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Where To Plug Map Hose?

ARTZ

By ARTZ,
in Engines & Forced Induction

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ARTZ Grand Master

ARTZ

Posted
Posted

ok just a quickie..ECU has built in MAP so all i have to do is run a hose to the manifold..

Now instructions told me to put a T-piece to the boost reference port on the reg which is what I have done...and it works..

But I am a bit worried about the hose running along the fuel rail as I have noticed it gets quite hot..i have put it inside some of that plastic conduit with the injector loom but not sure if this is a great idea either..

Im wondering if it is better to just plug it in at the back of the manifold, maybe where the boost gauge is or something...

Or is there any reason it SHOULD stay connected to the fuel reg reference pipe ??

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Dale FZ1 Veteran

Dale FZ1

Posted
Posted

is there any reason it SHOULD stay connected to the fuel reg reference pipe ??

No.

Your instructions are written as a guide. FPR takeoff is from a convenient point in the plenum, and the guide just helps pick up a convenient point.

Use a decent quality type hose and you can sheath it and/or cable tie it to stop it chafing or subject it to heat etc if you want. Bottom line is to use a hose-spec that's not going to be affected by heat, and protect it/route it away from exhaust pipes/manifolds.

The suggested pickup is only for somewhere to get a reliable MAP signal.

SargeRX8 Grand Master

SargeRX8

Posted
Posted

Between your manifold and BOV is good. Between your FPR and manifold is good but not suggested, if somehow that line in any way gets damaged you will lose pressure which is applied to your FPR to help raise fuel pressure. ie you will run lean if you somehow split the line going to your ECU. I think the best place to get the boost reading from is right infront of your turbo. You have the boost reading as is, straight out of the turbo. Route it through the driver side rather than passenger side, there are cleaner ways to get in on the driver side in an R33.

blind_elk Grand Master

blind_elk

Posted
Posted
I think the best place to get the boost reading from is right infront of your turbo.
That doesn't give "manifold" pressure (MAP = Manifold Absolute Pressure). It certainly doesn't give manifold vacuum. On boost, it will tend to spike and drop back.

The best place is off the manifold.

SargeRX8 Grand Master

SargeRX8

Posted
Posted

That doesn't give "manifold" pressure (MAP = Manifold Absolute Pressure). It certainly doesn't give manifold vacuum. On boost, it will tend to spike and drop back.

The best place is off the manifold.

Yeah after reading it, you are right. I would hook my boost controller where I said initially and hook the MAP sensor to any line running directly off it(to the BOV, FPR) or you can always tap one into it.

ARTZ Grand Master

ARTZ

Posted
  • Author
Posted

so the boost gauge port on the back of the manifold is no good??

hose is tucked neatly with the wiring loom that runs along the firewall to the ECU so it will be fine there..its just running it under the intake plenum I dont like...

GTSBoy Grand Master

GTSBoy

Posted
Posted

so the boost gauge port on the back of the manifold is no good??

hose is tucked neatly with the wiring loom that runs along the firewall to the ECU so it will be fine there..its just running it under the intake plenum I dont like...

Absolutely. Afterall, the sensor that is already connected to the back of the plenum is a MAP sensor......

HYPED6 Collaborator

HYPED6

Posted
Posted

OK...... Um...... I'm no expert but.........

The Map sensor line for your ECU should be installed on the most reliable map source on your engine so it does not receive pulsing from the inlet manifold.

Any where in the center of the plenum away from the runners if possible. Some ECU's with very fast map sensors and very poor filtering will see every pulse and make it hard to tune.

I have seen as much as 4-7 psi variation from poorly installed map lines.

DO NOT put it with anything that bleeds air. EG, boost controller. As this will drop your reference psi.

I recommend putting it with your fuel pressure reg. This makes sure that if it does come of, your engine is guaranteed to run like a bucket.

This will make you look further.

If you have a boost gauge then this can work well too. It gives you a visual if the sensor line has some off. (less vacuum/less boost)

gotRICE? Veteran

gotRICE?

Posted
Posted (edited)

I used the small VAC port on the back of the plenum on my RB25 with Link G4. Its the same size as the MAP sensor on the board so does make sence.

Doesnt cause me any dramas.

And im pretty sure link suggest to stay away from FPR and BOV lines. Just being cautious i suppose. Id rather it have its own vac supply personally.

This way you just run it along the brake lines on the firewall and through the grommet under the ABS :) Easy done.

Edited by gotRICE?
ARTZ Grand Master

ARTZ

Posted
  • Author
Posted

^^^yeah thats what i thought too..i already have a t-piece in my boost gauge and the stock gauge is still running, I figure i just use this line that is going to the stock gauge cause I dont really need it..as hyped said that way I have a visual as well...

89CAL Grand Master

89CAL

Posted
Posted

^^^yeah thats what i thought too..i already have a t-piece in my boost gauge and the stock gauge is still running, I figure i just use this line that is going to the stock gauge cause I dont really need it..as hyped said that way I have a visual as well...

Yeah id do this. That way your boost gauge and ecu should always see the same boost. I have my boost gauge and controller reading from the one port (both using map sensors) and they work fine

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