Interesting Results from Hat change

Ongoing experiment, finally got something close to A-B data. 14-71 SSIF3, BBC at ~32 psi in a 2600 lb door car. 30%OD.

I made an adapter to bolt a 4” throttle body on top. Then switched back to a big and ugly. With the plug looking the same at the 330’ the BAU was 0.14 slower! Haven’t gone past the 330 yet. Car was running mid 4.40s with the 4” butterfly and was lazy out the back in the 1/4. Based on old data I should be able to turn the blower up to 40% and run a low 4.40 with the BAU and probably pick up a few more on the back split in the 1/4. With the 4” throttle body I had 18 degrees out at the hit to go 1.05 but it was all done at 7500. With the BAU it went 1.11 and pulled to 8400 on the shift. No other changes.

I had told some people about this experiment, just thought I would share some results. Makes me wonder why nobody is running adjustable guide vanes in the hat in roots blown promods.