General: 850: Volvo 850 Air Box Mod - Seriously GREAT Sound

[BackInBlack]

Originally Posted by mario850

you see the way i am looking at it is if you have cut the snow gaurd away in the same way as in i now get the air being forced down the air pipe like a ram air and have noticed as its topend is better than before so cutting holes in the air box when the snow gaurd is cut away will just cause the air being forced in to escape through the holes rather than being forced in to the engine see my point

I do & that's a very good point, BUT in a way the 'ram air effect' is slightly useless with a stock air box because the engine will only suck in what it can as the stock air filter restricts the 'ram air effect'. I do fully understand what you mean though, you mean the air is is being rammed into the air box and in turn creating enough air inside the air box when needed, eg. WOT. If that is the case surely if I reconnect the front piping as to create the 'ram air effect' the air will rush into the air box and even if it does disappear away through the holes at least the air box is now receiving a fresh supply of cooler air when needed. I might be wrong entirely here, but with holes inside the air box there would be more throttle response at the lower rev range (to a certain degree) & with the air pipe ducting reconnected there would also be more torque at the high end speeds (with the snow-guard removed) as there is more air being rammed into the air box area. Could I say this is the best of both worlds... probably not as most people here will disagree with me entirely just to be 100% correct and have their poke too. I am sure they will say ... No you have it totally wrong, hot air will be sucked in, BUT <<<<< I repeat! BUT<< they never say at what speed. My car is practically moving 85% - 90% of the time when I am on the road. I don't have a job that involves traffic routes and most roads on my journeys are good long stretches (not as long as USA I know, but temperatures here arn't as hot as USA either).

A little question here. If you are getting the 'ram air effect' into the air box surely your also sucking in water into the air box when it rains? Surely.

[mario850]

thats what i thought after i cut up the snow gaurd but checked and its always dry after it been raining also the ram ai effect will only work with a sports filter as there is too much restriction on a standard one

[BackInBlack]

Originally Posted by mario850

thats what i thought after i cut up the snow gaurd but checked and its always dry after it been raining also the ram ai effect will only work with a sports filter as there is too much restriction on a standard one

Excellent Thanks

[s.hammond]

Originally Posted by mario850

you see the way i am looking at it is if you have cut the snow gaurd away in the same way as in i now get the air being forced down the air pipe like a ram air and have noticed as its topend is better than before so cutting holes in the air box when the snow gaurd is cut away will just cause the air being forced in to escape through the holes rather than being forced in to the engine see my point

i see what your saying, but it doesn't quite work like that becuase there's a vacuum the air will follow that along with the air being sucked in through the holes abit like if cut holes in the bottom of a straw you'll still suck up your drink throught the holes and the end becuase of the vacuum created by you sucking on it.

again this has been proven on a rolling road.

cheers.

[s.hammond]

Originally Posted by BackInBlack

I do & that's a very good point, BUT in a way the 'ram air effect' is slightly useless with a stock air box because the engine will only suck in what it can as the stock air filter restricts the 'ram air effect'. I do fully understand what you mean though, you mean the air is is being rammed into the air box and in turn creating enough air inside the air box when needed, eg. WOT. If that is the case surely if I reconnect the front piping as to create the 'ram air effect' the air will rush into the air box and even if it does disappear away through the holes at least the air box is now receiving a fresh supply of cooler air when needed. I might be wrong entirely here, but with holes inside the air box there would be more throttle response at the lower rev range (to a certain degree) & with the air pipe ducting reconnected there would also be more torque at the high end speeds (with the snow-guard removed) as there is more air being rammed into the air box area. Could I say this is the best of both worlds... probably not as most people here will disagree with me entirely just to be 100% correct and have their poke too. I am sure they will say ... No you have it totally wrong, hot air will be sucked in, BUT <<<<< I repeat! BUT<< they never say at what speed. My car is practically moving 85% - 90% of the time when I am on the road. I don't have a job that involves traffic routes and most roads on my journeys are good long stretches (not as long as USA I know, but temperatures here arn't as hot as USA either).

A little question here. If you are getting the 'ram air effect' into the air box surely your also sucking in water into the air box when it rains? Surely.

the answer is no the rain won't be suct in the ram pipe even if it was it won't be heavy enough to cause you problems, but if go through a solid body of water i.e ford or flood too fast then your in trouble!!!

hope this answers your question.

[HULK]

Originally Posted by BackInBlack

Last week I cut 8 big holes in the bottom/side of my 850 air box with little enjoyment. When I put my foot down all I heard was a deep 'boomy' noise. That is NOT the noise I'm after. I am after that 5 cylinder growl (I'm sure you know what I'm on about).
So I got under the hood, removed the air box and cut smaller holes but more, more & more. I remember reading on the net (after cutting the large holes) that the bigger the hole the more 'boomy' the sound. Okay my mistake for the first try. But now.... Yeeehaaa.... All I hear is that fiery beast under my hood wanting to escape. (Under heaver acceleration) Insane!!!
The acceleration feels more responsive, no extra gains in higher gears but certainly in 1st, 2nd & 3rd. It feels like it really wants to move now.

This seems to be the best and safest way I could do this. As you can see in the pictures the pipe coming from the air box to the front has been removed, this is only because I cut off the snow-guard (As shown in this forum before) and fear water getting in.
So far after driving for a week in heavy rain there has been no sign of water even near the air box(good news). I have also removed the silver exhaust manifold heat pipe. I wouldn't need that silver pipe as the y shaped plastic piece housing the air box flap has been completely removed...Not needed at all.

So today I thought I would take a few pictures of my 'holy' air box and share my enjoyment with the 'world'.


Enjoy....


I take no responsibility if you decide to do this modification. I doubt you would be unhappy, but you may not be happy in the end... YOUR CALL, NOT MINE!! You have been warned. ONLY MODIFY THE AIR BOX UNDER THE AIR FILTER, NOT ABOVE... Again take your time and be careful.

if you want that deep growl forget the air box
you are just going to suck in hot engine bay air.
fit a powerflex top engine mount. that will give you the sound you want.

[BackInBlack]

Originally Posted by HULK

if you want that deep growl forget the air box
you are just going to suck in hot engine bay air.
fit a powerflex top engine mount. that will give you the sound you want.

Now that would have been a whole lot easier. Wow, the routes I take.

Well the powerflex would have been excellent but not knowing this 2 months ago I got Volvo to replace my old one with a new genuine Volvo one.... Damn. Maybe some other time

[HULK]

Originally Posted by BackInBlack

Now that would have been a whole lot easier. Wow, the routes I take.

Well the powerflex would have been excellent but not knowing this 2 months ago I got Volvo to replace my old one with a new genuine Volvo one.... Damn. Maybe some other time

replacing the top engine mount is an easy thing to do yourself.
simplest mods there is. and only £20

[AcidicDavey]

Originally Posted by HULK

if you want that deep growl forget the air box
you are just going to suck in hot engine bay air.
fit a powerflex top engine mount. that will give you the sound you want.

I don't know much about these kind of mods so I have to ask how does this change the sound?

[HULK]

Originally Posted by AcidicDavey

I don't know much about these kind of mods so I have to ask how does this change the sound?

basicly it holds the engine still creating a very noticable and great sound.
when i changed mine i didnt no it changed the sound so i was very suprised when my car sudenly sounded the way it did.
i was amazed in the sound diferance just from changing a simple engine mount but it realy does make a huge diferance.