Does a cold air intake add power on a 4.0?

reddvltj said:
Not trying to be obtuse. The reason I am asking is, the stock air box, in the Jeep I recently picked up, had been replaced with a Banks intake setup. I know I can find an OEM airbox and tube to put back in, but I'm planning on doing something that is more suited to high clearance fenders, similar to some of the mods that have been done by others in the forum. I already have ABS pipe and fittings readily available, so what I'm asking is, would there be a detriment using ABS over polyethylene or polypropylene?
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I am not 100% on which plastic they use other than I know what it isn't which is ABS which is the most easily glued of all the plastics a DIY would work with. Lot of folks have fabricated stuff to the factory air box and tube with any normal glue failures reported including myself which is the only way I know what it isn't.

I wouldn't use ABS purely due to the wall thickness of the pipe and the easily identifiable nature of the fittings as being for something not normally found under the hood. That is only my personal bias and no reflection on the viability of using said parts.
 
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Zorba said:
Seems to me that an easy way to prove that the air filter is the major restriction would be to do two back to back dyno runs, one with, and one without the filter...
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I think you could also put a pressure probe in the intake tube. Compared to MAP would tell you if/when the TB becomes a restriction and compared to barometric would tell you about the air filter.
 
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And paper can handle higher temps than most plastics. Just have to make sure the glue can handle it. The wall is a bit thin on a pringles can. Maybe try a carpet core tube?
 
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reddvltj said:
Not trying to be obtuse. The reason I am asking is, the stock air box, in the Jeep I recently picked up, had been replaced with a Banks intake setup. I know I can find an OEM airbox and tube to put back in, but I'm planning on doing something that is more suited to high clearance fenders, similar to some of the mods that have been done by others in the forum. I already have ABS pipe and fittings readily available, so what I'm asking is, would there be a detriment using ABS over polyethylene or polypropylene?
Click to expand...

Per the 2-3 letter symbol they imprint on most plastics used in the automotive industry (and elsewhere), the air box is polypropylene.

1690336814024.png




https://en.wikipedia.org/wiki/Resin_identification_code
 
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mrblaine said:
Per the 2-3 letter symbol they imprint on most plastics used in the automotive industry (and elsewhere), the air box is polypropylene.

View attachment 444509



https://en.wikipedia.org/wiki/Resin_identification_code
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Ok, it's 20% carbon fiber, reinforced polypropylene. Probably why it doesn't like to play well with most glues or welding sticks.
It'd be interesting to see if this would work with the CF reinforced PP.
permanent bond
https://www.gluegun.com/products/mm...c-bonding-mma-adhesive?variant=40145761796249
non-permanent bond
https://www.gluegun.com/products/in...lastic-bonding-glue-stick?variant=44846933764


https://www.gluegun.com/blogs/news/best-adhesive-for-bonding-polypropylene-pp-and-polyethylene-pe
 
reddvltj said:
Ok, it's 20% carbon fiber, reinforced polypropylene. Probably why it doesn't like to play well with most glues or welding sticks.
It'd be interesting to see if this would work with the CF reinforced PP.
permanent bond
https://www.gluegun.com/products/mm...c-bonding-mma-adhesive?variant=40145761796249
non-permanent bond
https://www.gluegun.com/products/in...lastic-bonding-glue-stick?variant=44846933764


https://www.gluegun.com/blogs/news/best-adhesive-for-bonding-polypropylene-pp-and-polyethylene-pe
Click to expand...

The CF isn't the problem, it's the PP. Flame treatment helps.
https://theepoxyexperts.com/flame-treatment-plastic-substrates-adhesive-bonding/

Or it can be welded.
 
@reddvltj just looking at the melting temps of abs and pp doesn’t tell the whole story. They are very different materials, in that abs is amorphous and pp is semi-crystalline. What it does to their heat resistance is why that is important. As abs get warmer, it also softens, linearly with heat, until it’s a puddle. Polypropylene, because it’s semi crystalline will maintain most of its rigidity until it hits its melt point, then it rapidly becomes molten. Makes it a real bitch to ultrasonic weld, as your process parameters need to be really dialed in. ABS on the other hand is very easy to weld.

If you’ve ever belled the mouth on a piece of pvc pipe, ABS behaves the same. You can heat it to a point where it’s like modeling clay and stretch it. You can’t really do that with polypro. However, with both materials, you can plastic weld them together buy getting the pieces molten and letting melt flow together.
 
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Mike_H said:
@reddvltj just looking at the melting temps of abs and pp doesn’t tell the whole story. They are very different materials, in that abs is amorphous and pp is semi-crystalline. What it does to their heat resistance is why that is important. As abs get warmer, it also softens, linearly with heat, until it’s a puddle. Polypropylene, because it’s semi crystalline will maintain most of its rigidity until it hits its melt point, then it rapidly becomes molten. Makes it a real bitch to ultrasonic weld, as your process parameters need to be really dialed in. ABS on the other hand is very easy to weld.

If you’ve ever belled the mouth on a piece of pvc pipe, ABS behaves the same. You can heat it to a point where it’s like modeling clay and stretch it. You can’t really do that with polypro. However, with both materials, you can plastic weld them together buy getting the pieces molten and letting melt flow together.
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PP and PE hit the "molding point" at a slightly lower temp than ABS, unless it's glass fiber reinforced (PP-GF 30) then it's the same molding point. Something else pointed out by Blaine, which after some thought I agree with, is the massive difference in thickness of the different materials. The ABS would be much heavier in comparison and the joints wouldn't look good at all (hidious would probably be a better way to describe it)! Now that I know about the MMA 500 Ultimate Difficult Plastic Bonding, I'll probably start looking for some OE air tubes to see what it will take to sleeve them together. It'll be an adventure in success or futility.

MaterialsMold Temprature Range (℃)
ABS – acrylonitrile-butadiene-styrene40-80 / 104-176 (f)
ABS/PC Alloy40-80
PET (Amorphous)20-30
PET (semi-crystalline)20-30
Polypropylene (Homopolymer)30-80 / 86-176 (f)
Polypropylene (copolymer)30-80
Polypropylene (30% tank filled)30-50 / 86-122 (f)
Polypropylene (30% Glass Fiber)40-80 / 104-176 (f)


MaterialsMelting Point Range (℃)
ABS – acrylonitrile-butadiene-styrene190-270 / 374-518 (f)
ABS/PC Alloy245-265 / 473-509 (f)
PET (Amorphous)260-280
PET (semi-crystalline)260-280
Polypropylene (Homopolymer)200-280 / 392-536 (f)
Polypropylene (copolymer)200-280
Polypropylene (30% tank filled)240-290 / 464-554 (f)
Polypropylene (30% Glass Fiber)250-290 / 480-554 (f)
 
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reddvltj said:
PP and PE actually hit the "molding point" at a slightly lower temp than ABS, unless it's glass fiber reinforced (PP-GF 30) then it's the same "molding point". Something else pointed out by Blaine, which after some thought I agree with, is the massive difference in thickness of the different materials. The ABS would be much heavier in comparison and the joints wouldn't look good at all (hidious would probably be a better way to describe it)! Now that I know about the MMA 500 Ultimate Difficult Plastic Bonding, I'll probably start looking for some OE air tubes to see what it will take to sleeve them together. It'll be an adventure in success or futility.

MaterialsMold Temprature Range (℃)
ABS – acrylonitrile-butadiene-styrene40-80 / 104-176 (f)
ABS/PC Alloy40-80
PET (Amorphous)20-30
PET (semi-crystalline)20-30
Polypropylene (Homopolymer)30-80 / 86-176 (f)
Polypropylene (copolymer)30-80
Polypropylene (30% tank filled)30-50 / 86-122 (f)
Polypropylene (30% Glass Fiber)40-80 / 104-176 (f)


MaterialsMelting Point Range (℃)
ABS – acrylonitrile-butadiene-styrene190-270 / 374-518 (f)
ABS/PC Alloy245-265 / 473-509 (f)
PET (Amorphous)260-280
PET (semi-crystalline)260-280
Polypropylene (Homopolymer)200-280 / 392-536 (f)
Polypropylene (copolymer)200-280
Polypropylene (30% tank filled)240-290 / 464-554 (f)
Polypropylene (30% Glass Fiber)250-290 / 480-554 (f)
Click to expand...

Did you ever wonder how someone just casually happens to know a few things about the differences in how all this stuff works? That may be due to someone in another life being the engineer for automotive related molding of very high quality plastic parts. I wouldn't pass over his info lightly.
 
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mrblaine said:
Did you ever wonder how someone just casually happens to know a few things about the differences in how all this stuff works? That may be due to someone in another life being the engineer for automotive related molding of very high quality plastic parts. I wouldn't pass over his info lightly.
Click to expand...

It wasn't too hard to figure out he's at the very least, worked with said materials enough to know way more than I do. The where and how he gained his knowledge did excape me, but between what has been discussed here and what I've read thus far, I've bookmarked posts and websites, so I can come back to them when I do finally get to the point of needing to fabricate/cobble something together. I did at least give him the blue thumb of appreciation!
 
reddvltj said:
Ok, it's 20% carbon fiber, reinforced polypropylene. Probably why it doesn't like to play well with most glues or welding sticks.
It'd be interesting to see if this would work with the CF reinforced PP.
permanent bond
https://www.gluegun.com/products/mm...c-bonding-mma-adhesive?variant=40145761796249
non-permanent bond
https://www.gluegun.com/products/in...lastic-bonding-glue-stick?variant=44846933764


https://www.gluegun.com/blogs/news/best-adhesive-for-bonding-polypropylene-pp-and-polyethylene-pe
Click to expand...

If it matters, we were able to finally locate the same symbols on the lid to the air box and then the air horn. The air horn is just straight PP with no CF that we can find.
 
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mrblaine said:
If it matters, we were able to finally locate the same symbols on the lid to the air box and then the air horn. The air horn is just straight PP with no CF that we can find.
Click to expand...

From all that I could find on that bonding adhesive, the CF "shouldn't" make a difference so I'll give it a try first. I have been fairly successful welding ABS and some other thicker placstic formulations (not exactly sure what they were) but the thinner materials have given me enough headaches, it's probably going to take a better quality plastic welder to not end up burning holes in the material.
 
reddvltj said:
From all that I could find on that bonding adhesive, the CF "shouldn't" make a difference so I'll give it a try first. I have been fairly successful welding ABS and some other thicker placstic formulations (not exactly sure what they were) but the thinner materials have given me enough headaches, it's probably going to take a better quality plastic welder to not end up burning holes in the material.
Click to expand...

The 4 easiest to fabricate are vinyl, acrylic, styrene, and ABS. They have glues and bonding methods that are just basic and simple to do with just a bit of practice. There may be others but those are the ones I'm familiar with. I've hot air welded miles of vinyl and it is just time and temp.
 
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reddvltj said:
From all that I could find on that bonding adhesive, the CF "shouldn't" make a difference so I'll give it a try first. I have been fairly successful welding ABS and some other thicker placstic formulations (not exactly sure what they were) but the thinner materials have given me enough headaches, it's probably going to take a better quality plastic welder to not end up burning holes in the material.
Click to expand...

Looks like the Spectre Performance stuff is ABS for the 3" size

1690461593782.png


https://www.spectreperformance.com/accessories/8148-air-duct-mounting-plate





4" gets you the option of aluminum or ABS

1690461639582.png

https://www.spectreperformance.com/accessories/91489-intake-tube-duct-mounting-plate



1690461706956.png
 
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