Disappointed with my engine

Thanks for your input. A Slingshot is nothing like your heavy door cars to run. Time and tine again it's been shown headers make no difference to ET over Zoomies. For a car that's just for fun like mine, converter selection isn't as critical as it is with your heavy tin tops - we just don't have the mass to shift off the line and we don't have suspension and stuff to think about - we tune the lauch with tyre pressures wheelie bar adjustment and the addition of some weight on the nose depending on the track. In the early 1980's I ran one of the popular at that time tall econo drsgster type scoops which was sealed tight and picked up three tenths and 6 mph but the suggested pressurization of the vents/ fuel bowls is something I'll look further into. Wonder what the blow through turbo guys do ??? Moving to Chrysler has been a learning experience - I've learnt the hard way that the oiling system needs a bit of thought to keep bearings and crank in nice shape. Pity about the heads. I do get it - they're like a gaint kink in the garden hose.
Thanks for your thoughts
Cheers