R33Gtst->Need Boost Source (Evc)

[Torques]

Hello there,

For my Boostcontroller (EVC) I need a source that feeds the manifold pressure (so after the throttle) into the EVC.

(for meassurement of boost)

Apart from the nipple at the plenum (front face of it) is there anything I could use instead?

I don't want to route a hose there since it would not look nice

So any ideas?

Thanks ...

[JonnoHR31]

T it into the same nipple the standard boost gauge uses

[SargeRX8]

The stock Nissan one sits at the back of the engine bay I think. I just used the line to my FPR.

[JonnoHR31]

The stock Nissan one sits at the back of the engine bay I think. I just used the line to my FPR.

yes it does, hence why its perfect for routing into the cabin.

never ever ever T anything into the FPR vac line

[KerrodR33]

Why shouldn't you tee into the fpr line?

[Torques]

Thanks ... I will check the back of the manifold ..

[lachlanw]

there is absolutly no reason you cant T a map sensor into the fpr line .

not the blow off valve or pressure source or boost controller

tap it into the line at the back of the plenum for the factory boost gauge . while your at it throw the whole line away and replace it . its some weird hard plastic and its well known for splitting

[SargeRX8]

yes it does, hence why its perfect for routing into the cabin.

never ever ever T anything into the FPR vac line

Uhh but the greddy manual says to do this...

[JonnoHR31]

its just a bad idea in general. a map sensor might not create any issues but if you ever get any sort of leak/bleed on that line it'll drop fuel pressure under boost, which isnt good. theres plenty of other good spots to get boost references from

[DVS JEZ]

I agree with Jonno.the FPR line can be used but Its best to use a differen boost source when possible.

As he said if a boost leak occurs on that line the fuel pressure may drop and cause a lean condition

[SargeRX8]

That is actually the most logical and awesome reason not to use it. I seriously did not think of it like that, I always thought greddy suggested it as its closest to the plenum. lol out of paranoia, I will be changing mine.

[mattis96]

So how many things can you T off on 1 line?

[GTSBoy]

So how many things can you T off on 1 line?

You can tee as many things as you like. At some stage you may just be able to get enough length of 3 or 4mm bore hose attached to a single point that you can slightly delay the pressure signal by a small fraction of a second.

Think about it. There is no real flow in these lines. If they all go to MAP sensors or FPRs that just sense pressure, then there is no air going anywhere. All that happens is that when the plenum is under vacuum (and then so is the length(s) of hose off a tapping point) and you open the throttle and let boost in, then a small amount of air will cram into the hose(s) as the pressure rises. Then when you slam the throttle shut the opposite has to happen and a bit of air has to flow out of the hose(s) so the pressure can drop. But these sort of pressure pulses happen very very quickly. I'm sure the maximum number of such connections someone might want to make in a typical engine bay might be able to be counted on one hand, and so the total volume inside the litle hoses won't add up to much. And that's not even considering the possibility that some of the hoses might go to things that are mounted in the cabin and so could be 2m long. Still not going to add much delay to the signal.

BUT. If there is flow in the line, such as when you have a traditional boost controller with a bleed, then there is air flow in the line and you would be wise not to a) connect too many things together and b) connect things that might be upset by the leak (bleed), such the FPR.

[blk94r33]

I agree with Jonno.the FPR line can be used but Its best to use a differen boost source when possible.

As he said if a boost leak occurs on that line the fuel pressure may drop and cause a lean condition

Can someone clear this up for me? Does the stock GTST fuel pressure reg increase fuel pressure further if it sees above atmospheric pressure at the manifold? As in, a reg on a NA car operates at atmospheric pressure (wide open throttle) or lower,

[GTSBoy]

Can someone clear this up for me? Does the stock GTST fuel pressure reg increase fuel pressure further if it sees above atmospheric pressure at the manifold? As in, a reg on a NA car operates at atmospheric pressure (wide open throttle) or lower,

Absolutely. Whatever pressure is in the inlet manifold is the pressure that is applied to the FPR diaphragm. The only reason FPR signal can't go higher than 1 bar absolute is that the pressure in the manifold can't go any higher. Put a turbo on the same engine with the same FPR (ie just turbo the NA engine) and the FPR will now see whatever boost is applied to it and increase the fuel pressure by the same amount.