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My 90 colt has a 92 tsi awd swap. It ran 13.0 at 106 mph with the stock injectors, fuel pump, maf, turbo, etc. It was definately maxed out though. It felt like it was making the same hp at 15 psi as it was at 20.
Now i just installed the 20g, maf translator, 560's, walbro 255. And it makes no difference whatsoever. I know i shouldn't expect much seeing as i haven't datalogged it yet, that is what's next. I have just been watching the wideband to make sure it doesn't go lean. i have no clue what the fuel trims are, or how much timing it has.

I installed the maft+ injectors before everything else, and it made no difference at all either. At that point, i thought the stock turbo was at its limit. It seemed to pull the same at 15 psi as it does at 20+.

It must be knocking like crazy.

Just putting on a bigger turbo and stuff like that isn't gonna do jack shit unless you run more boost and add more fuel. 560cc injectors are not big enough for a good-running 20g setup. I'd recommend at LEAST 660cc's or even larger.

yea you may be to lean, and the ecu is pulling a lot of timing to keep it from knocking. I would log a couple low boost pulls and work from there.

Hook up a logger and see if you're getting knock. Ditto on the injectors, you should be running 750's+ with a 20g.

You already know the answer, you need it tuned. I had wrote out more (but edited it) but after seeing you don't use a logger, there is no point. Buy a logger or take it and get it tuned, otherwise you are tuning blind. A wide band O2 is just keeping you from blowing it up.

To clairify a few things:
My personal best in a full weight GSX (3,100ish lbs): 11.1 @ 126MPH. With a 20G and 550's. Don't believe everything you read online...

Also, bigger turbo's are not for more boost. Well kind of, what they really let you do is make more boost more efficiently. A 20G at 15PSI will flow TONS more air than a 14b at the same boost while making less heat. More CFM, less heat = more HP. It's a weird logic, for for example, a 20G at 14psi, can make more power than a 14b at 16psi. Turning up your boost with a poor intercooler, or crappy cams, can make less power than you started out with. There's just WAY more to consider than the information you provided. My point is, a 20G in a 2,400ish pound car can easily go 130MPH+ in the quarter mile. Before you buy any parts, start with datalogging, see where your air flows are, injector pulse width/duty cycle, knock count, timing advance, etc are at, and go from there. Without that kind of information you'll be just throwing money at a problem you havn't even diagnosed. It seems as though that's what you have been doing up until now, and it obviously hasn't got you the results you were looking for.

Ryan

You were probably running race gas, right?

I was, but that has nothing to do with it at all. You boldly said 560's are not enough injector for 20G's, clearly, they were for me...

First I'll explain WHY I could do it:

I used a VPC / GCC, unlinke MAF translators or AFC's that manipulate the air flow signal to the ECU so to correct for extra air volume so that the ECU thinks the engine is operating in a normal state, un-aware of the extra fuel or air entering the engine. It's simple ratio's. You add 20% more air, 20% more injector, reduce the air flow the ECU see's by approximately 20%, and you have a reasonably happy engine and ECU. Much smaller injectors can be used in vehicles using stand alone ECU's or a VPC type computer that manipulates much more than air flow signal to achieve results.

To the "racegas" comment, although it does have a lot to do with why I could get a 3,100lb car to go 126MPH in the quarter, it has nothing to do with selection of injector sizing, at least not when compairing gasoline to racegas. All "gasoline" tpye fuels have roughly 114,000BTU's / gal. Various blends allow for some diviation, but more or less, that's where they all will be, regardless if it's 87 octane pump gas, or 118 octane C-16. To keep an engine for running to lean, you must add "X" amount of fuel per given amount of air. Explaining octane can be left for another day.
Now if we were talking about injectors required for a car running an alcohol based fuel, such as methanol, or ethanol, that would make a differance. For example E85, has a BTU rating of 81,000, or 71% of gasoline. That is why, as most of you know, vehicles will get anywhere between 20-30% fewer miles per gallon on E85, it's required that additional fuel be added to the engine (regardless of boost, compression ratio, etc, as it doesn't change in a flex fuel vehicle) to maintain propper air fuel ratio's. So you see, race gas really has nothing to do with it.
Ryan

So you don't think that by leaning a car out to run more aggressively on higher octane fuel has any effect on the injector duty cycle? Doesn't a lower octane fuel require MORE fuel to make the same "boom" than a higher octane fuel would? I still stand by my statement, I'm willing to bet you were well over 120% duty cycles on those 550's, which while you were able to get away with it, doesn't make it a good idea at all.

So you don't think that by leaning a car out to run more aggressively on higher octane fuel has any effect on the injector duty cycle? Doesn't a lower octane fuel require MORE fuel to make the same "boom" than a higher octane fuel would? I still stand by my statement, I'm willing to bet you were well over 120% duty cycles on those 550's, which while you were able to get away with it, doesn't make it a good idea at all.[/quote]

No, Sorry, you are 100% dead wrong. The "Boom" you are reffering to is the potential energy being released from gasoline by process of internal combustion. That energy is measureable, and absolute. In fact, I pointed it out above. There is only a negligible amout more energy (some times less) per measured ammount, that measurement being cc's, gals, pounds, or whatever in race gas compaired to pump gas.
OCTANE is actualy the measurement of RESISTANCE to ignition, specifically related to temperature and pressure, two factors that can ignite your fuel before the controlled ignition event (spark) causing pre-detonation or "knock". Octane has ABSOLUTELY NOTHING to do with amout of energy contained within a fuel. If your theory were correct, we would use E-85 (106ish octane) at much lower rates than pump gasoline (87-93 octane).
Although there are some minor details that make the finer points considerable for discussion, those details being varriables like specific gravity or oxygen levels within a particular blend, there is no "theory' that directly applies here. It's all physics. It IS what people would call "a science".
For whatever it's worth, although I wasn't running 120% duty cycle, that doesn't matter either.

So all that said, what would you like to bet as mentioned above?

Alright, so let's figure a full-weight GSX needs roughly 450whp to trap 126mph in the 1/4. I wanna see you make that much power on 93 octane fuel using 550cc injectors. GO!

Alright, so let's figure a full-weight GSX needs roughly 450whp to trap 126mph in the 1/4. I wanna see you make that much power on 93 octane fuel using 550cc injectors. GO![/quote]

That's not even a rebutal, that's a statement...
Now that we've taken this even farther off track, it takes 426 AWD HP, as measured on a dynojet, not 450. I happen to have data logs to show pusle width too, if we'd like further education.

If I must explain again, (and I will be breif for the sake of those who are understanding thus far) an Eclipse COULD go 126mph in the quarter IF appropriate means were used to keep away knock, created by increased combustion chamber pressure (why higher octane is required) created by additional boost, needed to add additional air, so we can add additional fuel to create additional power. That would require proceedures like water injection to cool the charge, larger intercoolers, an extreemly efficient turbo, etc. That is all because the MPH in a quarter mile is essentially a measurement of energy exerted by the vehicle (MPH), that can in turn be related to energy created (work) by combustion over a given length of time (HP and weight and distance), that can in turn be related the the energy in the fuel burned (BTU's). Boost simply allows us to stuff more air into a given motor over a given time, that additional air allows us to add additional fuel (energy), and all this creates the goal at the end. Horse Power.
That's it, I'm done, this conversation has been beat to death, those who don't get it by now, are not going to get it.

I'm not arguing with anything you're saying, which is why I wouldn't try to rebut you in any way. My "statement" still stands. I said that you trapping 126mph on 550's was made possible by running race gas. It's really that simple. Then you went ahead and made yourself look like a massive douche by trying to argue with me and sound all smart. You must look at yourself in the mirror and smile while you jerk off.

It is much safer for the OP to run larger injectors than to run on the edge with 550's.

Ryan and Tony, you are both correct to a point. Ryan, you are right about specific energy but Tony is right in saying that you likely wouldn't be able to run that time on pump gas with 550s. Running the same afr with the pump gas as race gas will no doubt lead to detonation issues unless you have an incredibly efficient motor (me thinks Buschur's bad bish). Most people will correct that by flooding the mixture (far from ideal) but works great because fuel does a great job of pulling heat out of the air. Because of that you obviously will need more injector.

That being said, when I went from 93 to 110 leaded fuel, I went from 11.3:1 afr to 12.5:1 and my injector duty cycles went from 96% to 86%.