Author Topic: Pan evac question  (Read 1446 times)

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KMcCullah

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Pan evac question
« on: May 19, 2019, 03:59:52 PM »
Dad and I finished hooking up the pan evac system for our F100 yesterday. We also plumbed a nice quality vacuum gauge to the crank case to see if we're getting any vacuum. We made a couple WFO passes and saw maybe 1 in/hg vacuum. Maybe. We are suspecting the flash arrestors could be restricting flow. The pan evac kit is the $29.95 one from Jegs.

What kind of crank case vacuum have you guys seen with pan evacs?

Kevin McCullah


cjshaker

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Re: Pan evac question
« Reply #1 on: May 19, 2019, 09:40:57 PM »
When I asked about header evac systems before, I think the response was that 1-1 1/2" was about the norm for that type of system. I decided it wasn't worth the effort in the cramped engine compartment of a Mustang, but there's plenty of room in your truck.
Doug Smith


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Falcon67

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Re: Pan evac question
« Reply #2 on: May 20, 2019, 11:23:35 AM »
Depends on how you install the tubes in the header collectors.  If the tubes are installed per the instruction sheet (same one used for the Moroso evac kit) IMHO they told you wrong.  The end of the tube should not face down, parallel to the sides of the collector.  They should be turned to face outward towards the open end of the collector. 

« Last Edit: May 20, 2019, 04:51:37 PM by Falcon67 »

winr1

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Re: Pan evac question
« Reply #3 on: May 22, 2019, 09:17:00 PM »
On a setup installed optimally, what kind of pressure drop might one see ??

Curious as to idle, crusin an all barrels wide open




Ricky.

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Re: Pan evac question
« Reply #4 on: May 23, 2019, 08:18:21 AM »
I haven't measured - my test is to pull the hose off the cover cap and put my thumb over the hose.  If I can feel suction, we're good.  Also blow through the hose to check the valve, suck back -if you get air, replace the valve.  They last various amounts of time.  Last set I got from NAPA have lasted a good while.  The ones that come with the kits may last a season, may not.  Since you started with a kit, I'd go get two good ones for spares and have them ready.