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lightning intake plumbing questions

4x4man514

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hey guys i finally got my motor in and am wiring the whole truck up now. trying to get through the last few things but i still have a few questions about this lightning intake.

1. what part of the intake do i need to plumb the can p valve into and

2. there is a 3/8 vent on the oil filler neck. where do i tie this in? do i just cap it? the intake has a pvc valve in the rear of the intake that is tied into the underbody of the large part of the intake and a "bar " that runs across the bottom.

there is no tubes or places to attach a tube on the throttle body.

thanks!
 

904Bronco

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1) Vacuum to one side of Purge valve and the other to the CC. Usually, the Purge valve will have very small marking with an arrow that points to the engine side/vacuum. For Explorer or Mustang Upper Plenum I usually use one of the existing ports for a vacuum source. Not certain on a Lightning intake... Others that have can chime in, maybe.

2) You have to replace the air that is being draw into the PCV. The EFI system is set up to know/compensate for this.
Capping the inlet at the oil fill is not a good idea. Is there a boss on the TB that you can drill out and add a fitting to? Pictures would help for this.

Worse case - add a tube port in the piping to the air filter.
 

Green_Bastard

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On the bottom of the intake, one port will go the fuel pressure regulator, one to the PCV valve, and if needed, one to the brake booster. Block any unused. The port on the fill neck should go to a port on the air intake tube between the MAF and the TB.

I don’t need vacuum for the brake booster since I’m running HB so I connected the 2 large ports with a T fitting and on to the PCV.
 
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4x4man514

4x4man514

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1) Vacuum to one side of Purge valve and the other to the CC. Usually, the Purge valve will have very small marking with an arrow that points to the engine side/vacuum. For Explorer or Mustang Upper Plenum I usually use one of the existing ports for a vacuum source. Not certain on a Lightning intake... Others that have can chime in, maybe.

2) You have to replace the air that is being draw into the PCV. The EFI system is set up to know/compensate for this.
Capping the inlet at the oil fill is not a good idea. Is there a boss on the TB that you can drill out and add a fitting to? Pictures would help for this.

Worse case - add a tube port in the piping to the air filter.
ill have to look later today to see if there is a spot one could be drilled into. i hadnt thought of that option. ill get a pic too.

so the can doesnt really matter what part on the intake it gets pulled into. got ya
 
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4x4man514

4x4man514

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On the bottom of the intake, one port will go the fuel pressure regulator, one to the PCV valve, and if needed, one to the brake booster. Block any unused. The port on the fill neck should go to a port on the air intake tube between the MAF and the TB.

I don’t need vacuum for the brake booster since I’m running HB so I connected the 2 large ports with a T fitting and on to the PCV.
got ya. im running hydra boost as well so there is an extra port on the bottom but one is dead in the way of the throttle cable so ill prolly want to put a tee on the other
 

jamesroney

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ill have to look later today to see if there is a spot one could be drilled into. i hadnt thought of that option. ill get a pic too.

so the can doesnt really matter what part on the intake it gets pulled into. got ya
Do you want the theory of what is correct, or the practical of what you can get by with?

The Lightning intake, as well as all GT40 and 5.0 HO, and all SEFI windsor based engines use an upper plenum with scavenge ports for the PCV system. The theory is that any oil or fuel that ends up deposited in the upper plenum will be scavenged by the moving air and delivered to the cylinder. So the PCV is connected to the lowest location in the upper plenum. and usually has a TEE to the other locations that might accumulate liquid. When the PCV is flowing, the liquids are sucked into the engine and burned. You can certainly connect the PCV to the brake booster port...but then there's no way to "drain" the upper plenum if it gets full of oil. The Brake Booster will flow very little air. They use so little air, that the Mass Air Meter ignores it. But the PCV leaks a lot of air into the engine, and that air needs to be measured by the Mass Air Meter. So the clean air port needs to be downstream of the MAF, and upstream of the throttle butterfly. That port exists on the Mustang Throttle Body, and on the cold air pipe on the Explorer.

With all that said....no, it really doesn't matter where you port your PCV. Until it does. (...and it never does.) But you don't want to port it too close to the Booster port. You want those as far as possible from each other. (because the PCV leak will reduce the vacuum available to the booster. Also, you want the PCV vacuum "leak" to be equally distributed to all cylinders. So they run a TEE to both ends of the plenum.

Enjoy.
 
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4x4man514

4x4man514

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So I think I'm starting to understand a little better. But I cant see anywhere on this tb to tie into. In fact I've been looking online and it seems mine is the only one I've seen without a port on it. How lucky am I? Lol
 

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DirtDonk

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It’s an aftermarket Holley throttle body. Probably just didn’t come with one like the factory piece did.
Might’ve even have been intended originally for another application where the port was in the intake tube rather than the throttlebody itself.
 
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4x4man514

4x4man514

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It’s an aftermarket Holley throttle body. Probably just didn’t come with one like the factory piece did.
Might’ve even have been intended originally for another application where the port was in the intake tube rather than the throttlebody itself.
so do yall think its a good throttle body? or should i look into something else?
 

904Bronco

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I would say, stick with what you have until it proves otherwise.

I ran a BBK/Edelbrock 70mm TB. Very twitchy unit, stiffer spring. I couldn't get rolling as I would Launch even while feathering the pedal.

Ended up modifying the Explorer 65mm TB and it was much better.
 
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4x4man514

4x4man514

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ok cool. sounds good. is there a good source for finding the tubes, maybe one with a port in the side of it for that line we were discussing earlier? i must not be using the right terminology cause nothing i type in seems to come up.
 

Broncobowsher

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I would say, stick with what you have until it proves otherwise.

I ran a BBK/Edelbrock 70mm TB. Very twitchy unit, stiffer spring. I couldn't get rolling as I would Launch even while feathering the pedal.

Ended up modifying the Explorer 65mm TB and it was much better.
I had the exact same experience years ago. Didn't notice any loss in power going back to the 65mm. But did gain huge amounts of drivability. With the 70mm you had idle, and making power. There was no just off idle level. Trying to cruise the highway, it was either on the throttle accelerating, or coasting. That area just off idle where you could cruise at didn't exist.

I may have missed it, but the PCV is a system, not a part. There is a PCV valve that is part of the system.
Now that nipple on the fill tube. That lets fresh air in while the PCV is pulling fumes out of the engine. Since it is part of the air being consumed by the engine it should be plumbed into the intake duct between the MAF and the throttle body. This is clean filtered air. It is also metered air. It is air entering the engine to be mixed with fuel and burned. It does take a detour getting there, going through the engine and through the PCV valve. But it is still air, it is not being combusted inside the crankcase. The blowby that is being mixed with that air is either already burned and inert, or already mixed with fuel and ready for a second chance to be burned.
That vent nipple also has a second use. Under heavy loads where there isn't vacuum pulling air through the crankcase. There is still blowby getting into the crankcase. It has to go somewhere. The PCV isn't going to do it, the spring loaded valve is closed. But that vent that normally lets air in, it can now let blowby out. let it loft into the intake and be burned.
 

lars

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So I think I'm starting to understand a little better. But I cant see anywhere on this tb to tie into. In fact I've been looking online and it seems mine is the only one I've seen without a port on it. How lucky am I? Lol
Everyone else has done a great job of explaining the how's and why's of the PCV system. Here's maybe something that can help get the plumbing done.

In the third photo you posted, it looks like there's a rusty bolt head to the left of the throttle position sensor. That's right about where the breather nipple would normally be on an OEM and some aftermarket throttle body. Makes me wonder if you can remove the bolt and screw in a barb fitting or similar.

For reference, I'm attaching some ancient (as in, nothing in the photos is in my Bronco anymore) that show the stock Ford connection from the oil fill tube on the valve cover to the throttle body. Even if what I think is a rusty bolt head on the third photo isn't, you can probably drill/tap into that location, say 1/8" NPT, and put in a street elbow and hose barb to accomplish the same thing.
 

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4x4man514

4x4man514

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Everyone else has done a great job of explaining the how's and why's of the PCV system. Here's maybe something that can help get the plumbing done.

In the third photo you posted, it looks like there's a rusty bolt head to the left of the throttle position sensor. That's right about where the breather nipple would normally be on an OEM and some aftermarket throttle body. Makes me wonder if you can remove the bolt and screw in a barb fitting or similar.

For reference, I'm attaching some ancient (as in, nothing in the photos is in my Bronco anymore) that show the stock Ford connection from the oil fill tube on the valve cover to the throttle body. Even if what I think is a rusty bolt head on the third photo isn't, you can probably drill/tap into that location, say 1/8" NPT, and put in a street elbow and hose barb to accomplish the same thing.
thanks guys!

lars i dont know how but somehow i overlooked the "rusty bolt " in the pic. im gonna have to go check that out in the morning and see if that is a valid option. i sure hope it is
 
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4x4man514

4x4man514

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Everyone else has done a great job of explaining the how's and why's of the PCV system. Here's maybe something that can help get the plumbing done.

In the third photo you posted, it looks like there's a rusty bolt head to the left of the throttle position sensor. That's right about where the breather nipple would normally be on an OEM and some aftermarket throttle body. Makes me wonder if you can remove the bolt and screw in a barb fitting or similar.

For reference, I'm attaching some ancient (as in, nothing in the photos is in my Bronco anymore) that show the stock Ford connection from the oil fill tube on the valve cover to the throttle body. Even if what I think is a rusty bolt head on the third photo isn't, you can probably drill/tap into that location, say 1/8" NPT, and put in a street elbow and hose barb to accomplish the same thing.
Ding ding ding we have a winner!

You were exactly right that is a threaded hole into the bore. I cant believe i mised that.

My next issue is it looks like the tps is sitting in the way of putting a nipple. Can that be moved or clocked any? It looks like the corner of the plug is causing interference just a little.
 
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