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Drivetrain => The Dual Quad => Topic started by: dsags on May 26, 2011, 09:12:11 PM

Title: Timing for a Dual Quad 4 Speed
Post by: dsags on May 26, 2011, 09:12:11 PM

The manual says that initial timing for an automatic dual quad should be set at 12 degrees BTDC. As far as I can find there is no reference for a 4 speed. The timing for 4 speed and automatic single four cars are both 2 degrees. So is timing for the 4 speed dual quad also 12 degrees ? Thanks.

Title: Re: Timing for a Dual Quad 4 Speed
Post by: WkillGS on May 27, 2011, 07:51:48 AM

Correct. But only the dual quad distributor should be set at 12 degrees.
If you still are using the 1x4 distributor, it should be set at 2 degrees.

Maximum mechanical advance on either of these should be approx 32 degrees. That setting is more important than the initial timing. If you have too much timing, you could detonate your engine to death!
The stock springs will reach max advance by 3900 rpm. Lighter springs that bring that advance in sooner are a great performance mod.

Title: Re: Timing for a Dual Quad 4 Speed
Post by: dsags on May 27, 2011, 08:34:38 AM

Thanks Walt. I have an 058 distributor in it that Carmen set up so I'll go with the 12 degrees.
Do you think there is any difference in drive ability or performance with either distributor ?

Title: Re: Timing for a Dual Quad 4 Speed
Post by: WkillGS on May 27, 2011, 01:16:48 PM

The Nailheads really like the additional early advance the 2x4 distributors provide! Especially in the light Buicks such as our Skylarks.
Rhett did some performance testing with a new distributor and other tuning. Results are on the board somewhere.