Originally posted by Frank:
Thanks for the information. Now why don't you pull the rods and dyno? It's not like you can't put them back...
And BTW... 2-4hp from just removing those skinny little butterflies is impressive... I'm surprised you gained any power at all. If you remove the rods, which are much more restrictive, you will probably gain a lot more power.
It will not help you recover the low rpm power, which is more significant than even a 5 hp gain.
I went through the same thing by driving it with the secondaries pinned open and then working normal. No apparent gain up high, but noticeable drop down low. It is why I enlarged my runners, but left the butterflies in. It may leak a tiny bit of air past the butterflies now, but they still operate like normal and more than compensated for the loss of area due to the rod diameter.
