b18c1/p28 (stock gsr map)/crx

I have removed all components that have to do w/ the butterflies in the GSR manifold (except the butterflies themselves). I have plugged up any unused nipples on the manifold.

The car runs great in all gears. The only problem I am having is the car will bogg for a few seconds in first gear a little after vtec crossover then run perfect.

Is this typical when running the stock gsr manifold w/ a p28?