driver
Joined: Apr 2001
Posts: 6,175
Likes: 21
From: Texas
update on carb prob
So, what do you think got rid of your off-idle stumble?
I have the same problem. Do you think the carb-spacer would help?
I've optimized the timing, tried leaner and richer jet settings on the Ed carb and changed pump shot setting. Still, it stumbles just off idle.
I have the same problem. Do you think the carb-spacer would help?
I've optimized the timing, tried leaner and richer jet settings on the Ed carb and changed pump shot setting. Still, it stumbles just off idle.
Thread Starter
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Senior User
Joined: Dec 2001
Posts: 378
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update on carb prob
gtex
First, try advancing the timing right up until you hear slight pinging and then back it off a bit...before you do ANY carb tuning, Ive found that you need to give the FE some healthy advance.
Next, if you have a holley, i would suggest pulling OUT the power valve and compensate by finding out what the STOCK jetting is and then jet UP 8 sizes. for example, if stock jetting is a 67 with a 6.5 Hg powervalve, pull the powervalve out and jet up to say 74-75 on the primary side.
Third, if you have a holley 600 cm, Ive found that a 31 shooter with a 50cc reo pump works well....a smaller shooter gave me a lean misfire and a larger shooter gave me a rich bog
Fourth, If you still have the metering plate in the secondary side, its OK. I chose to pull mine out and drop in a conversion block and modify with jets like the primary side (my personal preference) However, I dropped in a BROWN spring to keep the secondaries from opening early. I DONT need premature opening bec i do a lot of low speed driving and NOT high RPM use (again personal preference)
Fifth, the spacer was added when i put in the REO pump. It called for a 1/4 inch but i put the 1'' to experiment. The open spacer stole my low end (bad for street) but I found a lil more torque (seat of the pants feel) with the 4-hole. All i can say here is experiment; they are cheap!
Lastly, make sure u have good plugs, wires and NO vacuum leaks--as well as an engine in sound mechanical condition!
Remember, these settings were for a holley 600 cfm 1850 so if you have anything other, you will have to change slightly. I hope this helps you some! Drop me a PM if you have further questions
GOOD LUCK
regards
Ben
First, try advancing the timing right up until you hear slight pinging and then back it off a bit...before you do ANY carb tuning, Ive found that you need to give the FE some healthy advance.
Next, if you have a holley, i would suggest pulling OUT the power valve and compensate by finding out what the STOCK jetting is and then jet UP 8 sizes. for example, if stock jetting is a 67 with a 6.5 Hg powervalve, pull the powervalve out and jet up to say 74-75 on the primary side.
Third, if you have a holley 600 cm, Ive found that a 31 shooter with a 50cc reo pump works well....a smaller shooter gave me a lean misfire and a larger shooter gave me a rich bog
Fourth, If you still have the metering plate in the secondary side, its OK. I chose to pull mine out and drop in a conversion block and modify with jets like the primary side (my personal preference) However, I dropped in a BROWN spring to keep the secondaries from opening early. I DONT need premature opening bec i do a lot of low speed driving and NOT high RPM use (again personal preference)
Fifth, the spacer was added when i put in the REO pump. It called for a 1/4 inch but i put the 1'' to experiment. The open spacer stole my low end (bad for street) but I found a lil more torque (seat of the pants feel) with the 4-hole. All i can say here is experiment; they are cheap!
Lastly, make sure u have good plugs, wires and NO vacuum leaks--as well as an engine in sound mechanical condition!
Remember, these settings were for a holley 600 cfm 1850 so if you have anything other, you will have to change slightly. I hope this helps you some! Drop me a PM if you have further questions
GOOD LUCK
regards
Ben
