Air filter placement.

[Tempted]

Agreed. A properly sized filter will be almost no restriction.

It comes down to efficiency though. If you can get the same power from a filter half the size then it is more efficient. Since any filter under pressure will flow better than it would without pressure, it makes it more efficient. It cleans up the engine bay a little as well. After I get some better looking parts on it I'll post some pictures.

If you are suffering from power loss due to filter size it makes more sense to me to use the same filter under pressure than just buy something bigger. Is there a filter that we can fit under our hoods that will flow well enough to handle 500hp without costing any efficiency. What that means is if you make 500hp with the filter, would you make more without it? If so then that filter is obstructing flow.

[GLHNSLHT2]

If I lose 5hp running a filter before the turbo vs. ruining the turbo by having dirt, leaves, water etc go through it then so be it. If this is about all out power and the last .001 of a second on a race track it's still not an argument because you just run no filter at all.

[Tempted]

Not sure how a leaves would get past wire mesh, but okay. Also not sure how misted water will ruin a turbo either. The thing I'm trying to determine is how much more efficient this can be. The fact is a turbo doesn't require highly filtered air like an engine does. If the turbo inlet is mounted in a fender like most are, it will most likely never have an issue even without running any type of pre-filter. But if I can eliminate the cold side starvation by putting the filter under pressure, and then use a less restrictive filter on the cold side inlet, I can increase the overall efficiency. That means power, fuel mileage and longevity. The harder a turbo has to work to pull air in, the less efficient it is and the less gain you will see in terms of HP. Putting the filter after the turbo means it doesn't have to overcome any pressure difference. Any small, high flow large pore foam or plastic will be enough of a filter for the turbo and will have a more or less neutral effect on volume intake.

I'm unsure why people seem so agitated right now. All I did was ask if it had ever been tried to see if it was already proven or disproven. In theory it should work but until I get to a dyno I won't know for sure. My initial impressions are that the turbo seems to spool faster and the total output seems the same, apart from getting to that output faster.

[shadow88]

So before you hit the rollers, can you be sure to have a properly sized filter?

[turbovanman²]

Not sure how a leaves would get past wire mesh, but okay. Also not sure how misted water will ruin a turbo either. The thing I'm trying to determine is how much more efficient this can be. The fact is a turbo doesn't require highly filtered air like an engine does. If the turbo inlet is mounted in a fender like most are, it will most likely never have an issue even without running any type of pre-filter. But if I can eliminate the cold side starvation by putting the filter under pressure, and then use a less restrictive filter on the cold side inlet, I can increase the overall efficiency. That means power, fuel mileage and longevity. The harder a turbo has to work to pull air in, the less efficient it is and the less gain you will see in terms of HP. Putting the filter after the turbo means it doesn't have to overcome any pressure difference. Any small, high flow large pore foam or plastic will be enough of a filter for the turbo and will have a more or less neutral effect on volume intake.

I'm unsure why people seem so agitated right now. All I did was ask if it had ever been tried to see if it was already proven or disproven. In theory it should work but until I get to a dyno I won't know for sure. My initial impressions are that the turbo seems to spool faster and the total output seems the same, apart from getting to that output faster.

No ones agitated, we are simply questioning why someone for the sake of say 5whp, so add 1 psi of boost to make up for it, would be willing to destroy an expensive turbo for the sake of a few hp.

This summer, somehow my intake pipe came undone, I didn't notice until a few days later, my turbo is right at the back, I managed to suck in sand/dirt and some small rocks as the intake tube was dirty and when I inspect my compresssor wheel, it was slightly damaged.

[Tempted]

Of course, if you just take the inlet tube off and let the turbo spin free you will suck up all kinds of trash. But if your inlet pipe would have been routed in the fender it probably wouldn't have been hurt at all without a filter.

So before you hit the rollers, can you be sure to have a properly sized filter?

The question becomes what properly sized means. My intentions are to hit the rollers with the same air filter, just in different locations. This will eliminate the question of the difference in the filters.

[shadow88]

http://www.turbo-mopar.com/forums/sh...nts&highlight=

This is what properly sized means. Calculate your airflow requirements, then go about 100 cfm over that to make up for restrictions that come from dirt accumulation.

Don't get me wrong, I would like to see your testing show positive gains, but for anything to be fair, you have to have the correct sized filter, or the "with and without air filter test" will be wasted. Not only that, but you should go on the rollers expecting your filter placement system frist to regate any gains from the subsequent runs and the magical 5 or so hp that comes from the gains after a warm engine is reached.

[Tempted]

Some of us have motors capable of very big numbers. We all know an engine is an air pump, so the bigger the numbers the bigger filter we need to provide clean air. There comes a point when space turns into an issue, especially with a FWD car. When you also consider that very large filters don't fit in the areas that have the coolest, cleanest air(fenders/grills) it means you have to place the filter where is can fit, usually right next to the hot engine.

I don't know that this will work. It might cause me to lose power. I just tend to do a lot of theoretical thinking and when something seems like it could work on paper, I want to try it in action.

I did run into an issue today, though. I tried to use a larger, better built filter and it didn't clear the intake. When I produced that drawing a few days ago I placed the filter on the top with the IC hoses inverted. I didn't do that on the car. I'm thinking that I might have to actually invert the hoses and place the filter higher up, just like that picture. It means I'll need to get creative with IC piping and that almost always means worse flow characteristics since it adds air direction changes. I can clear the issue completely by either mounting the small factory intercooler in front of the core support, or just going with an upgraded aftermarker piece.

If this is proven to work, the benefits are actually great. The hose and pipe routing will look much cleaner, for one, but also being able to use a smaller area to draw the intake air into the turbo will be nice. This means you can get to the cooler air in small pockets that a normal filter won't fit.

One of the facts that can't be disputed is that a filter under pressure will always flow more than an atmospheric filter. Its why fuel pumps and oil pumps are not filtered before the pump, they are inline and under pressure. Its easier on the pumps as well if they only have one force to overcome rather than two(a filter before the pump means that the pumps must both draw the fluid in under strain and push the fluid out under pressure). Again though, this is just based on theory so I could be way wrong.

[GLHNSLHT2]

yea all the sand that somehow accumulates on the kframe or inside your airbox. If you think Mesh is going to stop a leaf need to think again. A dried up leaf will hit that, crumble and go right through your turbo. Go ahead, do your test. Come back in 10k miles and show us your compressor wheel.

---------- Post added at 04:17 PM ---------- Previous post was at 04:10 PM ----------

Some of us have motors capable of very big numbers.

Dude you better know who you're talking to before talking like that with 42 posts. The 2.5 I am building is "capable" of some of the biggest TD #'s out there. I'm still going to run a filter before the turbo. If my 4" outlet filter isn't big enough oh well.

[Tempted]

yea all the sand that somehow accumulates on the kframe or inside your airbox. If you think Mesh is going to stop a leaf need to think again. A dried up leaf will hit that, crumble and go right through your turbo. Go ahead, do your test. Come back in 10k miles and show us your compressor wheel.

The chances of me putting 10k miles on a single turbo are nil. Especially a stock one. I know what a turbo can and can't do, as well as what can damage it. Most damaged impellers are caused by user or equipment error that would have been prevented with simple periodic inspections.

Dude you better know who you're talking to before talking like that with 42 posts. The 2.5 I am building is "capable" of some of the biggest TD #'s out there. I'm still going to run a filter before the turbo. If my 4" outlet filter isn't big enough oh well.

What are you going on about? I'm talking about engines in general, not just common blocks. I said "some of us" because everyone on this site is a car guy, not only a TD guy. No point in singling out just one. The "Dude you better know who you're talking to before talking like that with 42 posts." comment really necessary? I wasn't aware that post count determined one's knowledge but if it does then I'll be glad to link you to my profiles on the other 2 dozen automotive forums I'm a member of. I'm also a vendor in most of them. I assumed that this forum, being mostly occupied with owners who drive classics, would be a little more mature than that comment shows.

You seem to be trying to pick a fight. If the setup doesn't interest, just move along. No point in getting offended by it. I see the potential behind the theory and that is why I'm trying it. If everyone thought that the best designs had already been established then we would never get another improvment or game changer. I appreciate input and reasoning, just not fruitless remarks. If this had already been tested and proven to fail then I'd move on to something else. If it hasn't and there is a potential for improvement, why not try it?

"I have not failed 1,000 times. I have successfully discovered 1,000 ways to NOT make a light bulb." Thomas Edison

Imagine what would be if he just accepted the then assumed fact that candle light was the best way to see in the dark.

[cordes]

Why can't you get 10K out of a turbo? I've gotten at least 150K out of one of mine.

[Tempted]

Why can't you get 10K out of a turbo? I've gotten at least 150K out of one of mine.

I didn't mean I can't, I meant that I change them often. I'm a tech but when I'm not repairing something on a ticket I'm usually screwing with something on one of my vehicles. I've always got some kind of goofy project going on.

[shadow88]

I just don't want to see you spend the time and money to try to test your ideas and not cover all the variables before hand. I'm sure you can find some way to fit the proper sized filter.

[Tempted]

Absolutely, I'm doing my best to cover all bases before potentially frying an engine but no matter what there will always be an inherent risk when trying something not tried before. I prefer the idea of a smaller filter if it can prove to be adequate. If it can't then I'll go with the standard options. I'm in no way concerned with destroying a turbo based on contaminates. I do not plan on keeping the wire mesh as the prefilter, I have the intentions of using a foam or plastic screen with extremely large pores. It will prevent the things that can damage the turbo from getting in, but will flow far far more than an actual air filter. The inline filter will catch the things that the screen will miss that might damage the motor. My only question is the actual gain or loss it causes. If the gain is minimal and I have room for a filter large enough, I'll go that route. If the gain is measurable then I'll keep it. The worst thing that can happen is I kill an old stock T3 Garrett. Not a real loss. With the inline filter in place, pieces of the turbo can't enter and damage the engine.

[shadow88]

What would you consider a worthy gain? Have you thought of what order to do your dyno testing?

[Tempted]

A worthy gain would be a measurable peak HP output, but what I am hoping for is to hold a more consistent powerband at an earlier engine speed. I am not after peak numbers as much as I am complete numbers. A 600hp motor is great but if it doesn't make the power before 5000rpms on an engine that redlines at 6000, its useless. If I can get peak turbo CFM faster then I'll consider it a success.

I'll most likely make 2 pulls per set up, in reversed order. Meaning inline, no filter, atmospheric filter in that order for the first time, then let the car settle back down and reverse the order the second time.

[turbovanman²]

The chances of me putting 10k miles on a single turbo are nil. Especially a stock one. I know what a turbo can and can't do, as well as what can damage it. Most damaged impellers are caused by user or equipment error that would have been prevented with simple periodic inspections.

Or debris, errosion,

[John B]

This 3" BY 10" S&B is what I'm using on a 3" Spectre Hose. What do you think?

[Tempted]

Where did you put it?

[John B]

Where did you put it?

The filter is where the battery used to be and the inlet pipe goes straight down to the turbo inlet. The turbo inlet is 3" so I don't figure I'd gain much going larger. Wrong?