I haven’t messed with the 2 step on mine yet, how much timing are you allowing it to pull? Can it go negative? My previous MSD 2 step would build 5psi at 2500 in neutral so I wouldn’t think the car would be any more difficult to hold back than 0psi at the same rpm.
Not sure how far you can go on MS in the negative but I’m not familiar enough with it. On the Holley stuff with a transbrake and big power we’ve set as low as 7 degrees on the 2step and leave on about 8 psi.