Build Thread Want To Blow 5 Years And $50k On A Foxbody? Step By Step Instructions Inside!

[RacEoHolic330]

Now that I have a plan to tackle the fuel heating issue, it's time to come up with a plan for the other thing that's bothering me.

My catch can breather puffs smoke (vapor?) at hot idle. It's not a ton, but because the breather is sitting right at the corner of the hood, it's visible when the car isn't moving. That annoys me.

It's my understanding that some vapor from the catch can is nothing to worry about. I have a 1/4" of fluid on the bottom on the can. That is with about 200 miles and a few dyno pulls. I would be more concerned if the can was full, but I couldn't believe how little is in there.

I think the visible vapor is a combination of having 3 breather lines (one from each valve cover and one from the lower intake) as well as those lines being very short. Most guys have longer lines so that vapor gets a chance to settle along the lines and turn to liquid before it hits the breather.

My plan is basically to take the line from the lower intake and run it into the exhaust using a scavenging kit. The lines from the valve covers will still go to the vented catch can, but the third line will dump into the exhaust instead of going to the can like it does now. The scavenging line is supposed to pull about 3in of vacuum. Will my exhaust have enough airflow at idle to pull a vacuum through that line? I guess I'll have to try it to find out. From what I have researched, the crankcase would benefit from a little extra vacuum. A check valve will be used on the scavenging line to prevent exhaust backpressure at high rpm from pressurizing the crankcase.

This is all assuming that the lower intake line is the one pumping out the most vapor. I need to disconnect it from the breather first to find out.

Or am overcomplicating all this? Should I just disconnect the line from the lower intake and cap both ends and let the lines from each valve cover do their thing? Maybe my idea of three vent lines is just causing more trouble than its worth. The curious part of me still wants to see if scavenging the crankcase via the exhaust if effective on my setup.

 

[hoopty5.0]

I read something that @Sharad posted the other day on FB about their catch can system. The success seemed to be in the length of the lines. Maybe he'll see this and can expand on that.

 

[84Ttop]

3 vents is overkill in my book, my fix for the smoke out the breather is to use a gym elastic wrist band over the filter element in the top of my catch can. I change it every few months when it gets soaked in oil and have never looked back. I buy them a case at a time in green from some Chinese distributor on ebay

I can understand how the smoke coming from under the hood is less than ideal, it always makes me think i've got parts falling off the car when I see smoke lol

 

[RacEoHolic330]

I have the breather filter stuffed with steel wool and a wristband. The vapors still sneak out. I'll disconnect the lower intake vent first and see if that's my vapor source.

 

[89oem]

I thought steel wool was a no no, as small pieces could get sucked back into the motor via the vacuum tube,

 

[RacEoHolic330]

The breather does provide fresh air for the crankcase, but I'm not sure it sucks air in so hard that it could pull the wool apart. You make a good point though. I'll probably take it out anyway because it didn't seem to help much.

 

[RacEoHolic330]

Yesterday was relatively productive.

I removed and reinstalled the water neck to fix a coolant leak. I also removed and reinstalled the
front portion of the water pump to fix another coolant leak. If I get another coolant leak, I'm going to lose it!

I also removed the stainless breather and coolant lines and replaced all them with black nylon lines. Not only does it look nicer to me, but I think it will help with underhood temps. That stainless braid held a ton of heat. I'm not replacing the fuel lines, but I am going to put heat sleeves over them.

I got the return line rerouted through the rear frame rail. I drilled a hole in front of the lower control arm mount to give me an access point to the frame rail. I used electrical heat shrink to protect the portion of the braid that is in the frame rail. It all worked out pretty well. I didn't need to shorten or extend the line at all.

Now I just need to repeat on the driver side and then insulate the tank.

 

[RacEoHolic330]

Got a few rolling shots back over the weekend. Came out awesome!

 

[Noobz347]

I don't own that camera. My coworker's wife does laser therapy on horses. She uses it to visually see the inflammation (and heat) decrease as she performs the treatments. It's a $1,500 camera. I'm going to get myself a cheap point and shoot temp gun eventually. It will be helpful to have. For now, I have a fancy camera available to me if I ever need to see something.

Yeah... That thing would be badass to play with for a week or so. I'm sure that right about now @madmike1157 's gears are turning. There's probably a little dribble starting to appear at the corners of his mouth.

Oops. Just coffee. I didn't get it on my shirt though.

 

[Noobz347]

Now that I have a plan to tackle the fuel heating issue, it's time to come up with a plan for the other thing that's bothering me.

My catch can breather puffs smoke (vapor?) at hot idle. It's not a ton, but because the breather is sitting right at the corner of the hood, it's visible when the car isn't moving. That annoys me.

It's my understanding that some vapor from the catch can is nothing to worry about. I have a 1/4" of fluid on the bottom on the can. That is with about 200 miles and a few dyno pulls. I would be more concerned if the can was full, but I couldn't believe how little is in there.

I think the visible vapor is a combination of having 3 breather lines (one from each valve cover and one from the lower intake) as well as those lines being very short. Most guys have longer lines so that vapor gets a chance to settle along the lines and turn to liquid before it hits the breather.

My plan is basically to take the line from the lower intake and run it into the exhaust using a scavenging kit. The lines from the valve covers will still go to the vented catch can, but the third line will dump into the exhaust instead of going to the can like it does now. The scavenging line is supposed to pull about 3in of vacuum. Will my exhaust have enough airflow at idle to pull a vacuum through that line? I guess I'll have to try it to find out. From what I have researched, the crankcase would benefit from a little extra vacuum. A check valve will be used on the scavenging line to prevent exhaust backpressure at high rpm from pressurizing the crankcase.

This is all assuming that the lower intake line is the one pumping out the most vapor. I need to disconnect it from the breather first to find out.

Or am overcomplicating all this? Should I just disconnect the line from the lower intake and cap both ends and let the lines from each valve cover do their thing? Maybe my idea of three vent lines is just causing more trouble than its worth. The curious part of me still wants to see if scavenging the crankcase via the exhaust if effective on my setup.

Can I ask a silly question? Why are you not running a closed system?

 

[RacEoHolic330]

Can I ask a silly question? Why are you not running a closed system?

A closed system creates a sealed crankcase under boost because of the need for a check valve. That's fine for lower boost numbers, but can cause crankcase pressure issues when the boost levels start to climb. The unanimous consensus seems to be to run breathers if there are no emissions regulations preventing you from doing so. The trade off with that is it causes the oil to become dirty with blow by a lot faster because there is no PCV setup pulling the hydrocarbons out of the oil and burning them in the intake.

I figured that having the lower intake connected to a scavenge line at the exhaust will get me that PCV effect by pulling the vapors into the exhaust and burning them there. With this mainly being a street car, it would be nice to keep the oil clean if I can. That's only if the scavenge line actually works at idle though.

 

[Noobz347]

Yeah... Seen those setups before too. There's really nothing wrong with running a closed system so long as it is designed to accommodate the application.

I think that the whole "A closed system will kill my motor" thing comes from all the time people spend at the track with these cars. They of course, could give a rat's rear end about any of it.

The only reason I mention this is because you had to have previously known that it was going to out gas and that the vapor would have oil in it. As OCD as you are about this project, I'm really surprised that went this route. Even a crank case vac pump would have been an option.

 

[RacEoHolic330]

I knew there would be vapors, but I assumed most of them would turn to liquid before getting to the catch can. I think my super short breather lines have a lot to do with that. I think the source of the vapor is coming from the line off the lower intake, which is the one that I'd like to direct to the exhaust. I could just cap it and call it a day, but that's going to make the oil get that much dirtier.

I've heard such mixed info about vacuum pumps, so I stayed away from that route. So many horror stories about them failing within a few thousand or even hundred miles. Not to mention the turbo piping making it very difficult to have room to add more accessories.

Because I have a speed density setup, there should be no hurt in running the lower intake back into the upper intake (with a check valve) while keeping the breathers functioning. That way, the breathers can do their thing during boost and the line off the lower can do its thing during idle and part throttle to keep the oil clean. That might be an option?

 

[Noobz347]

Possibly... The other thing that comes to mind concerning vac tubes is velocity. The smaller the tube the quicker that air volume will want to move as the force increases.

You can slow things down by increasing orifice and line size and/or increase the number of lines that are pulling vac. The slower all of that air moves, the less oil vapor will be picked up and allowed to escape through your breathers.

I might look into a way to slow that air down to keep the oil vapor inside of the catch can.

 

[RacEoHolic330]

Once I'm done with my fuel line insulation business, I'm going to fire the car up with the lower intake capped to see how the vapor situation is at idle with just the two 12an lines from the valve covers. I removed all the breather lines over the weekend to replace with nylon hoses. The valve cover lines didn't smell like much, but the lower intake line had a strong oil/fuel smell. I think that's the line to blame, but I'd like to know for sure.

 

[84Ttop]

@Sharad this man needs on of your newly fangled super terrific catch cans!
Seriously @RacEoHolic330 you should look into their catch cans, best design I've ever seen hands down.

 

[90lxcoupe]

I read a discussion on yellowbullet with some of the best engine builders in the world talking about best places to pull crankcase vacuum, they all pretty much said they like the idea of using the valley plate on a lower intake, but it takes a TON of work to not get oil in the hose. Ditch that hose and i bet you will be good.

 

[RacEoHolic330]

You're probably right that ditching the lower intake hose will eliminate the huffing at idle. Nick voiced the same opinion.

Here's my question though. What effect will that have on my oil life and oil quality? Breathers on a race car that gets oil changes every week is fine, but what negative effects will that have on a street car. Those hydrocarbons aren't being pulled out of the oil so they hang around in the crankcase and eventually turn to blow by in the oil. The car will see 2k miles a year at best. Should I be changing my oil every 500 miles? 1000 miles? I just want to be sure I'm not prematurely wearing my engine internals if I can avoid it.

 

[RacEoHolic330]

@Sharad this man needs on of your newly fangled super terrific catch cans!
Seriously @RacEoHolic330 you should look into their catch cans, best design I've ever seen hands down.

Do you have a link to said super terrific catch can?

 

[CarMichael Angelo]

Do you have a link to said super terrific catch can?

I'm sure the huffing vapor you're talking about is the same vapor I seem to have. Although I still have a break in to get past, I'm wondering how bad of an idea it is to run a very small "t'd" hose back into the intake tube before it gets metered to suck back some of the vapor for the sake of burning it?

I know that too much will be a bad thing and could compromise the intake mixture, and lead to possible detonation, but consider this: Once it gets on boost anyway, that tube is no longer allowing anything to come into the intake stream that used to be vacuum based, especially if you put a one way valve in the t'd line. it's the other path to trying to suck it out into the exhaust flow when there may not be enough velocity at idle to create a vacuum to do it, and one I'm considering doing.