Mast M90 w 6l80

[mikekirby1]

I bought the mast l92 hp package with their cam and ecm tuned for that cam. Planned to run the 6l80 behind it as I understood that the M90 could send the proper signals to run it. Everything was going smoothly until I got to the wiring harness and it didn't have a plug to go to the transmission. Just a plug near the engine for the addition. I emailed mast and asked them if there was a harness I need to buy from them. They said to contact zero gravity and they would get me sorted out for the 6l80 with their ecm. I called them and they said I need a harness along with ANOTHER controller since mast does not send the proper signals and this would cost $1000. The cost bothers me a little but worse than that is now I will have another controller. Another point of failure to possibly leave me stranded. I'm wondering if I should just sell the mast kit and go with a speartech harness and use the stock ecm. Keep it standard with gm parts. What would you do?? Any suggestions?

[dhutton]

If you go with Speartech you will lose your MAST tune. On the other hand Speartech is one of the best for 6L80E packages but they are going to need to retune the controller in your 6L80E.

What new controller are they telling you to get?

Don

[mikekirby1]

I would just send them the original ecm, tcm and harness and let them rework it then have it dyno tuned after I got it running. Seems like a lot to get around using the controller. I guess Ill have to bite the bullet and just buy the transmission controller. Im sick of drilling holes for wire harnesses and mounting computers.