tip in lean spikes? are you suggesting a stumble due to lack of pump shot on acceleration? i have had similar issue. partly due to 2.00 inch TB can flow a lot of air immediately and the AE cannot keep up. IMO! how much additional AE are you giving it? I added 200% accross the board and am at about 2600usec on AE/TPS and 2000 AE/MAP. what are your readings on TPS and MAP? i was told to give more down low say at bottom hald of rpms but i did same % across board. that may have been mistake. I possibly shopuld have done much more at lower rpms. if you have crossfire manifold i think it will do a better job on AE that the set up i ran. IIf you VE's are in order and not lean then AE may help. i was told spark can also be looked at but i have not mad any changed there other than to reduce a KC at 20-30 map and 2400-2800 rpms. check your TPS setting and no vac leaks.