Where should AFR readings be for MPI 509
#12
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Joined: Jun 2011
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Assuming a MP injector set up and balanced/flowed injectors all cylinders should be close....again assuming....
#15
Vacuum and how it applies: each 10 map or kpa is 3.3" of vacuum. So cruising "easy" if your at 70 map, its about 10" of vacuum, you can tune the motor around 13.5 in the 1600 to 2800 range IF your at 70 map, ie, low load, when your in the 80 map range, 12.8 to 13.2 or so is ususlly fine up to about 3400/3600. When you start hitting 90 map, i like to see mid 12's, when you start getting into 95+map AND near the tq peak, usually 3800 to 4200 or slightly higher, mid 12's , even 12.2 to 12.5 once your hitting 4400/4600 on up.
i give the idle whatever it likes, ive seen quite a few motors that didnt like 13+to 14 at idle even though thats what you would think of as "normal". You still need to take a look at the plugs too if you choose to lean out around 2800 to 3400, especially 7/8
i give the idle whatever it likes, ive seen quite a few motors that didnt like 13+to 14 at idle even though thats what you would think of as "normal". You still need to take a look at the plugs too if you choose to lean out around 2800 to 3400, especially 7/8
#16
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Joined: Nov 2009
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From: KY
Vacuum and how it applies: each 10 map or kpa is 3.3" of vacuum. So cruising "easy" if your at 70 map, its about 10" of vacuum, you can tune the motor around 13.5 in the 1600 to 2800 range IF your at 70 map, ie, low load, when your in the 80 map range, 12.8 to 13.2 or so is ususlly fine up to about 3400/3600. When you start hitting 90 map, i like to see mid 12's, when you start getting into 95+map AND near the tq peak, usually 3800 to 4200 or slightly higher, mid 12's , even 12.2 to 12.5 once your hitting 4400/4600 on up.
i give the idle whatever it likes, ive seen quite a few motors that didnt like 13+to 14 at idle even though thats what you would think of as "normal". You still need to take a look at the plugs too if you choose to lean out around 2800 to 3400, especially 7/8
i give the idle whatever it likes, ive seen quite a few motors that didnt like 13+to 14 at idle even though thats what you would think of as "normal". You still need to take a look at the plugs too if you choose to lean out around 2800 to 3400, especially 7/8
#20
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Joined: Nov 2009
Posts: 4,198
Likes: 500
From: KY
Thanks, Eddie removed the center mesh out of the stock arrestor, so all I have is the double screen, and its plenty clean, and can see clear thru the other side
If I took a pic above the FR you could see thru, the angle is misleading, and thanks for the thought
If I took a pic above the FR you could see thru, the angle is misleading, and thanks for the thought



