Modified retard capsule. - Saabnet.com Bulletin Board
Thank you for posting!
The SAAB 900 ignition retard mechanism is a factory set 5 degree reduction from base ignition timing. With a typical 16 DBTDC set base timing, the factory retard mechanism will reduce this to 11 DBTDC.
When under additional charging/boost pressures via APC enhancement, etc., the ignition timing should be brought to 10 DBTDC when under these increased pressures which will provide a more consistent plus higher charge. We will typically recommend fully pressurizing the retard diaphragm when setting the ignition timing to 10 degrees. When relieving this pressure, the base timing would be apparent though the timing light. Modification of the factory ignition retard mechanism stop could take some trial and error but could be 17-16 DBTDC base ignition timing with a retard to 10 DBTDC when under pressure/charge.
We have had customers employing manual boost control on the ignition signal line to allow for some control of ignition retard curve but a majority of ignition impact will come through the change in 1-3 degree change from the factory ignition timing.
Best of luck with your project!
GSK at SWEDISH DYNAMICS, INC.
posted by 32.209.3...
Posts in this Thread:
- Modified retard capsule., Acejed, Wed, 1 Nov 2017 15:53:24
- Modified retard capsule., SWEDISHDYNAMICS, Fri, 3 Nov 2017 13:50:01 <-- Viewing This Message
- Re: Modified retard capsule., thetallguy , Fri, 3 Nov 2017 00:07:17
- Why do you believe a RRFPR is a necessity?, Notnoel , Fri, 3 Nov 2017 11:11:15
- Bleed, turbocon86, Fri, 3 Nov 2017 06:40:55
- Re: Bleed, Saabina, Fri, 3 Nov 2017 07:30:33
- Re: Bleed, thetallguy , Sun, 5 Nov 2017 07:38:55
- Re: Bleed, turbocon86, Fri, 3 Nov 2017 09:31:49
- Alternate approach, Notnoel , Thu, 2 Nov 2017 06:57:36
- I'll take two, please! N/M, Saabina, Wed, 1 Nov 2017 16:12:06
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