TTI Small Block Shorty Header Install

Sorry Ogre, I have no data. Was there a improvement ? Yes. Being that it was a stock 273 with just a 4 bbl added.
To me, and this is just my opinion, Shorty's are sold for the ease of installation not for major performance gains.
In my case a bit better than cast 2 bbl manifolds.
It has been proven that long tubes perform better.For sure if the engine is large cube, high horsepower.