Sam (Bones) Posted September 20, 2009 Share Posted September 20, 2009 what do you think of my method now??? I still need to try the 10.5 Quote Link to comment Share on other sites More sharing options...
kc8oye Posted September 20, 2009 Author Share Posted September 20, 2009 i still think you are asking for trouble going with a PV as high as your idle vac. sam.. but give it a whirl.. I figured out my 6.5 wasnt' big enough becuse of how far I had to get into the throttle to get down to 6.5.. it was making the secondaries open.. so a little bit of basic tuning knowledge told me a little bigger would help.. and it definately did! Quote Link to comment Share on other sites More sharing options...
kc8oye Posted September 20, 2009 Author Share Posted September 20, 2009 for as little effort as it takes to change a PV.. can't hurt to try it!!! Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted September 20, 2009 Share Posted September 20, 2009 I figured out my 6.5 wasnt' big enough because of how far I had to get into the throttle to get down to 6.5.. it was making the secondaries open.. so a little bit of basic tuning knowledge told me a little bigger would help.. and it definately did! EXACTLY!!!!! if I go to just at the point of opening the secondaries, my vacuum doesn't drop below 9-8.5", the 8.5 helped, now to try the 10.5, I'm betting it's going to help my drivability a bunch Quote Link to comment Share on other sites More sharing options...
kc8oye Posted September 21, 2009 Author Share Posted September 21, 2009 i'm sure it will sam.. but i'm not sure if you will have idle problems or not because of it.. if a blown pv is different from an open PV at idle.. then you might be ok.. cuz usually when a pv is blown from a back fire, the carb will idle very very very rich.. (I know you have pv blowout protection.. but I'm talking about the symptoms here) btw... over all I stepped up to 92 octane so I could run more timing (it would ping on 89) added another 4° of initial timing.. that means I'm 16 initial plus 21 mechancal.. 37 is right in the ball park now.. . and with the 5 jet sizes.. i went to pull out in front of a big truck last night, and it just blew the back tire off it.. that carb has never done that before.. it was making all kinds of crazy power... I know I said it before.. but I think I'm getting really close to joining the 13's club now :> Quote Link to comment Share on other sites More sharing options...
Heckeng Posted September 21, 2009 Share Posted September 21, 2009 A blown PV is different from a light one because a light one will simply open up to allow a larger passage for fuel to get to the primaries, but if the primaries are not active, it doesn't matter. A blown one keeps the valve shut, but fuel can go from the fuel bowl to the vacuum port on the main body of the carb, affecting fuel metering at all times. Basically if there is any vacuum under the carb, it will be sucking fuel through the PV torn diaphragm. Quote Link to comment Share on other sites More sharing options...
kc8oye Posted September 21, 2009 Author Share Posted September 21, 2009 ahhh ok.. that makes sense.. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.