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Discussion Starter #1
Hey guys

LSA swap. Trying to make a 5inch intake. But space is limited.

Struggling to fit a 5inch filter so I was considering a Turbo guard.

Alternatively I can run my filter like below but I believe it will heat soak like a MOFO.

Also MAF placement. There are no straight sections. It’s a 5” 45 degree pipe and no room at all if I go the filter option.

Where is best placement? Or can I ditch it and use IAT sensor like the old school LS1 Mafless tunes?


Thanks.
 

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Hey guys

LSA swap. Trying to make a 5inch intake. But space is limited.

Struggling to fit a 5inch filter so I was considering a Turbo guard.

Alternatively I can run my filter like below but I believe it will heat soak like a MOFO.

Also MAF placement. There are no straight sections. It’s a 5” 45 degree pipe and no room at all if I go the filter option.

Where is best placement? Or can I ditch it and use IAT sensor like the old school LS1 Mafless tunes?


Thanks.
I would see if I could extend the tube with a straight piece for a MAF. Cut a hole and use the bend to put the filter into the fender well.
 

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Discussion Starter #3
Managed to get it to fit. I’ll get the MAF welded into that pipe in the middle.

Best I can do.
 

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A honeycomb airflow straightener in front of the MAF might be a good idea...

http://www.saxonpc.com/100mm-cells-for-100.html

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This. While experimenting with my intake "back in the day" those honeycomb units did the trick. Read the guidelines on how to choose the right size holes and thickness tho. But they work great and ensure.

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Any bends in front of the MAF may affect, especially if it's close. It appears you may have an inch or 2 in front of the MAF depending on where you weld the maf bung. If 2 inches, def get the honeycomb. It can only help

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I was looking at these early days. Sadly I don’t think I’m going to have the room for this. Will having a card style MAF on the back of the 45 be an issue?
You do what you want but the smaller the ID the less straight length you need.

It’s called upstream and downstream pipe diameters in the industrial flow measurement world.

The honeycomb is a type of flow conditioner that shortens the necessary straight lengths, but does add pressure drop, so your power potential does decrease.

Not saying how much, as I don’t know, but from a purely mathematical perspective it absolutely has to account for a power loss.

If you are using VE, it doesn’t matter, but using the MAF the less than ideal locations does affect the ability to dial the tune in faster and with better results.

This is one reason I see little value in going beyond a 4.5” intake.




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Discussion Starter #9
You do what you want but the smaller the ID the less straight length you need.

It’s called upstream and downstream pipe diameters in the industrial flow measurement world.

The honeycomb is a type of flow conditioner that shortens the necessary straight lengths, but does add pressure drop, so your power potential does decrease.

Not saying how much, as I don’t know, but from a purely mathematical perspective it absolutely has to account for a power loss.

If you are using VE, it doesn’t matter, but using the MAF the less than ideal locations does affect the ability to dial the tune in faster and with better results.

This is one reason I see little value in going beyond a 4.5” intake.




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Yeah I remember reading something along those lines on this forum ages ago.

I’m just a plumber....maths ain’t my best. But it makes sense what your saying.

What’s the VE your speaking about?

If there is alternate way I’ll take it. Realistically I just need the MAF to get my engineers cert so I can register the vehicle on the road. Once it’s registered I can start modifying things etc.

So if this VE thing will work I’d go that path.

Just for now. It needs a maf
 

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Discussion Starter #11
Volumetric efficiency. Speed density method
Ok. So would this require additional sensors etc?

I kinda wanna make my intake once but then again don’t want 15 different bungs and sensors hanging off it.

But if it comes to it I’ll make a real cheap and dodgy one that gets me by.

Another thing intake related is a bung for catch can.

I have an old style MM unit. But confused on best way to run my lines.

It has 3 ports in total. One has the internal tube which I’m told is for the PCV.

ONE port is meant to have a clear view bung.

Do I loop both valve covers and run them to the open port on the catch can and then the PCV port back to the intake?

I’m used to old school chevs and Holdens where everything is just vented to atmosphere.
 

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The honeycomb filter just smooths out airflow for a more accurate MAF reading.

You dont change the sensors, just add the honeycomb to make the existing MAF more accurate.

The bigger the pipe, the less air speed and the less accuracy for MAF sensor values. The honeycomb just helps offset that by smoothing out airflow. But the honeycomb is technically a restriction is what he was getting at.


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Correct. Placement of maf and airspeed are both necessary for signal strength.

No extra sensors required.

I often wonder if those that design their own intakes care where they put the MAF, if using one?

Not only does location matter, but so does orientation (in plane or out of plane).

Feel free to google that, it should keep you busy ;)


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Good rule of thumb with these airflow smoothing devices so you don't have to do ANY math is:

You need about an 8:1 ratio of thickness to diameter of the holes. So if the holes are about 1/8 inch in diameter then you need the thickness of the inset to be about 1 inch.

So the smaller the holes, the thinner it can be. And don't forget it must be upstream of the MAF sensor.

I've used one in a 4.5 inch intake with a tight turn and it did the trick. Done right this has a minimal impact on airflow.

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Something to keep in mind with airflow, in the pic below your airflow (and speed) is going to be the highest where that red arrow points, right next to the tight inside bend. Conversely, the airflow (and speed) will be the lowest on the opposite side where the bend is larger. Either of these two locations independently will provide a wide variation in MAF signal output.
 

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A properly designed intake should not need any smoothing inserts
This. My post is not intended to endorse anything. But if your intake has been modified (as mine had) then this may be a decent option.

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This. My post is not intended to endorse anything. But if your intake has been modified (as mine had) then this may be a decent option.

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I think, in your case, you had a tuner that perhaps didn’t have enough skill in the part throttle and transient fueling areas and the honeycomb bandaid helped overcome some of the deficiencies. He was very adept at maximizing power on the dyno and even on the dragstrip, so I’m it’s not like I’m not giving credit where credit is due, but perhaps less so from a driveability standpoint.

There are only a handful of timers that do both well...my 2 cents.


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