Turbo on 2000 Limited 5.0

[4pointslow]

Moving Maf

What would be the downsides of moving the maf pre turbo?
Expense of course, IAT would still need to be after turbo. I am sure there are more.
You would need some really long wires but that is not so bad.
What was your main reason for not going pre turbo?

 

[Dono]

The main reason was the blow off valve.
If the blow off valve is after the maf, when it releases pressure you screw up the a/f mixture and the motor stalls. Apparently this can be tuned around, but not easily.

With just venting to atmosphere (My first attempt), I didn't count on the smell and the moisture freezing the lines solid in the winter.

So, attempt #2 will be the hobbs switch system. I 'think' this will be the proper way of doing pcv, except under boost. Under normal driving it will be a closed system with no un-metered air getting in to the system, and no metered air escaping to atmosphere.
Under boost, the blow by (metered air) will escape to atmosphere making the a/f ratio slightly 'more' rich. With the new motor, I'm hoping blow-by will be very minimal making this a non issue.

 

[4pointslow]

Blow off

Sounds like it will work fine. The richness during boost (if it happens) can be easily tuned out too.


Could you turn the blow off valve into a recirculation valve, so that it dumps boost pressure from after the turbo to the inlet side of the turbo after the maf?
Where is your blow off valve?

 

[Dono]

Blow off valve is under the truck, passenger side front door along the frame rail just before the slot maf.

I did think about recirculating the bov. I'm just not sure what kind of volume I'd need in the tubing to release the pressure and recirculate. Probably not much.

One of the other reasons I liked the slot maf closer to the front of the truck (Just at the frame before heading up in to the wheel well- needed to be there so I had a nice long, straight run for good clean readings) is that if there are any boost leaks in the plumbing before the maf, the air metering will still read correctly and I won't get stranded.

With my pcv system, even if I were to move the maf pre-turbo, I'd still have to run a vacuum line all the way to the back of the truck and plumb it in-between the relocated maf (Pre-turbo) and turbo inlet. Running a line all the way to the back for vacuum is far from ideal. pressure losses, moisture (back to the possibility of the inside of the line freezing solid on me in the winter), etc.

Re-engineering our vehicles requires a lot of thought, and sometimes compromises it would seem. We do it because we love it though.

 

[Dono]

hobbs switch and pcv valve are here

The HPS-2 hobbs switch is awesome. I was able to adjust it so that just slight pressure from my mouth will make to key on. I have no clue, but this has to be well under 1 psi. This exceeded my expectations, and is a beautiful thing.

Also, the pcv valve seals completely with reverse pressure. Again, as long as it fits snug in the lower intake, I'm good to go.
edit:
STANDARD MOTOR PRODUCTS Part # V242 {#25095468, CV893C}----correct number. Cheap from rockauto - fits perfectly (tight) with a wrap of electrical tape. This is the one to use.
Alternate: Motorcraft PCV Valve that seals perfectly also: EV127A This one is more money, but it is Motorcraft.

I have a couple of different high flow one way valves for the filter. One style is adjustable open, and the other is very close to zero pressure to open.
All I need is the vent solenoid. I hope that exceeds expectations also.

I just need to figure out how I am going to make my holes in the intake plumbing for the intake tube and hobb's switch. I could drill a couple of small holes and use nuts on the inside of the aluminum pipe or silicone bend, but what if those nuts work loose and go thru the motor? Thoughts guys?

 

[jd4242]

Weld bungs onto the pipe..a regular flat nut and washers isnt going to seal..

 

[Dono]

I just wasn't sure if you could weld to that thin aluminum, and I need 1/4" bung.
If I were to go with a nut on the inside, I'd definitely use 'goop' to make sure there is a seal. I'm just not comfortable with that Nut on the inside.
I wonder if I could take a 1/4" nut and modify one side slightly to match the curve of the intake tube. Then, welding two dis-similar metals could be an issue. Not being a welder, I have no clue. Then there is the issue of paying a guy to do it for me. Edit......Tim might be able to help me on the welding

 

[jd4242]

They need to be same material. .it can be welded just needs to know how to weld..my dad did mine..never trust a nut or any flat object on round pipe

http://m.summitracing.com/search/pr...formance-weld-bungs/thread-size/1-4-18-in-npt

 

[Dono]

Thanks JD,
I didn't know they were that readily available. I see summit has all sizes.
This is definitely the correct way of doing this. I'll weld 2 on. One will be a 1/4" bung (SUM-220071) for a 3/8 nipple and the other will be for the hobbs switch. Excellent.

 

[jd4242]

Thanks JD,
I didn't know they were that readily available. I see summit has all sizes.
This is definitely the correct way of doing this. I'll weld 2 on. One will be a 1/4" bung (SUM-220071) for a 3/8 nipple and the other will be for the hobbs switch. Excellent.

Its hard to weld but definitely can be done..i got the thicker wall piping for all mine so was ""slightly easier..wrapped the pipe in wet towel and tack weldsss with a tig

 

[jd4242]

O word of advice when welding bungs in,find a bolt that fits the bung,put antiseize on it and screw it into the bung before welding..

 

[Dono]

Ok, If the thin walls make Tim cringe, I'll take it to a guy that welds for a living (He's done great work for me before).

I guess I might as well take a valve cover in to get a bung welded on for the oil return also. Tim gave me a factory set that has been powder coated. A shame to ruin the powder coating in that area, but....function over form.

 

[jd4242]

Ok, If the thin walls make Tim cringe, I'll take it to a guy that welds for a living (He's done great work for me before).

I guess I might as well take a valve cover in to get a bung welded on for the oil return also. Tim gave me a factory set that has been powder coated. A shame to ruin the powder coating in that area, but....function over form.

If you take and draw a cicle with a razor knife slightly bigger than the hole and peel/sand/scrap the coat off leaving enough room for hole and weld build up..then again wrap the rest of area with a wet towel and low heat welds,shouldnt mess the coat up..then just use some touch up paint that matches with a brush..lol seen it done and to where paint isnt need but gotta make sure the powder doesnt contaminate the weld,good welder can tell

Again bung needs to be same material

 

[Dono]

I found an aluminum 6an bung on summit also (The factory valve covers appear to be aluminum). I was hoping to save shipping costs and do my order once I know pushrod size, but I think I'll order tonight. As I'm getting closer to getting my short block, Im realizing there is lots I should be doing in preparation.

 

[jd4242]

Nice..im in same boat now i got my motor out,got a little more fab before new motor is done and will fit..

Cant wait to see what that turbo does once new short block is in..

Also was talking to my buddy last night about pcv crap and he said and has a thing that screws into where his fill cap goes..it does all like you saying but drains any oil right back down into the fill neck..it was pretty crazy looking..his is a turbo Subaru

 

[Dono]

I just had a look on rockauto to see if I could find it on one of the turbo motors. It must be a factory only item. I have all the parts ordered (Besides the bung), and think its going to work out to be a good system. I'm going to run with it. The system is a closed system unless I'm in to boost, and that's really only a very small percentage of the time being my daily driver.

 

[jd4242]

O yea definitely sounds like you got it figured out and honestly it all confuses me and i didnt really understand him..but just texted him and he said its aftermarket and called

Grimmspeed air oil separator.

 

[Dono]

Ah yes, I looked at that product. This product needs a vacuum source.
It won't work for me (being rear mount turbo) as I have no vacuum source under boost to draw from at all.

 

[jd4242]

Gotcha..swore he said it worked just like normal pcv under no boost and shut when under boost..plus it would separate oil and drain back into motor when off..but idk lol

 

[Dono]

Gotcha..swore he said it worked just like normal pcv under no boost and shut when under boost..plus it would separate oil and drain back into motor when off..but idk lol

That is what he said, no question. Its the rear mount turbo that makes me need the hobbs switch and electric solenoid.
If the turbo was under the engine bay, I'd be able to have a closed system by porting in-between the maf (Pre-turbo) and the turbo. I can't do this due to the distance I need to run (To the back of the truck) and the reconfiguration issues I would have. Running a line to the back of the truck also runs me in to possible moisture issues in the winter that I don't need (vent lines getting plugged).

as 4pointslow put it, it appears to be the Achilles heal of a rear mount turbo. Definitely some draw backs to this type of system.