Ignition timing?
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Instructor
Joined: Aug 2003
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From: Soddy Daisy TN
Ignition timing?
I took my 85 Coupe to a shop and had it tested on a dyno. The results were suprising! Peak HP was 193 @4500 RPM. Max torque was 230 @ 4500 RPM then it just fell off. The guys who tested the car said it was one of the faster cars they had tested as far as how quickly it accelerated on the dyno. We discovered it had a 373 gear installed. Top speed was only about 100 mph but it sure got there quick. I was stunned! Factory specs show 230 HP- 330 LB FT tourque. I expected to have at least those numbers since the car has no cats and Flowmasters, the Accel dist and K&N air filter. Then we noticed that the distributors (Accel HEI Super Coil) number one plug wire was not pointing toward no. one cylinder. When I took the car home and put a timing light on it the timing mark was not even on the indicator. It was about a half an inch before it. That blew my mind!!! :eek: So here is my question(s). What is the ignition timing supposed to be for my engine,(L98)? Will my distributor only insert 2 ways into the oil pump shaft, (180 degrees out)? Can I move my spark plug wires over one position all the way around the distributor? Do I need to pull the distributor and turn it?
I would appreciate any advise from the experts. Thanks, Troy
I would appreciate any advise from the experts. Thanks, Troy
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Joined: Sep 2000
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From: The Top of Utah
Re: Ignition timing? (drumboytroy)
If your timing were 180* off it wouldn't run. Your timing can't be TOO far off to produce those dyno numbers. Disconnect the EST wire to the distributor and check the timing again. The spec is 6* BTDC. I run mine at 14* BTDC. The oil pump drive rotates. The distributor may be installed anywhere a tooth on the dist will engage the cam, this means virtually anywhere, 360*. Where ever you want the distributor to point, just make sure that the #1 plug wire gets installed where the rotor points with the #1 piston at TDC on the compression stroke. Those are nice REAR wheel numbers conpared to FLYWHEEL ratings. Good luck, and...
RACE ON!!!
RACE ON!!!
Thread Starter
Instructor
Joined: Aug 2003
Posts: 235
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From: Soddy Daisy TN
Re: Ignition timing? (CFI-EFI)
Hey CFI-EFI,
Disconnected the EST wire and re-checked timing...8Degrees BTDC. So it is pretty close. I guess I just expected to see higher numbers at the dyno. If I understand correctly there is about 18% loss of HP from flywheel to rear wheel. Is that correct? The car is pretty quick.....but you know how we are, we're never satisfied. Have a good day! :seeya
Disconnected the EST wire and re-checked timing...8Degrees BTDC. So it is pretty close. I guess I just expected to see higher numbers at the dyno. If I understand correctly there is about 18% loss of HP from flywheel to rear wheel. Is that correct? The car is pretty quick.....but you know how we are, we're never satisfied. Have a good day! :seeya
