Janne339
TY 4 Stroke Junkie
How looks the throttle body assembly and configuration on Sidewinder?
Haven't looked closely but will for sure.
Those vacuum ports could lead to after or before throttle plate also. Didn't check. And they are definitely in diff position compared to Nytro in pic.
Bump
DT
Extreme
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- Location
- Michigan, Flint area
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- Snowmobile
- 2006 Attak
1015 Viper
Sorry bud, I haven't got that far yet. Not as fast as you
Janne339
TY 4 Stroke Junkie
From a 2008 Nytro service manual.
DT
Extreme
- Joined
- Dec 26, 2011
- Messages
- 107
- Location
- Michigan, Flint area
- Country
- USA
- Snowmobile
- 2006 Attak
1015 Viper
Wow, those are in a hard to reach area! Sitting on sled, left to right; 3/4, 1/2, 5/8. I'm going to see if I can get hold of a sync tool and check actual pressure readings-
So I've been doing some tinkering with my sled and shared a few words with Cannondale. I originally took my sled apart because my dealer had my boost sensor plumbed into the Blue waste gate hoses that MPI uses. I removed that section and plumbed my boost gauge into the 5 bridged fitting that is attached to all 3 of the throttle's vacuum ports as well as goes to the BOV on the turbo. I threw the sled back together enough to run. At first my AEM's boost gauge was reading between 4-10 inHG vacuum. I shut the sled off, finished putting it back together and started it again. Now I can watch my AEM gauge sweep down counter clockwise past 30 inHG and shows this in the read out of the gauge.....( - - - ). Now I'm thinking my gauge is faulty or the sensor has gone for a crap. I run it up on the stand (I know no load) and can get it to read 0, sometimes boost if I'm hard enough on it, etc.
So now I send Cannondale a message, inquiring about how much vacuum these engines should be "pulling" at idle and told him about my vacuum readings. He mentioned it depends which ports are being used on the throttle bodies which could be the reasoning for my high vacuum readings. I start thinking and go back out to the shop and pull my sled apart again.
This is what I have found and tested with my sled. I unhooked the hose right at the blow off valve on the turbo. I left the 5 bridge fitting all hooked up and just blew into the hose off the BOV. I could ever so slightly hear air coming out of the intake tube for my air filter. While blowing through the BOV hose still, I started pushing on the throttle. As soon as I moved the throttle valves, the air noise got noticeably louder coming out of my air filter pipe. Which is leading me to believe that said ports that I'm hooked to are after the throttle valves of the throttle bodies. The OTHER ports on the carbs, I'm going to right now guess they are PRE throttle valve ports. I did not have time to test this tonight, but I will for sure tomorrow after work! Since my Vacuum/Boost gauge is hooked up post throttle valve's, it would make sense why my vacuum readings are so high at idle, throttle valves closed.
But now all of this leads me to another fun fact. If you look at MCX's BOV hook up lines and MPI's BOV hook up lines they are using the two different ports! In the MPI instructions is states to make sure to use the ports farthest from the manifold face (farthest from engine). While in the MCX picture, it's showing hooking up to the ports closest to the engine. Does anyone know from their own testing if all 6 of these ports are getting a reading from the same area of the carb? I'm still going to move my BOV hoses to the MCX ports to see if the air flows differently audibly through the carbs/intake and I will post up my findings! I can also take pictures of what I'm doing if need be!
Maybe Allen could help out in regards to which ports are which???
Here are the pictures of both MCX and MPI hook ups.
MCX
MPI
So now I send Cannondale a message, inquiring about how much vacuum these engines should be "pulling" at idle and told him about my vacuum readings. He mentioned it depends which ports are being used on the throttle bodies which could be the reasoning for my high vacuum readings. I start thinking and go back out to the shop and pull my sled apart again.
This is what I have found and tested with my sled. I unhooked the hose right at the blow off valve on the turbo. I left the 5 bridge fitting all hooked up and just blew into the hose off the BOV. I could ever so slightly hear air coming out of the intake tube for my air filter. While blowing through the BOV hose still, I started pushing on the throttle. As soon as I moved the throttle valves, the air noise got noticeably louder coming out of my air filter pipe. Which is leading me to believe that said ports that I'm hooked to are after the throttle valves of the throttle bodies. The OTHER ports on the carbs, I'm going to right now guess they are PRE throttle valve ports. I did not have time to test this tonight, but I will for sure tomorrow after work! Since my Vacuum/Boost gauge is hooked up post throttle valve's, it would make sense why my vacuum readings are so high at idle, throttle valves closed.
But now all of this leads me to another fun fact. If you look at MCX's BOV hook up lines and MPI's BOV hook up lines they are using the two different ports! In the MPI instructions is states to make sure to use the ports farthest from the manifold face (farthest from engine). While in the MCX picture, it's showing hooking up to the ports closest to the engine. Does anyone know from their own testing if all 6 of these ports are getting a reading from the same area of the carb? I'm still going to move my BOV hoses to the MCX ports to see if the air flows differently audibly through the carbs/intake and I will post up my findings! I can also take pictures of what I'm doing if need be!
Maybe Allen could help out in regards to which ports are which???
Here are the pictures of both MCX and MPI hook ups.
MCX
MPI
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Great work Dinner!
Thanks! It has me thinking now for BOV reasons and doing testing for synchronizing the carbs. IF the 6 ports are different lets say (3 PRE Vacuum and 3 POST vacuum). If people hook onto the PRE ports instead of the POST ports, the vacuum readings should be different but also which one is more accurate for when setting up the carbs??
Janne339, does your Nytro Manual show which ports to hook up the Synchro tool to?
Janne339, does your Nytro Manual show which ports to hook up the Synchro tool to?
The ports before throttle plate closest to engine would be the ones to sync with. Nytro has different port location so does not apply to us. Keep going guys we need to analyze everything to figure out how to make this motor best it can be! Awesome work!
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Ah right right, forgot they were different throttle body. I will see what I find tomorrow!
