Supercharger install

[landtank]

I haven't followed every word as Sumotoy has been on my ignore list a few days and all I see is the cliff notes version when someone quotes him.

But is it possible that when the truck is WOT that the stock pump's flow rate can't keep up with consumption and the pressure in the fuel rail drops leaning out the AF ratio.

This is what I had gathered a while back and for my point that flow rate of the pump could influence PSI. If that's the case then only a pump with a higher flow rate could get the dead done.

Of course this could also mean excessive PSI in the rail if at low consumption if the return line restricted flow to influence rail pressure.

Sorry for the poor terminology as this is sort of new to me.

 

[SUMOTOY]

...

But is it possible that when the truck is WOT that the stock pump's flow rate can't keep up with consumption and the pressure in the fuel rail drops leaning out the AF ratio.
...

Anything is possible. What's more LIKELY is using basic math on RC engineering site, is finding quite simply that the stock FUEL INJECTOR FLOW RATE of 43.5psi rail fuel pressure at 80% DC can't keep up with consumption on a boosted motor. This is true even if you used 2 supra pumps and a 1/2in feed line to the rail!

You guys need to get on board with how fuel systems work. I urge you not to rely on toyotas to be bulletproof. Reread Christos post #6. His statement is absolutely dead nuts on. It's not 'automatic' to go to the Supra pump.

ST

 

[reffug]

Your welcome to your opinion.

X2..................

No I'm not gonna point you to any thread.

As I already stated use the search function.

 

[SUMOTOY]

X2..................

No I'm not gonna point you to any thread.

As I already stated use the search function.

Ok, that's fair enough, since I've already tried several searches in the last hour, just give me the keywords to use. The usual suspects got me nothing.

ST

 

[Cruisin'Carolina]

Holy crap I'm heading back into chat for a civilized discussion about politics and religion

 

[landtank]

Anything is possible.

So you don't know for sure. One thing I realised a while back is that your a text book engineering kind of guy. I've unfortunately have had to work with professionals like you and can tell you that while a book or web site might give you some insight into the real world it doesn't tell the whole story.

I personally respect most of the people on this site.

Christo claims that he doesn't need the Supra pump to support a turbo with greater fuel needs.

Others with the SC have seen a need for more fuel and claim the Supra pump works well.

So for a minute lets give these guys some respect and credit to their observations and digest this info for a minute.

So if the stock fuel pump can't keep up with the SC why can it then on a turbo with a greater appetite.

My conclusion is that there is a PSI drop in the fuel rail which will lean out on a SC but the extra injectors on Christo's turbo can deliver the needed fuel because the total flow through 8 injectors at the lower PSI is more than what's required.

So the only way to get the needed flow out of the 6 injectors is to increase the flow from the pump to maintain the fuel rail PSI. Which was the intended purpose of the Supra pump.

Now your concern is that the return line is restrictive enough to not allow the extra flow of the Supra pump to be bleed off to the tank during idling or other periods of low fuel consumption. This would seem to me to be a valid point and should be investigated.

T-ing into the return line just after the fuel reg. and reading the pressure at idle with the relay jumped to the high side would be the first step, right. Because if it passed this test then all possibilities would be covered.

Seems to me it's time to put down the pencil and paper and take some real world readings. I'd be more than happy to do this however I'm not in a place with my truck to help.


Then again maybe a 10 year old fuel pump is just weak with age and the new Supra pump is no better than a new stock one.

 

[cruiserdan]

Did I mention that I tossed my K&N?

 

[Romer]

Did I mention that I tossed my K&N?

No, was that you?


So I am convinced to get the full benefit of my Supra fuel pump I need to add the regulator. What specs should I look for? There are a lot on ebay.

I am still convinced by the difference in actual performances that it did make some benefit, probably due to what Mike and Rick have explained. But it is obvious the full benifit can't be achieved with out the regulator upgrade.

 

[clownmidget]

Ken, I don't know crap about piggy back fuel pressure regulators because I've had only one. I can say that BEGi is a very good company to deal with and I've got nothing but good experience and good things to say about them and their product. As I mentioned, I got the 2025 model. I've had it for a couple of years and actually just sent it back to Bell for a complete rebuild. Corky completely rebuilt it with all new upgraded parts that are used on the newest models and bench tested it. All that and turn around was 1 day. You can go to his site for prices as they are very, very reasonable IMO for such great treatment. I know you could find something cheaper on eBay but to me this is like supporting a vendor you appreciate for more than just the product.

I'll get around to re-installing the regulator and fuel pressure gauge over the weekend and can at least post some numbers - at least those for the components I have.

and man, my K&N is so dirty...

 

[landtank]

From my reading it looked to me tha the BEGi was a good choice. For our purposes there are two models to choose from. The 2025 and the 2027. The difference between the two is the fitting size. The 2025 has 1/8" npt fittings while the 2027 has 1/4" npt fittings. They typically go for around $260.00, just got a 2027 unused but 2 years old for $89.00. They seemed to be pretty scarce on there.

They also had a 2025 but at first clance I thought the fitting size would be an issue, however it seems that they have been installed.

 

[Romer]

which supporter is it? I don't know of them. I do ebay to see the variety, I would much rather buy from a supporter.

 

[Romer]

Mike,
He isn't here so I will say it for him

Did I mention that I tossed my K&N?

 

[landtank]

here is a 2025 on EBay

 

[sleeoffroad]

OK, you guys need to relax. In some way Sumotoy might be right on the possible rise in fuel rail pressure since the return can not flow the excess fast enough. This could be why Romer feels the truck runs better. Higher pressure in the fuel rail with injectors firing the same amount of time, means more fuel into the cylinders. This is a possibilty and without putting a fuel pressure guage on the fuel rail, all this is just speculation. Ken, you already have the pump, so one can install the guage and then read pressure at max demand.

We did the Supra pump a long time ago when we did a 93 truck where we ran a FPR. We added the pump since the stock pump could not maintain the prescriped pressure at WOT. With the Supra pump we could. Also, we needed to replace a 130k mile pump, so that was a logical choice.

On the 100 series we also replace the pump with a Walbro unit to ensure adequite delivery when the 2nd injectors come on.

On the last 80 we did not. It does not seem to need it. We can drown the car with fuel if we want to. Even at WOT.

So what did we learn from this, on a 93 truck with SC, with a flapper style airflow meter, we could get enough fuel into the system to run way to rich with a FPR and a bigger fuel pump. On the earlier trucks, the flapper slams open and the truck tries to put all the fuel in it can. It is just not enough.

We have not done a sc with fpr on 95-96 truck that has the different airflow measuring. They react better to the forced induction and does not lean out as easy.

Ken, I would suggest if you are going to start messing with this, spend the $300 on the AEM wideband guage. That is the only way to know what is going on. Adding a FPR blindly will not help if you don't have baseline data and even know if you need it.

RAMBLING OFF

 

[Waggoner5]

80 series pumps have worked really well on 2 V8 conversions I have done. Pressure was fine, delivery was fine. I am not saying that more would have been better, but at 320 hp they dyno tuned and road tested great. GM regulator took pressure down to 38psi at low load but rose to over 40 at high. You guys are are all ahead of the game, just doing things a little different. Nothing wrong with that. Ken, its got to be close to your bed time
G

 

[Romer]

Ken, its got to be close to your bed time
G

Aren't you funny careful or I'll sick Ige on ya


Christo, I am very relaxed. My truck also had almost 130K miles on it. Part of the reason I swapped it was the advice on someone we all respect that it would be a good idea to have a new pump with a SC at that mileage with freshly cleaned, valves, injectors and a new fuel filter. Since I was doing a new pump, it was suggested I might as well be the Supra Pump since it is capable of providing more fuel.

There are a lot of guys running the Supra Pump and the FPR. I PM'd/talked to a few of them prior to getting my SC and they all said the Supra pump was the way to go and kept the SC from leaning out. They had tried it with and without. I did not ask if they had any hard data. That's what I was poking at here, looking for data.

 

[Waggoner5]

I think I could take her.
If you are replacing, I would replace it with new stock, Although I agree with the arguement about the Supra pump, you probably are not going to be tweaking the engine much and stock really does work more than adequate.
G

 

[sleeoffroad]

How do they know it did not lean out?

 

[Romer]

How do they know it did not lean out?

That what I will have to follow-up on.

There are some fuel monitor data points that are accessible real time via the OBD II port.

Fuel System 1 (open loop)
Load Value
short term fuel trim 1
long term fuel trim 1

Would data from any of these help this discussion?

Could try it in mine, (SC Supra Pump), Sarah's (No SC stock Pump) and ask Kevin to try it on his (SC, Supra Pump, Fuel Regulator)

 

[clownmidget]

On the last 80 we did not. It does not seem to need it. We can drown the car with fuel if we want to. Even at WOT.

...with two extra injectors correct?

Can people agree that with the s/c'er bolted on and everything else, specifically the fuel delivery system, completely stock the truck will behave like it has leaned out under full boost/WOT (ie, ping/knock and have the ecu retard the timing)? I've experienced this on the 3.4-liter V6 s/c'er system prior to UnderDog Racing's efforts and TRD's post hoc addition of the 7th injector and on the 1FZ-FE's s/c'er. Since there is no evidence the stock injectors are incapable of flowing enough fuel at the upper end of their duty cycle to support that fuel demand under ~6 psi of boost there is a problem somewhere else in the fuel delivery system, no? That pretty much leaves the fpr or the pump. I know that another strategy is to just swap in larger injectors and get a whole different ecu to control them like a HalTech or whatever but in keeping it relatively simple and affordable the changing out of the pump and adding the piggyback fpr seem to allow you to control the high end lean, at least in my experience. Obviously adding extra injectors for Aquamist water/meth or fuel circumvent this but for the s/c'er crowd there aren't many that have done extra injectors...