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Sydneykid, have you ever tested a 370cc injector at 58psi?

Also, I realise that bosch pumps are rated at 75psi, but would mounting the pump inline after a surge tank have any bearing on the max flow potential, also have you ever tested a bosch pump to see if it flows what it is rated at?

I wouldnt put it past bosch to rate pumps on the lean side, as if someone took there figures and then the pump didnt match they would probably have good grounds for a legal suit.

might be interesting if the increase flow on injectors varied exponentially instead of linearly as pressure increased. this wouldnt be so evident at smaller increases in fuel pressure - might go further to explaining the seemingly impossible.

Just guessing, but there must be a reasonable explanation for this, and I think its a bit of a cop out to just say the dyno is reading high.

Steve, I don't mind them thinking the dyno reads high, I know better, and at Perth Autosalon I'm sure it will read higher than SST's dyno. Either way, as I said before, it's not the power which is the interesting factor, it's that fact that it's stock internals, stock injectors and stock cams:D

That is fair enough; in that case did you drive your car on the street at that power level (if yes did it feel like a 120+ mph car) or did you get that reading as a one of on the dyno to see what could be had...?

What sort of power did you have on the 13.5@104mph run and was it on the same dyno...?

GTST V spec, nice figures. The most i could make on stock injectors was 387rwhp. By going to 660cc injectors my power increased to 421rwhp. I know a car with same set up as you making 402rwhp on 12psi. But the key is, "GAS". Im sorry but i dont think you made those figures with out nitrous. If you did then f**k me!!

When you do let us know. :D

The only thing that comes across as impossible is achieving that power with the stock injectors, especially at %80 duty cycle. Maybe you are running more pressure than you know through the fuel reg.

The bottomline is that your setup at that power level could not be considered as conservative and safe and even though it is achievable, it's advisable to upgrade the injectors and internals. I am linking your thread with the US mentality of running 9's with a stock bottom end in a Supra.:D

Emre, I plan on doing internals, and I'm only using this power for a dyno shootout until I get them in, on the road it's a more convervative 360rwhp:D Maybe the fuel reg is reading wrong, I can put another meter on to check though.

RNS11Z, NOS is for loosers, and I sure as hell don't have it, I can send you a pic of my engine bay if you want to look for the NOS lines:bahaha:

Hi guys, the Bosch fuel pump data follows;

Bosch 910 pump is 200 litres per hour and supports 450 bhp at 73.5 PSI

Bosch 975 pump is 228 litres per hour and supports 500 bhp at 73.5 PSI

Bosch 984 pump is 228 litres per hour and supports 500 bhp at 73.5 PSI

Bosch 044 pump is 330 litres per hour and supports 730 bhp at 73.5 PSI

Bosch 040 pump is 235 litres per hour and supports 520 bhp at 73.5 PSI

Sorry maybe I need to restate something I posted earlier, it was late, I was tired etc.

Increasing the flow potential of the fuel pump does not increase the flow of the injectors. The only thing that increases the flow of the injectors is increasing the fuel pressure at the injector ie; in the fuel rail.

There is one exception, that is when the flow rate of the injectors is greater than the flow rate of the pump. I have also seen one case where the fuel pressure regulator was too small to return the excess fuel to the tank.

Hi Steve you asked, "have you ever tested a 370cc injector at 58psi?"

That's a bit tricky, the Bosch pumps are rated to 73.5 psi, so that would only leave 15.5 psi (1.05 bar) for boost. I have found that "overdriving" an injector past 110% of its rated pressure (and therefore flow) makes the results unreliable/inconsistent. The solenoids and springs have trouble closing the injector against more than that sort of pressure. Plus it puts huge strain on the standard pipes, hoses and clamps. So I simply don't do it.

As for the flow rating, I have only tesed an 044 and it flowed 2.75 litres in 30 seconds, which was exactly its 330 lph rating.

Hope that helps

  Quote
Originally posted by GTS-t VSPEC

I did the 13.5@104 with about 260rwhp.

I've done 118mph with the 360rwhp I use on the street, and that's with bald tyres, so I'm confident I'll get a decent mph:D

hahaha big difference between doing a 118mph and getting the power down to get a decent enough 60ft time to be able to do 118mph,

When are the next drags on as it will prove what you've got once and for all, time slips don't lie :D

sydneykid, could you explain what you said about an RB25 being 90% efficient, and an F1 being 97.2% efficient? from where are these values taken? I guessing not from the chemical energy of petrol to flywheel power. From the little amount of mechanical eng. that i studied i was under the impression a petrol car, overall, was about 30% efficient

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