Help, only dynoing 300RWHP

[Locobob]

Originally Posted by Pete

Peaks at 5600
Some details please.

Pete

My first porting job so the runners were a bit more conservative than what I do now but it's mainly the lack of headers causing the early hp peak. Might also be breaking up a bit at the top cause of lack of tuning - you can see some "seismic" activity starting at around 5600rpm. Car was a pretty stock 350cid with Power Effects exhaust.

Back to the comparison: You can see on my graph the car is making 200hp around 3300rpm vs your 165ish - that says a lot about the nature of your issue - look at Nacho's dyno and you'll see the same trend = Your problem is across the board. Secondary issue.... good possibility.