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ijs12fly
06-02-2011, 05:04 PM
Hi,

I am running a Pro Mag 44 (PN 8147) and Pro Mag Tach Converter (PN 8132) with a Big Stuff 3 and Autometer Procomp Playback Tach. During staging I use the BS3 2Step and I am not able to see the actual RPM on our Data Recorder or Tach. The down track data is correct on both. On the 2step the tach shows a much lower RPM around 1100 ish. Our data recorder shows what I will call noise during staging and then the RPM signal is correct once the 2step is released. The BS3 shows the correct info staging and down track. The RPM signal comes from the MSD Tach Conversion box.

The weird part is the tach and data recorder are fine when we are not on the 2step. Is there a known issue and resolution with BS3 2Step and MSD Pro MAG ignition?

Thanks

ijs12fly
06-04-2011, 01:58 PM
Does MSD monitor this and provide support?

msdtech1955
06-06-2011, 12:21 PM
unfortunately, we do not work weekends ....

because of the magneto's firing ..when on the revlimiter ..it will show the cylinders cutting on and off ...this is normal only for the pro mag .

ijs12fly
06-06-2011, 12:35 PM
Thanks for the reply.

So you are saying there is no way to fix this?

msdtech1955
06-06-2011, 01:10 PM
as soon as i can get my race pak file to load up...i'll show you an example or a pro mod on a rev limiter.:thumbup1:

ijs12fly
06-07-2011, 01:10 PM
Was your racepak image going to show me that it looks like noise for you as well? It makes tuning the leave and clutch switch tough because we cant see if the switch is disengaging early or late. Are there any options at all to resolve this?

ijs12fly
06-29-2012, 10:00 PM
So it is a year later and I still have the same problem.

Has MSD identified what is causing my Tach and Data Recorder to not see the actual RPM while on the Two Step? I find it hard to believe that other folks using this configuration are fine with not being able to see the RPM channel while the car transitions from the 2step to Launch.

msdtech1955
07-11-2012, 10:40 AM
heres what the rpm signal on the rev limiter looks like
but keep in mid this is from the tach output and not with inductive led( fiber optic )

only way around it would be to tie a timing computer ( 8168-7730--8973)in line
and use the tach signal off of that for a cleaner signal

using the 8132 ..will continue to give this problem ...
because of the magneto's firing ..when on the revlimiter ..it will show the cylinders cutting on and off ...this is normal only for the pro mag .

2226