Engine will not rev above 5800 indicated on tach

[Westfield 11]

I have 2000 miles on my MegaJolted A-series and I have noticed in the last few weeks that it will not rev above 5800 rpm. I am not sure if this is a new condition as it was a new engine in a newly built kitcar and I have only recently begun to really run it hard. I have been doing carb jetting testing lately and this is when I have noticed the problem. Rev limiter is set to 6500, but the engine acts like it is hitting it early. Could this be a tach issue? Last time I put the wife's laptop on it at idle and indicated 1000 was 1100 on the PC. Would my next step be to hook up the laptop and drive it checking the rpms vs the tach? Are Autometer tachs known for inaccuracy?

BTW, according to the AFR, I have a good 13.3 mixture when it begins to miss at 5800. VR gap is 1mm and sensor mount is very rigid and secure. I changed the sensor plug, but that made no change. Perhaps I should disconnect the Megajolt and just run the EDIS alone? If so do,I just unplug the Megajolt?

[brentp]

You would just unplug the megajolt and the EDIS module would run at 10 degrees BTDC.

you could try bumping up the rev limit to see if it changes anything.

You could also use the software's datalogging feature, and creep up to the redline a bit gradually to see what it does, too

[Westfield 11]

I already upped the revlimit from 6300 to 6800, I will try unplugging the MegaJolt and see if the problem is still there. My next project is to hook up the AFR to the Aux port so I will be doing datalogging for mixture control anyway.