If You Think Pole Breathers Are Enough.....
- Thread starter mikesx
- Start date
- Location
- Riverside, CA
It has been my experience that a restrictive air intake system can be
used as a tuning tool for a new set-up because it can prevent a wot
seizure.
Bill M.
used as a tuning tool for a new set-up because it can prevent a wot
seizure.
Bill M.
Are suggesting intentionally choking hood/ pole breathers as a safety? Interesting. The other thing I’m trying to understand goes back to what Waxhead stated, that the carb jetting wouldn’t be rich or lean with a restricted hull air supply as that the carb functions like a regulator and would parcel out fuel and air at the correct ratio, however, a reduced volume. When does rejetting for altitude become necessary? Is it necessary? I would think a restrictive hull air supply would act the same as high altitude. This is all based on hull air ( entire carb), as opposed to a restrictive flame arrestor. What would be your thoughts on that ?
waxhead
wannabe backflipper
- Location
- gold coast
Let me explain it better. The air pressure on the diaphragm is what controls your pop off and fuel flow. If the pressure is reduced all around the carb then the diaphragm will have less pressure pushing on it reducing fuel flow. if the carb was in open air and you then restricted the inlet to the carb it would be a different situation and the mixture would go rich. However in this situation you have the carb in the same low pressure area
- Location
- South Florida
Is there any consensus on largest engine that can be ran with just the rrp pole tubes and not have air flow issues?
What got me thinking/ doubting was the fact my stock FX1 hood had 2 very short completely clear 2.5 tubes for a single carb 61 x. On the Rickter pole you’ve got a much longer run, flexible hoses in a constantly changing state of compression, and one tube ( on my setup) partially restricted by cables. That’s why I checked it. Pole breathers alone wouldn’t of cut it with the 898. If running just pole breathers with anything other than a stock motor, I would think your leaving something on the table. Just my humble opinion
- Location
- Winter Park
I’ve been adding more air thru my hull over the last month with noticeable difference.
For starters I recently got a dasa 1100 in my BAM hull which only has 2.5” pole breathers but obviously more restricted from cables and bends, etc. I wasn’t able to get my dasa 48mm carbs to run perfect, especially the initial hit and it was never consistent. I knew it was carb related but couldn’t tune it out.
I started thinking about air flow and added a 2” thru hull fitting on my dash since my hood can’t allow it. I immediately noticed a difference in performance and was able to tune the carbs perfectly the next day on the water. The ski hit much harder and was much happier. I’ve already ordered another 2” thru hull fitting since I think there is even more air to be had for the motor. Even blipping the throttle on the trailer with my hand over the new hole I can feel a decent rush of air past my fingers. Nothing about mine is scientific but I absolutely know it’s making a significant difference.
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For starters I recently got a dasa 1100 in my BAM hull which only has 2.5” pole breathers but obviously more restricted from cables and bends, etc. I wasn’t able to get my dasa 48mm carbs to run perfect, especially the initial hit and it was never consistent. I knew it was carb related but couldn’t tune it out.
I started thinking about air flow and added a 2” thru hull fitting on my dash since my hood can’t allow it. I immediately noticed a difference in performance and was able to tune the carbs perfectly the next day on the water. The ski hit much harder and was much happier. I’ve already ordered another 2” thru hull fitting since I think there is even more air to be had for the motor. Even blipping the throttle on the trailer with my hand over the new hole I can feel a decent rush of air past my fingers. Nothing about mine is scientific but I absolutely know it’s making a significant difference.
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- Location
- Stouffville, Ontario
I've been running a 836 with novi 48's and TL in my SF with it only vented from the pole. It runs great.
- Location
- South Florida
But could it run better?
My finding as well. +8 mil Lamey with Rrp pipe, RRP poll and don't forget the leaky poll hoses where they pass thru the poll bracket & hull, big leak. Derrick Sr and Eli tune tested it as well...
When I switched to bigger then 900 I added 2 more breathers and just got a manometer to test if poll plus 2 breathers is enough...
Buddy runs dasa +4 1000 cc just thru KP poll tubes in an XFR and it sounds correct with no issues.. Free ride rec ride
For surf I like just the poll breathers to help the ski stay floating longer if it's away from me...
Chase can you post pictures of this?
I'm interested in seeing what people are doing for this, I have a superfreak with an 898 and only the rrp pole breathers, and they take a nasty bend around the pole bolt and pole spring, so there really doesn't seem like much air flow available.
I'm interested in seeing what people are doing for this, I have a superfreak with an 898 and only the rrp pole breathers, and they take a nasty bend around the pole bolt and pole spring, so there really doesn't seem like much air flow available.
- Location
- South Africa
Why doesn't everyone do the hood lifting test with trailer in the water? Quick way to know if your hull breathes enough.
Good point, easier than a manometer and it's free. Well as long as you don't loose your finger
- Location
- South Africa
Haha
That is how I figured out mine was not breathing enough. It had enough vacuum to put red marks on my hand lol.