general timing question
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Location: Long Beach, CA
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Car: 1989 IROC-Z Convertible
Engine: 305
Transmission: Art Carr 700-R4
general timing question
This is a very basic question, but here goes. If one were to lower compression from 9.5:1 to around 8.8:1, would the engine require more total timing in order to make compensate? It would seem that this would be necessary but I'm not sure. I have a blown car, and after my recent head swap (the compression was lowered a little due to S/R Torquers need for 350 head gaskets), the custom chip I requested has basically the same ignition timing curve as before and the car seems slightly sluggish.
Spark timing is at 7 Degrees BTDC with EST disconnected, unfortuneately, the computer adds around 15 Degrees at idle. I recall my stock chip adding about 12-14 over the initial 6 Degrees, and what I'd like to do is burn my own PROM with a "broader" timing curve. Basically, setting the distributor to 6 to 8 degrees BTDC at idle, and adding around another 25 degrees for a total of 31 to 33, "all in" by the boost threshold, and then use my 6AL-BTM to pull out about 2 degrees per pound of boost and my FMU to smother detonation. Does this sound right or am I way off base here? Thanks for the input.
Spark timing is at 7 Degrees BTDC with EST disconnected, unfortuneately, the computer adds around 15 Degrees at idle. I recall my stock chip adding about 12-14 over the initial 6 Degrees, and what I'd like to do is burn my own PROM with a "broader" timing curve. Basically, setting the distributor to 6 to 8 degrees BTDC at idle, and adding around another 25 degrees for a total of 31 to 33, "all in" by the boost threshold, and then use my 6AL-BTM to pull out about 2 degrees per pound of boost and my FMU to smother detonation. Does this sound right or am I way off base here? Thanks for the input.
#2
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i have no experience with power adders, but i'd say you're correct. i'd also say you need to learn to burn chips so you can fine tune and make the chip fit your exact engine and application.
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