Engine Explorer intake vacuum line diagram

Mustang5L5

i'm familiar with penetration
Mod Dude
Feb 18, 2001
34,958
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Massachusetts
Have seen this question asked a million times. So here's a diagram.

This is an EARLY Explorer intake with the EGR port. There were two lower manifolds. The RF-F87E-9K461-BA lower was early and had the bosses present for the ACT. The RF-F87E-9K461-BB lower was later (non-EGR) and lacks the boss. You can still carefully drill/tap the runner.

Upper manifold changed a few times. Some had COOLANT lines plumbed to one of the rear ports. For the most part, the below diagram is what you are trying to create to allow you to easily bolt on the explorer intake like the factory manifold. You can easily grab the vac lines and twist/pull to remove them. If you don't want to drill/tap for new hose barbs, you can carefully cut the tubes and hose clamp a line onto the stub. You do lose the securing ridge however.

Obviously if you are not running the EGR, or using a 93 Cobra upper intake with the Explorer lower, you do not need the coolant boss in the lower intake. There are technically two bosses at the rear of the lower. If for whatever reason you need to flip the intake to the driver's side TB orientation, drill/tap the other one. I drill/tapped both for 3/8" and plugged the unused port as it makes a good spot for a future temp sensor (although the coolant runs a little colder at the rear of the intake so keep this in mind)

Same goes for charcoal canister, or you are speed density. In that case, you can just drill/tap and plug those ports if not needed. I also route the PCV line closer to the factory 87-93 configuration in this diagram.

Use NPT sizes for the upper intake as reference only because the vac tube sizes changed over the years. The NPT size refers to what is drilled and tapped into the intake. I'm using 1/4" barb fittings for the vac lines. You can use whatever matched the vac hose you are using. You will need to source the NPT to barb fittings from various outfitters like your local hardware store, McMaster-Carr or maybe even Amazon

Explorer Intake vac line diagram.jpg


also, if you do have an early explorer intake like above and have the throttle body as well, it can be converted for use on the mustang. See below thread

 
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Foxslider

im not that much of a idiot
Oct 25, 2019
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Cool. Need to put mine on already. Gotta finish porting it and hydro dip them. (Woodgrain)

You can swap lower intakes w/o having to disconnect fuel line right?
 

LATT5133

Member
May 8, 2020
46
18
18
50
Tampa, Florida
Have seen this question asked a million times. So here's a diagram.

This is an EARLY Explorer intake with the EGR port. There were two lower manifolds. The RF-F87E-9K461-BA lower was early and had the bosses present for the ACT. The RF-F87E-9K461-BB lower was later (non-EGR) and lacks the boss. You can still carefully drill/tap the runner.

Upper manifold changed a few times. Some had COOLANT lines plumbed to one of the rear ports. For the most part, the below diagram is what you are trying to create to allow you to easily bolt on the explorer intake like the factory manifold. You can easily grab the vac lines and twist/pull to remove them. If you don't want to drill/tap for new hose barbs, you can carefully cut the tubes and hose clamp a line onto the stub. You do lose the securing ridge however.

Obviously if you are not running the EGR, or using a 93 Cobra upper intake with the Explorer lower, you do not need the coolant boss in the lower intake. There are technically two bosses at the rear of the lower. If for whatever reason you need to flip the intake to the driver's side TB orientation, drill/tap the other one. I drill/tapped both for 3/8" and plugged the unused port as it makes a good spot for a future temp sensor (although the coolant runs a little colder at the rear of the intake so keep this in mind)

Same goes for charcoal canister, or you are speed density. In that case, you can just drill/tap and plug those ports if not needed. I also route the PCV line closer to the factory 87-93 configuration in this diagram.

Use NPT sizes for the upper intake as reference only because the vac tube sizes changed over the years. The NPT size refers to what is drilled and tapped into the intake. I'm using 1/4" barb fittings for the vac lines. You can use whatever matched the vac hose you are using. You will need to source the NPT to barb fittings from various outfitters like your local hardware store, McMaster-Carr or maybe even Amazon

Explorer Intake vac line diagram.jpg


also, if you do have an early explorer intake like above and have the throttle body as well, it can be converted for use on the mustang. See below thread

Question on this, so I have a non EGR version, bought the car that way. I want to get an internal EGR version just like what you have here. Was it difficult to have the EGR coolant provision drilled? Is the risk of cracking while drilling the hole really an issue or is it overblown? I want the internal EGR version so my entire pollution control system works properly as i do daily drive my FOX. Right now my coolant return line is just plugged? I would like your thoughts on this option versus just getting a new aftermarket manifold with all the proper provisions? Thanks for your time and for all of the awesome tips and info you put on here! All the Best Jason
 

Mustang5L5

i'm familiar with penetration
Mod Dude
Feb 18, 2001
34,958
11,061
224
Massachusetts
The rear coolant ports are easy to drill and tap. The key is going nice and slow with the right size drill bit that is nice and sharp.

once drilled, same technique with the tap and some cutting fluid. Go slow, back it out and clean out often and relube.

usually the cracking is caused by using the wrong size drill bit prior to tapping and going way to fast with the tap and not clearing the chips.
 

LATT5133

Member
May 8, 2020
46
18
18
50
Tampa, Florida
The rear coolant ports are easy to drill and tap. The key is going nice and slow with the right size drill bit that is nice and sharp.

once drilled, same technique with the tap and some cutting fluid. Go slow, back it out and clean out often and relube.

usually the cracking is caused by using the wrong size drill bit prior to tapping and going way to fast with the tap and not clearing the chips.
thanks for the input!!
 

LATT5133

Member
May 8, 2020
46
18
18
50
Tampa, Florida
Have seen this question asked a million times. So here's a diagram.

This is an EARLY Explorer intake with the EGR port. There were two lower manifolds. The RF-F87E-9K461-BA lower was early and had the bosses present for the ACT. The RF-F87E-9K461-BB lower was later (non-EGR) and lacks the boss. You can still carefully drill/tap the runner.

Upper manifold changed a few times. Some had COOLANT lines plumbed to one of the rear ports. For the most part, the below diagram is what you are trying to create to allow you to easily bolt on the explorer intake like the factory manifold. You can easily grab the vac lines and twist/pull to remove them. If you don't want to drill/tap for new hose barbs, you can carefully cut the tubes and hose clamp a line onto the stub. You do lose the securing ridge however.

Obviously if you are not running the EGR, or using a 93 Cobra upper intake with the Explorer lower, you do not need the coolant boss in the lower intake. There are technically two bosses at the rear of the lower. If for whatever reason you need to flip the intake to the driver's side TB orientation, drill/tap the other one. I drill/tapped both for 3/8" and plugged the unused port as it makes a good spot for a future temp sensor (although the coolant runs a little colder at the rear of the intake so keep this in mind)

Same goes for charcoal canister, or you are speed density. In that case, you can just drill/tap and plug those ports if not needed. I also route the PCV line closer to the factory 87-93 configuration in this diagram.

Use NPT sizes for the upper intake as reference only because the vac tube sizes changed over the years. The NPT size refers to what is drilled and tapped into the intake. I'm using 1/4" barb fittings for the vac lines. You can use whatever matched the vac hose you are using. You will need to source the NPT to barb fittings from various outfitters like your local hardware store, McMaster-Carr or maybe even Amazon

Explorer Intake vac line diagram.jpg


also, if you do have an early explorer intake like above and have the throttle body as well, it can be converted for use on the mustang. See below thread

Mike, I just lucked out and picked up an Explorer intake with EGR so I can restore the last bit of non working equipment in my Fox. My question is this, looking at the photo the PCV has two inputs on the Explorer intake vice the factory Fox intake. In your photo the Explorer intake feeds the PCV from the underside front and center port which runs to a T on the outer plenum then to the PCV. Is this necessary or can you omit one? I am asking to determine why it is run like this and if it is a necessity? Taking the whole set up to the bead blaster tomorrow and then purchasing my fittings to mimic your build. Thanks as always! Jason
 

Mustang5L5

i'm familiar with penetration
Mod Dude
Feb 18, 2001
34,958
11,061
224
Massachusetts
I’m going off memory off an old post, but I believe the reasoning is oil pooling in the plenum. By having the two ports, oil has path back through the pcv but you still have an open vac port.

but I could be wrong. I haven’t looked into it extensively but all the factory oem Ford plenums use two lines for the pcv in a tee. One to bottom of plenum and one to the neck.
 

LATT5133

Member
May 8, 2020
46
18
18
50
Tampa, Florida
I’m going off memory off an old post, but I believe the reasoning is oil pooling in the plenum. By having the two ports, oil has path back through the pcv but you still have an open vac port.

but I could be wrong. I haven’t looked into it extensively but all the factory oem Ford plenums use two lines for the pcv in a tee. One to bottom of plenum and one to the neck.
That makes perfect sense, so it stays! Thanks again for your time!
 

jrichker

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lowendmac.com
@Mustang5L5

The single hose barb is an excellent place for the fuel pump pressure regulator. That way moving the A/C controls doesn't change the vacuum seen by the fuel pump pressure regulator. It also prevents fuel from getting in the vacuum system and power brake booster if the fuel pump pressure regulator diaphragm springs a leak,
 
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