R33 fuel setup

[Blakeo]

Hi guys,

I have a R33 that I'm redoing the fuel system on. 

Currently it had a hack job by a tune shop that they have cable tied the braided lines under the car and jerry rigged a stock hanger to use two pumps.

I've redone the fuel tank with a frenchy performance twin pump setup, have ordered custom brackets for the fuel lines.

My question;

I am running AN8 feed and AN6 return.

On the fuel rail is it normal to have an8 fitting on one side and the an6 on the other?

I also noticed my ethanol sensor on the return is only 5/16 instead of AN6, should I look at running it parallel or it won't be an issue?

[Dose Pipe Sutututu]

Do both sides the same, and yes parallel the ethanol sensor.

[Blakeo]

1 hour ago, Dose Pipe Sutututu said:

Do both sides the same, and yes parallel the ethanol sensor.

Thanks Dose.

Is this how you would do it:

Please excuse the horrendous diagram, I can't help it I drive a Nissan.

[Dose Pipe Sutututu]

Put the FPR, after the fuel rail but before the Y split.

If not, fuel will find the path of least resistance and bypass the FPR.

Another option is, new 8AN feed, then use both the original feed/return as dual return (that's what I did).

[Blakeo]

4 hours ago, Dose Pipe Sutututu said:

Put the FPR, after the fuel rail but before the Y split.

If not, fuel will find the path of least resistance and bypass the FPR.

Another option is, new 8AN feed, then use both the original feed/return as dual return (that's what I did).

Makes sense, just not sure how to put the ethanol sensor in parallel after the fpr.

[Dose Pipe Sutututu]

1 minute ago, Blakeo said:

Makes sense, just not sure how to put the ethanol sensor in parallel after the fpr.

You could do it underneath the car (I personally don't like this ideal).

Mine is in the boot, but it's also on the pressure side from the main tank to the surge tank.

[Blakeo]

Just now, Dose Pipe Sutututu said:

You could do it underneath the car (I personally don't like this ideal).

Mine is in the boot, but it's also on the pressure side from the main tank to the surge tank.

I just saw one of these bad boys: https://www.radiumauto.com/Split-Flow-Flex-Fuel-Sensor-Adapter-P2194.aspx

Looks to be perfect solution.

[GTSBoy]

^That is a good thing. But it was never going to be any harder than putting a T piece and elbow either side of the flex sensor with a piece of -4 or -6 in parallel.

Probably end up costing more with all the fittings, so that Radium thing is probably the right answer.

[Dose Pipe Sutututu]

The radium thing is sexual.

[TurboTapin]

Racetronix also sells those ethanol content sensor bypass blocks. Adapter, Flex-Fuel E85 Sensor High-Flow Bypass, In-line No Sensor (ADF-FLEX-NS): Adapters - Flex Fuel | Racetronix

Ethanol content sensor are originally designed to be on the feed line. These bypass blocks are meant to be ran in the feed line and not return. The continental ethanol content sensors have a 3/8" ID and not 5/16". This is why they are ran on the return line directly in conjunction with a low threshold sampling value VS in the feed with one of these blocks. 

 

On 12/30/2024 at 10:02 PM, Dose Pipe Sutututu said:

Put the FPR, after the fuel rail but before the Y split.

If not, fuel will find the path of least resistance and bypass the FPR.

Another option is, new 8AN feed, then use both the original feed/return as dual return (that's what I did).

Haha we think alike, I used both original feed/return for 8AN feed, and one of the Hicas lines as a 6AN return. I also capped off and left the other Hicas line as a spare. 

Edited Wednesday at 02:22 AM by TurboTapin

[r32-25t]

I used the radium thing, makes the whole parallel assembly a lot more compact compared to any other way of doing it 

[Dose Pipe Sutututu]

8 hours ago, TurboTapin said:

Haha we think alike, I used both original feed/return for 8AN feed, and one of the Hicas lines as a 6AN return. I also capped off and left the other Hicas line as a spare. 

I was actually being a tightarse at the time LOL...

My OCD is tickling me into running a 2nd 8AN Teflon hose all the way down and removing the 2x OEM hardlines. My other side of my brain is telling me to run 2x hardlines front to back (also acts as a fuel cooler, so win win).

[MBS206]

10 hours ago, Dose Pipe Sutututu said:

I was actually being a tightarse at the time LOL...

My OCD is tickling me into running a 2nd 8AN Teflon hose all the way down and removing the 2x OEM hardlines. My other side of my brain is telling me to run 2x hardlines front to back (also acts as a fuel cooler, so win win).

My first thought is run hardlines, but running a soft pipe is easier and quicker, though normally more exxy...

[WR33KD]

Hard line it, you will be thankful later on, if you car had hicas, use that as your return. 

[GTSBoy]

Hell yeah. It's not as if the path from front to rear is particularly squirrelly or otherwise difficult.

[MBS206]

1 hour ago, GTSBoy said:

Hell yeah. It's not as if the path from front to rear is particularly squirrelly or otherwise difficult.

It just depends if you're like me with a high level of OCD for doing something like hardlines, and highly critical of the little things, and then bugger all patience to get it how my brain pictures it

[GTSBoy]

I just quote the Rolling Stones.

Paint it black.