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post #16 of 73 (permalink) Old 04-10-2006, 12:04 PM
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Quote:
Originally Posted by Malekreza11
dont drill te hole, and dont flip no nozzle.
doh!! TE's instruction said to use a .94mm bit to make the hole in the jet valve bigger. Their picture also showed that the jet valve is flipped around....

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post #17 of 73 (permalink) Old 04-10-2006, 03:07 PM
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Quote:
Originally Posted by NaFooEsi
doh!! TE's instruction said to use a .94mm bit to make the hole in the jet valve bigger. Their picture also showed that the jet valve is flipped around....

Attaching original TE instruction image:

yea, dont do what the instruction manual says... Dont drill the Jet valve too large and dont flip the Jet valve nozzle either.

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post #18 of 73 (permalink) Old 04-10-2006, 06:23 PM
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Quote:
Originally Posted by Malekreza11
yea, dont do what the instruction manual says... Dont drill the Jet valve too large and dont flip the Jet valve nozzle either.

Wish we knew that beforehand! LOL. You figure...there are instructions and you would want to follow them right? Wonder if these instructions were from the great IS300GTE's legacy where he proclaimed omipotent understanding of all things cars.

The way that you guys have done it seem easy and straight forward...it literally would work the exact same way as stock when done as such. Wonder why TE/IS300GTE thought they needed to mod it further?

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post #19 of 73 (permalink) Old 04-16-2006, 11:59 AM
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As I'm currently doing this project ....
I am plugging up the stock FPR shown in pic above as #3.... nevermind 'm trying to reinvent the wheel. just follow above instructions

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post #20 of 73 (permalink) Old 04-16-2006, 02:02 PM
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Quote:
Originally Posted by TeCKis300
Wish we knew that beforehand! LOL. You figure...there are instructions and you would want to follow them right? Wonder if these instructions were from the great IS300GTE's legacy where he proclaimed omipotent understanding of all things cars.

The way that you guys have done it seem easy and straight forward...it literally would work the exact same way as stock when done as such. Wonder why TE/IS300GTE thought they needed to mod it further?
I don't believe either one of these effects pulling fuel from the other side of the hump.

Drilling out the Jet valve allows your fuel sensor to read alittle more accurately.

Moving it simply moves it.

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post #21 of 73 (permalink) Old 04-19-2006, 11:53 PM
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Quote:
Originally Posted by lambchop11078
Here's what you need to do to the fuel pump assembly.

1. Drill a hole in the plastic fuel pump assembly.
2. Get a bulk head fitting and install the fitting on that new hole.
3. Install the return line from the FPR to the end of the fitting that's exposed.
4. The other end of the fitting that will be in the tank needs to connect to the white ventricle.
5. Cut the line that's connected between the stock FPR and white ventricle.
6. Either pinch the nipple that is now exposed on the stock FPR closed and weld it shut or get 1/4" fuel line, 1/4" bolt that has no threads on the shoulder. Cut off the threated area of the bolt, insert the bolt in the 1/4" line and put a hose clamp on it. Put the other end of the rubber line on the stock FPR.
6. Run rubber line from the bulkhead fitting to the end of the white ventricle that the stock FPR was connected to.
Question??????
WHY ?
I did steps 1-3and 5, I JB welded the Fuel Pressure Regulator shut. and also shut where the FPR use to plug into. What I don't know or understand is why do I need (step 4,6 )to conneect from the fitting to the white ventricle. why can't I let it just freepour into the tank. from whta I see by blowing and sucking into the white ventricle it just re-routes but does nothing more. Am I missing something very important? I have driven the car maybe 50 miles and it doesn't act up. is it building pressure or something to do with the passenger tank that I don't realize?

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post #22 of 73 (permalink) Old 04-20-2006, 11:40 PM
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You need to have the return fuel flow through the contraption because it is the mechanism that will draw fuel from the other side of the tank. It works based on Bernoulli's Principle. The return flow of fuel essentially creates a low pressure region within the contraption which will draw fuel from the other side of the tank. Without this, you car will still work fine. You will just loose about 4 usable gallons that you can't draw from the other side.

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post #23 of 73 (permalink) Old 04-20-2006, 11:50 PM
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Quote:
Originally Posted by SophieSleeps
I don't believe either one of these effects pulling fuel from the other side of the hump.

Drilling out the Jet valve allows your fuel sensor to read alittle more accurately.

Moving it simply moves it.
Drilling out the Jet valve has nothing to do with the fuel reading!

I think the rumors of non-working fuel gauges has to do with the early pioneers that didn't know how to use the fuel draw contraption which meant they couldn't get access to the last 4 gallons of fuel. This lead them to think the fuel gauge didn't work. If you set it up right as shown in this thread...you should most definitely have a working fuel gauge.

There has also been rumors of the stock ECU calculating fuel level from MAF/injector duty cycle. While I believe the ECU does use it to some extent, as an engineer...this is counter intuitive. You would never derive a reading when there is an actually float that can give you the true value.

So change the injectors/standalone/tuning all you want. Get the jet valve contraption right and you will have a working fuel gauge!!!

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post #24 of 73 (permalink) Old 04-20-2006, 11:59 PM
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Quote:
Originally Posted by NaFooEsi
doh!! TE's instruction said to use a .94mm bit to make the hole in the jet valve bigger. Their picture also showed that the jet valve is flipped around....

Attaching original TE instruction image:
Jason,

I don't remember exactly how u put this together...but I think you have the draw line on the wrong fitting. Is your draw line on the middle jet valve fitting? It needs to be on the other short one. If it is...the return fuel is going straight to the other side of the tank.

Also, put the thingy back in the stock orientation. If the jet valve is not above the "cup thing" underneath it catching the return flow, the jet valve will be aerating the fuel in the tank which you don't want.

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post #25 of 73 (permalink) Old 04-21-2006, 12:06 AM
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Drilling out the jet valve would probably be beneficial to you guys that are running much higher flow rates as the stock small orifice would be limiting the return flow rate, building pressure in the contraption and nullfying Bernoulli's Principle.

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post #26 of 73 (permalink) Old 04-21-2006, 01:48 AM
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Quote:
Originally Posted by TeCKis300
There has also been rumors of the stock ECU calculating fuel level from MAF/injector duty cycle. While I believe the ECU does use it to some extent, as an engineer...this is counter intuitive. You would never derive a reading when there is an actually float that can give you the true value.

Counterintuitivity aside, did you see my testing that resulting in me saying the MAF reading is very important?

1) MAF completely unplugged. Car/tranny in limp mode, gas gauge drops by 1/4 tank increments regardless of the float gauge

2) MAF plugged in, but wrapped in a rag in engine bay (not in air intake stream, just hanging). No limp mode, but gas gauge still drops by 1/4 tank increments. No love from float gauge.

3) MAF plugged in and installed in air intake. Dead on accurate gas gauge.


Unless the car was throwing a code for MAF voltage out of range, which for some reason bypasses the float gauge and disables the gas gauge, the MAF has some important function here... but it's not the most important thing.

I think you're probably right with the saddle tank thing and it's effects on early gas gauges.

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post #27 of 73 (permalink) Old 04-21-2006, 02:02 AM
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DAS: but this means that the ecu is also reading/modding the floater readings - Did you try to do the same, but see if there is a fuel pump pinout that would say "I'm sending info about the fuel level to the ecu" or vice versa "the ecu is sending info about how much fuel should be left in the tank"? - just curious, as I actually had this in mind...

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But I think for most people "fine" is usually good enough.
For power hungry people "fine" isn't going to cut it.
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post #28 of 73 (permalink) Old 04-21-2006, 02:10 AM
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Quote:
Originally Posted by TeckniX
DAS: but this means that the ecu is also reading/modding the floater readings - Did you try to do the same, but see if there is a fuel pump pinout that would say "I'm sending info about the fuel level to the ecu" or vice versa "the ecu is sending info about how much fuel should be left in the tank"? - just curious, as I actually had this in mind...
Didn't go beyond the MAF, since once I plugged it back in and had a gas gauge I was golden again.

Whatever it is, for the tank to drop by 1/4 increments is pretty drastic. They obviously don't give a lot of credit to that float gauge... it seems like it's only an emergency backup for the MAF or some other calculation that is only used every 1/4 tank.

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post #29 of 73 (permalink) Old 04-21-2006, 07:49 AM
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Quote:
Originally Posted by dasgalloway
Didn't go beyond the MAF, since once I plugged it back in and had a gas gauge I was golden again.

Whatever it is, for the tank to drop by 1/4 increments is pretty drastic. They obviously don't give a lot of credit to that float gauge... it seems like it's only an emergency backup for the MAF or some other calculation that is only used every 1/4 tank.

Das, I saw your thread and yes, I agree that the MAF does play a role like I mentioned. However, I believe the float is the primary sensor and the MAF is secondary. The MAF is the load sensor in terms of instantaneous gas usage but the float will still determine your absolute gas level.

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post #30 of 73 (permalink) Old 04-21-2006, 11:43 AM
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Quote:
Originally Posted by TeCKis300
Das, I saw your thread and yes, I agree that the MAF does play a role like I mentioned. However, I believe the float is the primary sensor and the MAF is secondary. The MAF is the load sensor in terms of instantaneous gas usage but the float will still determine your absolute gas level.
Would be interesting to disconnect the float and watch only the MAF calculation to see how accurate it is then....

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