Testrun

I did not verify the issue is fixed. I took it for a quick spin and got into the boost a little. It does seem to be running a couple/few points richer. That's 16 gauge through the bulkhead. It has 2 16 gauge for power and 2 16 gauge for ground plus the stock wiring. One ground is too a bolt in back of hatch and the other is to the fuel hangar. That has to be enough wire for the supra pump.....

and damnit no I didn't check the O ring!!! I don't see how that can be the culprit considering it only does it when something gets hot.

At least I didn't cross the wires up in tank lol

The gauges will be a week away before install probably. Life keeps getting in the way.

cr-rex

iTrader: (114)

The cars are old.... standard logic doesnt always apply

Testrun

Ok so I just wanted to update you guys. I re wired the pump inside the tank.

The whole map was rich.... mostly under boost and I mean stuttering rich. I started with just about a full tank of gas and ran to just under 1/4..... the damn thing does the same only this time it took much longer to do it. After about 6-7 20 min sessions it started to run lean..... WHAT THE BLOODY HELL!!!!!
I didn't hook up my fuel press gauge like an ahole, but I can tell you mid way through the sessions the exterior of the fuel tank stayed like warm.... at the end the tank was hot to the touch. So it is definitely heating up.
So I guess at this rate I will be changing the supra pump for as walbro that flows as much or more at the same amperage? I will change my bosch 2200s out for some ID 1300s or 1700s, and if that doesn't work the only other thing it could possibly be is it needs bigger fuel lines.. I do recall one GTR having problems with these injectors getting too hot and making it lean out later in the dyno sessions. Definitely something to consider.
I know this thing could be kicking a lot more power than I had planned, but I still see no way it could be over doing the lines.

This makes me wonder how many other cars are out there with the same issue..... guy tunes car to where it is perfect and kicking ***..... never gets too meticulous as to run close to empty or give something time to heat up. After awhile on the track or hard back roads she starts slowly running lean and costs an engine. Mayne not right away from something popping, but gradual over time the EGTs just get too hot.
I didn't build this car to have to keep it above 1/2 a tank. This is very frustrating.

I know, I know I need the fuel pressure gauge up. I should have done it already, but I the same stuff will be needing replacement regardless.

dguy

iTrader: (8)

It's the difference between building a car with intention and calibrating the fuel system/ECU and just slapping parts together and having some other dude come in and 'tune' it. The amount of money that people waste on tuning these days is astounding.

Testrun

This build was thought out and done with purpose. Nothing on this build was purposely "slapped together". Maybe I was misled by some of the "gurus" or guys that have been around for awhile when it came to selecting my injectors or rail, but other than that I see nothing "slapped" together for a 350whp build which was the original intent. I just happen to be a bit over at 13-14psi I guess which is a good thing.
I am tuning it myself with a program and so far it is better than what some "professional tuners" have done. Anyway, I will figure it out one way or another, but again at this stage what is there to replace? Pump, injectors, or lines.... or all 3 unless I am really missing something.

Testrun

I should add that voltage is fine back to the bulk head. There is no reason for it not to be in tank.

cr-rex

iTrader: (114)

Did you remove the o-ring seat from the top of the pump?

Testrun

No I did not. You think it could be heating and swelling?

Cr-rex at this stage if I could get a greater flowing pump with less draw I think it would benefit.

cr-rex

iTrader: (114)

remove this method pf transfer and replace it with a piece of SUMBMERSIBLE fuel hose and re-test. you will need to cut the pipe on the hanger. this is what youre going for

Testrun

I think I will keep the Supra pump as it has to be more than enough at 280-290lph, but I will take your suggestion and put the hose on. I got it from Banzai and they supplied both ways to hook it up. I should still have the hose somewhere.
I will install the fuel pressure gauge and most likely will swap injectors as stated before for some ID1700s.
If pressure is messed up I will move to the next step of a different rail and a fuel pressure regulator I guess. I will go with radium so I can keep the fuel temp and have no issues with the 1700s.
BTW, even if the fuel is heating up isn't that why we have a fuel temp sensor to compensate?
My inj vs temp is
+20° 1.00
+40° 1.020
+60° 1.039
Maybe it still isn't enough to compensate.
I will do above said and check back in.

cr-rex

iTrader: (114)

The percentage is so small on the temp correction that its basically negligible. 2-3% is really small especially considering the Temps the fuel has to reach for that correction to trigger. I believe for this reason the fuel temp sensor is left out of majority of aftermarket rails. Its really negligible and if you're at a point where you need aftermarket rails, that 2-3% compensation is picked up somewhere else in the tune anyway. Its seriously not worth the time or space unless your circumstance actually benefits from it for some reason. I can't think of a real reason that fuel temperature would need to be monitored or a correction be put in place for it. Just seems like some really oem stuff when you're trying to make a car for a somewhat global climate/market.

cr-rex

iTrader: (114)

Double post.... oops

dguy

iTrader: (8)

It wasn't meant to be a dig, I was illustrating that there are a lot of people that end up thinking that their car is built like a tank and then have a respected tuner come by and do some work when in reality there are always issues that crop up. Building a car in its entirety is a far more comprehensive endeavor which is why when someone comes to me to have me do work/strap it to my dyno I have a laundry list of questions that I feel the need to ask and most of the time I can't get actual answers.

DaleClark

iTrader: (55)

I believe the fuel temp sensor in the fuel rail is less there for ECU map corrections and mainly for hot starts.

With the car shut off hot and heat soaked the fuel can boil in the fuel rail. The ECU sees the high temp and will bump fuel pressure up for a hot start, letting the car start more easily. FC's had this problem a lot of times with hot starts.

That's what the rat's nest solenoid that's tied to the FPR is for. Normally it's vacuum/boost to the solenoid, when it kicks in it's atmospheric pressure which, at idle, will bump fuel pressure up.

Dale

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Logs indicate 13.5v at wot from time to time........ damnit.

Somehow I missed that even watching the voltage with a meter. That can be a big issue....

cr-rex

iTrader: (114)

more importantly....... fuel pressure. theres a correction table for voltage but there isnt one for fuel pressure

Testrun

I kind of feel like a dumbass and am most likely making this more complicated than it is.

I never updated my alternator. I ran into a few "upgrade your alternator posts" and just thought ... damn. Really? I am running a bigger pump (denso, but still some bigger amperage), aem water inj, ignition amp, and it is hot as hell here in south fl. I keep the stereo off while tuning of course, but the amps are still on.

Any one ever mess with a alternator diode? I hear you can get another .3-.5 volts. I don't really recall hearing about this on the forums. I will probably send mine to IRP.

cr-rex

iTrader: (114)

an electrically overloaded system would be easy to diagnose. log batV or just watch it as you drive. more importantly, you need to fix the o-ring situation at your fuel pump

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O ring will be done asap!

scotty305

iTrader: (2)

My car's alternator failed earlier this year. It had about 95k miles on it. I'm waiting for a replacement from IRP, I ordered online but there was some confusion as to whether they were waiting for my core. In short, if you order online it's a good idea to call a couple days later to make sure everything is on track.

Testrun

Thanks Scotty. Yeah I was thinking ahead about that. Seems a little pricey, but I haven't looked into alternators for years so it could be normal.

scotty305

iTrader: (2)

The other alternative I looked at is by DCPowerInc, which costs more. It looks like they use guts from a newer/better alternator inside a custom case that fits our cars. A stock-equivalent replacement looks cheaper than the IRP, but I liked the idea of upgrading. Be careful with the bolt that holds the alternator bracket to the water pump, mine had corroded and seized pretty badly.

Testrun

I do not it want his post to die as it may help others in the future. I did install the 140 amp alt. The problem does actually still exist, just took longer before it started and more gradual.
I still did not hook up FP gauge, but wanted to just stop in and say it is improved, but not totally. Anything between 1/4 tank and 1/2 tank or more there is no issue. It is solid as a rock.
Will post the results of the Fuel Pressure soon.

cr-rex

iTrader: (114)

thats crazy.... but still havent replaced that o-ring attachment? damn......

its crazy because that fuel level just so happens to be about the height of the o-ring. if its leaking there then it would be less noticeable since it would just suck in gas from the leak instead of through the pump.

Testrun

Lol I know man... it will get done. I just though I may have been on to something as it was in the logs.
Next move is....
1. O ring removal and install the hose technique
2. Fuel pressure gauge