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View Full Version : Shift light coming on early?


bsharer
11-19-2006, 07:32 PM
Ive got the 7531.

If I set my shift light to come on at 6000 in 1st, it will come on at 5800, if I set it to come on at 6100 in 2nd, it will come on at 5900.

Any idea what the cause is?

thanks
Bryan

msdtech4
12-07-2006, 08:15 AM
bsharer,

How are you triggering the box? If you are using a distributor is not uncommon to be off some. The unit monitors each trigger point in the distributor and due to gear mesh cam movement etc., anything RPM dependent can activate a little early. Look in the acquisition and when the shift light turns on look at RPM DIFF. If this number is above 200 that is what is happening. This can also happen with some aftermarket ECU's triggering the box via the white wire.

Thanks,

MSD tech4

bsharer
12-13-2006, 08:08 PM
Yes, the rpm diff is above 200 for the majority of a pass. I am using a MSD dist to trigger the box.

Is there anything I can do to help?

msdtech4
12-14-2006, 08:07 AM
bsharer,

If you are using a bronze gear use an over size one to try and take up some of the clearance or the recommended set up for all of the programmable set up's and that would be to put a crank trigger on it. This will give you the most accurate trigger input and will in turn give you the most accurate limiters, shift lights, timing etc.

Thanks,

MSD tech4