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Technical => Spud Miller's Cave => Topic started by: captndiet on January 16, 2014, 01:16:35 PM

Title: Mag Advance/Retard Set-up
Post by: captndiet on January 16, 2014, 01:16:35 PM

Spud

Question on your Mag Advance/Retard set-up.

When you activate it, does it hit all at once or do you have an air bleed to bring it in slowly?

Jeff

Title: Re: Mag Advance/Retard Set-up
Post by: Spud Miller on January 16, 2014, 01:30:25 PM

 Hi Jeff,

 There is a speed control on forward and reverse both...so you can adjust the speed separately for advance and retard. You can have it slam instantly or take forever.

 Lots of guys run it with a fairly slow advance rate to bring the timing in over a second or two at the beginning of a run. Then they have retard setup rapid so when they see the 1000' mark, they push a steering wheel button to have it slam back at the top end.

 Spud

Title: Re: Mag Advance/Retard Set-up
Post by: BK on January 16, 2014, 03:58:27 PM

How much of a change might be seen when you retard the timing. How much timing would normally be taken out.

Title: Re: Mag Advance/Retard Set-up
Post by: captndiet on January 16, 2014, 04:13:04 PM

Spud

Since I will be starting from scratch, in your opinion, which of the three mag drive couplers seems to be the best?

Jeff

Title: Re: Mag Advance/Retard Set-up
Post by: Spud Miller on January 16, 2014, 05:31:43 PM

 

Quote

How much of a change might be seen when you retard the timing. How much timing would normally be taken out.

Cars running methanol tend to fiddle with 5 to 8 degrees of timing added/removed. Guys running high percentages of nitro will play with as much as 20 degrees or so of change.

 On my setup, I add 17 degrees from the hit of the throttle over about the first 1 - 2 seconds. I leave at 45 degrees so I don't blow the tires off (and the motor starts easy). I end up at 62 degrees. I haven't played much with taking the timing away again at the top end. I really think that's more for supercharged methanol.

 Spud

Title: Re: Mag Advance/Retard Set-up
Post by: Spud Miller on January 16, 2014, 05:36:51 PM

Quote

Since I will be starting from scratch, in your opinion, which of the three mag drive couplers seems to be the best?

The cross is the most popular and the majority of drives are setup for that. The Rotex and Lovejoy are great, but those seem to be something only RCD likes to do. We make crosses (aluminum only), Rotex, Lovejoy and the 4-pin setups here. We also have a nice female cross piece (steel or aluminum) that can be used for driving if you're building something yourself.

 Spud