Bonneville America Forums Forums Technical Forums Performance Mods Performance gains from various intake mods?

So it turns out with my new ebay pipes (2 baffels drilled out and 2 holes drilled in 3rd baffle) I'm probably going to have to rejet (thanks to all, especially Dog for their input) so while I'm at it I'm thinking about modifying the intake side of the equation as well.

In looking at my choices it looks like I've got 3 basic options:

1) Freak or Ghetto freak
2) Drill airbox & desnorkle with stock air filter
3) Drill airbox $ desnorkle with K&N or Uni filter

I'm really leaning away from the freak or ghetto freak because I don't want to take the bike apart that much right now (I just got it back together!) but could be persuaded if the performance gains are significantly greater than the other methods.

I like the drilled airbox with stock air filter because it is totally 100% free since I am rejetting anyway, but will I see any gains at all with the stock filter? Also if I went this way and decided to switch to a K&N in 10K miles when I need a new filter anyway, could I keep the same jetting or would I need to rejet again?

I am trying to balance performance gains with money and time - the eternal stuggle

if you have the money go with the freak, everythign you need is there and it is staright forward install

Frank

I haven't gotten the budget to go for the freak, yet, but I think it offers the best intake application. I did put a K&N in the desnorkled airbox and the difference was readily apparent.

I checked Pat's jet calculator and it says that I could use the same jets (132s) whether I use a paper filter or a K&N. Would this suggest that the performance would be similar with either?

Wow, I see with the Freak I would need to go up to 154 jets - that seems like a huge jump!

big difference with the freak. a clean paper filter in our airbox works fine. K&N wont offer that much of a gain. better if you dont want to buy new filters imho

Frank

Hmm... the more I read about people's experience with the freak, the more I am being tempted... If I'm going to pull the carbs and mod the bike I might as well get all the surgery done at once.

So with the Freak and pipes with 2 baffles out and 2 holes drilled in the 3rd baffle, does 150 mains, 45 pilots and TBS needles with 1 shim sound right? Or just go with 155 mains and leave the needle stock and pilots at 42?

with the 155, stock needles and 42, you have a good chance of being lean somewhere and would likely have popping on deceleration.

In very a simple nutshell, the pilots are your idle circuit, the needles handle mid throttle, and mains handle WOT. Of course, there is a lot of overlap of these components in the fuel circuit, but this should help you understand. Someone will likely post a pic of the fuel curve for you...

Using the shims takes out the flat spot in the midrange, if you have it. Some do, some don't.

The FREAK is easy, cheap power...

The first scenario sounds most realistic, however I would guess rich with the 3rd baffle still in.

You wil need to get the "D" tool as well to set the idle mixture screws, and wen you are done, balance the carbs. Also, set rid of the AI.

I have the same setup your are considering and she runs like bat of ******.

155's, 45's, TBS needles, no shims, freak, NKG Iridium plugs, stock pipes de-baffled except for the reducer cone, 3 turns on the screws.

My plugs are a perfect tan, I have no decel pop, I replaced the D srews with Brents thumb screws well worth the few bucks. I'm getting about 45 miles to a gallon of gas.

I love this setup I run a 18 tooth primary gear and I have low mid and high end acceleration.