85 corvete timing
Safety Car
Joined: Aug 2009
Posts: 3,751
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From: Melbourne, Victoria, Australia
6 degrees remember to disconnect the set timing ESC wire to stop ecm changing advance while setting it.
One more thing, the balancer outer ring is known to slip.
Usually a good idea to check no1 piston is at tdc when timing mark is at tdc, if the outer balancer ring slips it usually goes backward to timing cover.
Team Owner
Joined: Sep 2001
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
6 is the base timing setting, but I'd run 8. I always ran 8 on my 86. Always on 87 octane as well. Never got knock.
Last edited by vader86; Jul 18, 2018 at 06:06 PM.
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Joined: May 2001
Posts: 4,757
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From: Fairfax Virginia
If you do follow the advice of some and run 8 degrees instead of 6 then be sure that your knock sensor/s are working properly.
By going up on the timing you MIGHT loose the ability to run 87 octane fuels. More timing would make the car want more octane, if that is not a problem then go for it.
If your knock sensors are out of wack you might hurt the engine with the detonation that can occur.
I have a 1968 BB C3 for going fast, my 1988 is a cruising car and I am satisfied getting 30 mpg driving it easily. I also use 87 octane and have no pinging or knocking at all.
I test my knock sensors every year or two. I bought a kit from Mid-America which had like 8 different testing rigs that plug and play. No modifying or splicing just put the tester in between the sensor and the harness and see in real time what it is sending the engine. It was the best $100 I spent on my C4. I have helped others set up their engine quickly with these tools. You can tap a ratchet on the block and you see the response from the knock sensor.
Good luck with your Corvette!
By going up on the timing you MIGHT loose the ability to run 87 octane fuels. More timing would make the car want more octane, if that is not a problem then go for it.
If your knock sensors are out of wack you might hurt the engine with the detonation that can occur.
I have a 1968 BB C3 for going fast, my 1988 is a cruising car and I am satisfied getting 30 mpg driving it easily. I also use 87 octane and have no pinging or knocking at all.
I test my knock sensors every year or two. I bought a kit from Mid-America which had like 8 different testing rigs that plug and play. No modifying or splicing just put the tester in between the sensor and the harness and see in real time what it is sending the engine. It was the best $100 I spent on my C4. I have helped others set up their engine quickly with these tools. You can tap a ratchet on the block and you see the response from the knock sensor.
Good luck with your Corvette!
