Gen 3 950 dominator

[fishman]

I’ll find a different gauge as that what the gauge reads

[fishman]

I picked up another gauge and it is reading 6 inches of vacuum

[jmarkaudio]

I did this to show that a PV that is either open or closed at idle has no effect on idle fuel mixture. The carb is one of a pair of external boost referenced PV carbs, internal vacuum supply is plugged. Engine RPM was later brought up to the point boosters were active and confirmed the PV operation, you could then see the change in AFR readings. NEVER base PV selection on idle vacuum, if you check vacuum at a cruise RPM where the boosters are activated then you can find a usable point to select the proper PV.

[levisnteeshirt]

Close it and drill the throttle plates ,, that's a nice idea but it acts like a vacuum leak above idle ,, I wouldn't move the IFR unless you want to win a dyno contest

Drill about a 3/32 hole in each throttle plate on the outside half , see what it does ,, you could do only 2 and try that

Drilling the plates works better because above idle the modification leaves the equation ,, an open hole never leaves and is a vacuum leak constantly ,, its flawed thinking

[fishman]

Thanks Mark

I took the carb totally apart and blew every port out after I tried all the suggestions.... from power valves to trying to use the idle bypass to set rpm also opened up primary idle more and closed off more of secondary.. nothing worked in some cases car ran worse ... anyways after taking carb apart and blowing out all ports the four corner idle is balanced now.. mark I was thinking I’ll have to send the metering blocks to fix it.. how much would you charge
Thanks Garry

[jmarkaudio]

The t-slot restrictions as delivered on the one I reworked were at .063. A little larger than I would like but probably OK to start with. They don't need much, lower the idle feed, recalibrate emulsion, and a main and idle air bleed change. From there jet as needed. I'll message my number, give me a call.

[fishman]

Mark

I give you a call next week. I’m off to the mainland to race ... I live on Vancouver island