Silicone hoses

peepsalot

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Contributor
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Black 03 MSP
Hey everyone, I just replaced my wastegate and bpv hoses with some nice silicone. People weren't even kidding about the brittleness of the stock hoses, I coudln't get them off some of the fitting, so I would just snap the hose in half instead. Anyways, I got this hose from this site, and I thought it was a pretty good deal.
http://boostcontroller.com/index.php?category=8

The 4mm is just slightly larger ID than stock, and I used some little zip ties to secure the lines on barb fittings. They are big enough to fit up to a 3/16" barb fitting, which is nice because I installed a golden eagle "vacuum manifold" which I could only find 3/16" barbs for.
 
I got black, everything in my car is black, don't like the flashy colors.

Yeah, there are only three colors, so it's not good for people that have to match a certain color scheme, but every other place I looked seemed pretty overpirced IMO.
 
Hose Techniques sells bulk hose in 3.5mm. Do you think that would be too small? Or do you think that would fit perfectly?

I'm asking since you seem to think 4mm was slightly too large...
 
3.5 is about as close to stock hose diameter as you can get. I just looked at some stock hose I have lying here. I think the actual diameter of it is in some strange fractions of an inch, but that doesn't matter.

I don't think 4mm is too big however. All the fittings you connect to have some sort of barb or hump that stretches the hose beyond that. And if you reuse the stock hose clamps or use zipties then there is no way it wold pop off or anything.

I have had the 4mm hose on my wastegate without a hose clamp or ziptie for a couple months now (boom01) It is quite snug though.
 
haha, i'm slow, i started typing that response like half an hour ago, then left my computer, came back and presed submit.
 
I bought the same hose this winter, and now that it's nice enough out I am going to replace the stock crap.

1 question though, do you have to match exact lengths? Does it matter if you put an extra inch or 2 in there?

Thanks,
Ryan
 
Length is not that critical except for maybe the wastegate, which works better with the shortest amount of hose.
 
peepsalot said:
Hey everyone, I just replaced my wastegate and bpv hoses with some nice silicone. People weren't even kidding about the brittleness of the stock hoses, I coudln't get them off some of the fitting, so I would just snap the hose in half instead. Anyways, I got this hose from this site, and I thought it was a pretty good deal.
http://boostcontroller.com/index.php?category=8

The 4mm is just slightly larger ID than stock, and I used some little zip ties to secure the lines on barb fittings. They are big enough to fit up to a 3/16" barb fitting, which is nice because I installed a golden eagle "vacuum manifold" which I could only find 3/16" barbs for.

bump, Peepsalot are you running a boost controller at all? If not, did boost change after swapping to the silicone hoses. I had an f'ed day. Car threw a cel so I reset it to see if it would come back. So I decided to pull the mbc of just because, and I snapped the plastic vaccum t thingey in the wastegate line. So ofcourse you have to trim it like a half inch. That's the 3rd or 4th time I've trimmed it. Long story short I don't have enough slack with that line any more and I'm tired of messing with it.
 
ND4MSP said:
bump, Peepsalot are you running a boost controller at all? If not, did boost change after swapping to the silicone hoses. I had an f'ed day. Car threw a cel so I reset it to see if it would come back. So I decided to pull the mbc of just because, and I snapped the plastic vaccum t thingey in the wastegate line. So ofcourse you have to trim it like a half inch. That's the 3rd or 4th time I've trimmed it. Long story short I don't have enough slack with that line any more and I'm tired of messing with it.
I am not running a BC, and I did not have a guage at the time when I changed out the hoses, so I don't know if it affected boost. I don't see any way that different diameter or different length lines would affect the maximum boost(as long as there are no leaks), since that is determined by the wastegate spring. It could however affect spool time or boost spikes possibly.

Like a friend of mine has a WRX, and they have a little restrictor that comes stock in the line on the way to the wastegate, it is just like a little plastic straight barb fitting, but changing it out for different diameters can affect spool time and boost spikes in some way. I don't know the details. They usually replace the stock(don't know the diameter) with a 3/16 fitting which some people think is ideal, so they call it the 3/16ths mod or something.
 
could someone point out exactly which hoses would benefit from replacement? i know all of em, but where in the engine bay are they?
 
They all start at the intake manifold, so follow any of the small diameter lines that connect to nipples on the intake manifold.
 
Yeah, except the one that goes to the brake booster, it's big. it comes from the middle back underside of the manifold, I don't know the exact diameter. You don't need to replace that one anyways, but it is technically a vacuum hose.
 
peepsalot said:
Yeah, except the one that goes to the brake booster, it's big. it comes from the middle back underside of the manifold, I don't know the exact diameter. You don't need to replace that one anyways, but it is technically a vacuum hose.

i tapped into my brake booster to feed my bov, btu since i'm going back to stock piping, should i just replace it?
 
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