2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

timing question

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Old Jul 19, 2002 | 07:16 AM
  #1  
GLHS's Avatar
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From: Seminole, Florida
timing question

I have a question about timing a 88 N/A.

I have been running my car with trailing on the yellow and leading on the red mark.

I wanted to advance the timing and this one guy who runs SCCA RX7s told me to put the leading back to the mark for trailing.

He also said something about taking the cover off the distributor and doing even more timing, but I really got lost, cause I didn't take notes.

Has anyone done any timing on thier cars?:
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Old Jul 19, 2002 | 01:04 PM
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From: Atlanta, GA
distributor is only for the 1st gen rx-7s. I believe there is a timing screw on the 2nd gens but I'm not sure where. Someone else may chime in on this.

Note timing should ONLY be adjusted for tuneups or if your getting knocking after a tuneup.
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Old Jul 19, 2002 | 01:21 PM
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I only used the word distributor, its acutally crank sensor.

I was told that advancing the timing by 22 degrees, is ideal for maximum power from a N/A.

He basically told me to move the leading up to the mark for the trailing, and he also said to do this on the second rotor wires, not the first ones.
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Old Aug 21, 2002 | 10:35 AM
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From: not in winterpeg anymore
I would like to know this answer as well
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Old Aug 21, 2002 | 01:37 PM
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From: Prov RI
Set the leading and don't worry about the trailing. Just make sure the trailing plugs are working.
Try running the engine with no trailing and than no leading. You will see what I mean.

I read somewhere that one of the NA ECU chip tuners bumped timing almost 20 degrees but cut it back as the engine approached redline.

The factory settings are 5L/20T degrees ATDC.
The 5 degree mark is yellow.
The 20 degree mark is red. Setting the Leading to the Trailing gives 15 degrees advance.

Increasing timing increases heat and risk of detonation. Super unleaded is recommended and make sure that your cooling system is working. Other recommendations would be to eliminate the coolant flow through the TB and to use a cold air intake.

I can't see how you are running the trailing on the yellow and leading on the red. When I checked my timing, both were perfect(not bad for 85k miles). When I advanced my timing, I set the Leading advanced and the Trailing was nowhere to be found. Maybe I'll go check again when I have time. I'll have to clean/highlight the marks.

And, I don't know why someone would say to use the second rotor wires(T2/L2). Maybe they meant the bottom L1 wire.
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Old Aug 23, 2002 | 08:40 AM
  #6  
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From: Prov RI
My mistake. Got ATDC and BTDC screwed up.
Clockwise with the CAS=advance=higher idle=more power+mpg(usually)
Idle needs to be adjusted for accuracy's sake between changes.

It stumps me that Mazda set initial timing at ATDC.
And, I wasn't thinking straight or I wasn't thinking backwards.

Mazda's spec is late at -5/-20 BTDC.
Moving the trailing to the leading gives 15 degrees advance. And, if I'm thinking straight, 15 degrees advance changes timing from the 5 ATDC to the unmarked 10 BTDC.

Make sure the pulley is highlighted. Clean the crud off. Also, it is easier to use a timing light with an advance dial. Because you are a racer, it would be beneficial to set "max advance" for max power on a dyno and not even worry about the "idle timing".

And, if you are ambitious, you could remove the pulley and make additional marks with white-out or a yellow paint pen. If you don't have a protractor, you can use ford/chevy/dodge timing tape. Just try to match the diameter of the T-tape's spec as close as possible to the Rx's pulley diameter.

Heres food for thought:
If the rotor spins at 1/3 E-shaft speed, then timing changes aren't as aggressive as with a "boinger".
A pseudo comparison would be 15 degrees change in a rotary would yield a pseudo equivalent 5 (15/3) degree change in a boinger.
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