FrontEngineDragsters.Org Forum

Technical => Spud Miller's Cave => Topic started by: spitzerscott on August 29, 2015, 12:47:13 PM

Title: BV leakdown
Post by: spitzerscott on August 29, 2015, 12:47:13 PM

Need to check my bv leakdown.  Single butterfly unit on 4-barrel manifold, I have unit off engine and would like to set this on the bench.  My question is, all I have are runner nozzles, so I have 8 lines coming from my distribution block.  To simulate for my .028 nozzle jets, should I cap some of these lines?  Or would I be better off to put it back on the engine and check it?

Title: Re: BV leakdown
Post by: Spud Miller on August 29, 2015, 12:57:16 PM

 When you set the barrel valve leakdown, you're setting the size of the "leak" in the barrel valve.

 The nozzles have no play in that whatsoever...you're not measuring the flow through the nozzles...JUST the spool in the valve.

 In fact, if the nozzles are too small and create too much restriction (on a gas setup), sometimes it's necessary to remove a nozzle line to remove them from the situation.

 So, you could adjust the leakdown just fine off the car, disconnected from the fuel system completely.

 Spud

Title: Re: BV leakdown
Post by: spitzerscott on August 29, 2015, 01:13:55 PM

Thanks Spud.  I always appreciate your help.