Air box mods

[threedogs]

I think there will be pretty good gains wiv what ur wanting to archive with ur intended mods to airbox.. Not a zd30 but I'm pretty sure this is what u want.. 3 inch streight frm airbox lid to turbo but with the the original maf housing modified to be part of that particular intake system... Keep up the good work and let us knw how u go.. Cheers mullet..

Attachment 56122

You hit the nail on the head ,not bad for a chippy lol
That original photo shows all he's done is replace the OE tubing with 63mm,
looks neat IMO

Can someone explain why the billet HPD MAF sensor is better than the OE,
I can understand a larger throttle body, Please explain,,,,,,,,,,,

[mudski]

Can someone explain why the billet HPD MAF sensor is better than the OE,
I can understand a larger throttle body, Please explain,,,,,,,,,,,

I'll try to explain the best I can here....
The slightly larger I.D allows more air to pass over the MAF. The MAF has a sensor plate which heats up from power running through it, more throttle = more power, and gets cooled by the air passing over it. I don't know how to explain it technically as I'm not auto sparky, but the heat produced on the plate gets converted into voltage (or something along the lines of that) and is read by the ecu. If this voltage goes over a certain limit, you see limp mode. So having a larger I.D housing, allows more air to pass over the MAF at the same throttle rate.
So say if there was 200cfm of air going over the maf at 3000rpm with the stock housing. With the larger i.d at 3000rpm there would be 250cfm of air. (those figures aren't actual...) So more air at the same throttle response.

[threedogs]

Stock intake is only 63mm I think so if thats right an OE MAF housing might be say 55mm the HPD is now equal to
the OE piping at 63mm, [for comparison only]so the HPD is equal to the OE piping, there abouts
That being the case if I fit a MAF housing in a 63mm or 76mm pipe for that matter then I've acheived the same thing.
I propose putting the MAF about where the OE one is.
I think when volts reach 4 volts on the MAF you'll hit limp mode

Surely this HPD MAF housing on its own cant do much
its only 50mm long and you're using the existing plumbing
you either need to up grade the OE piping or go bigger again like I want to.
To Mark and MH can you say your Patrol goes faster/better because of this mod.

[mudski]

Stock intake is only 63mm I think so if thats right an OE MAF housing might be say 55mm the HPD is now equal to
the OE piping at 63mm, [for comparison only]so the HPD is equal to the OE piping, there abouts
That being the case if I fit a MAF housing in a 63mm or 76mm pipe for that matter then I've acheived the same thing.
I propose putting the MAF about where the OE one is.
I think when volts reach 4 volts on the MAF you'll hit limp mode

Surely this HPD MAF housing on its own cant do much
its only 50mm long and you're using the existing plumbing
you either need to up grade the OE piping or go bigger again like I want to.
To Mark and MH can you say your Patrol goes faster/better because of this mod.

Dr Gary had issues and he went out and bought the HPD maf housing and he's loving it now. It's proven this housing does what it's designed too. As for your question John. If you just put this housing in and do nothing, you won't see jack chit in performance. It's only when you start to raise the boost you will find you won't see limp mode. This is what this housing is designed for. Don't get it confused with bolt on performance, where you install it and then go wow. It's only designed to eradicate limp mode issues.

[mullet_hunter]

Dr Gary had issues and he went out and bought the HPD maf housing and he's loving it now. It's proven this housing does what it's designed too. As for your question John. If you just put this housing in and do nothing, you won't see jack chit in performance. It's only when you start to raise the boost you will find you won't see limp mode. This is what this housing is designed for. Don't get it confused with bolt on performance, where you install it and then go wow. It's only designed to eradicate limp mode issues.

Well said.. its not like a bolt on extra hp mod.. it allows u to run higher boost levels with out limp mode.. ie u can run double factory boost which means lower egts and higher performance through out rev range.. mine pulls hrd in 3rd and i can see upto 28 psi on the gauge... but im pretty sure ur intended mods will see similar results.. cheers mullet

[threedogs]

just find it strange thats all When the MAF holder arrives from MH I'll measure the inside diameter.
Whats the inside diam. of the HPD unit ??
Just saying as you only get more air over the width of the HPD unit
before that air is travelling through OE size piping
and after is OE size piping, so if that was the case if I could increase
the diam of the OE maf housing I've acheived the same thing.
Also do you use the OE MAF sensor or do HPD supply one

found a length of exhaust bandage [new] in my shed so decided to bandage up the boost hose for the IC
maybe it will keep the incoming temps to the IC down a bit.
Held it in place with some stainless steel "cable ties"

@ mudski cause of my set up I dont think it will hit limp mode,

[mudski]

HPD maf housing dont come with a maf.... Your current setup John, don't bother with the Larger maf housing. You wont achieve anything apart from wasted time. Just concentrate on the pipe to the turbo.

[threedogs]

If I can incorperate an OE MAF into a larger diameter Pipe it should do the same as the HPD unit.
I have two options one is 63mm back to the OE MAF which is easy enough to do.
Option 2 is new lid and run 3" and reduce to 63mm at the turbo end,with the MAF in the 3" pipe
What the heck I'll do both and see what makes the difference if any

[threedogs]

http://www.ebay.com.au/itm/301560290...%3AMEBIDX%3AIT

This mesh looks very restrictive on the OE air box lid [see link], plus I think there is another on the MAF housing
removing that would allow heaps more air in.

[paulyg]

I have removed those mesh screens and I have a HPD maf housing, it does what they claim.
But remember it will lower your maf voltage a little bit, so you may loose performance if you don't retune.