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no it didnt

sorry, was 208, just checked dyno sheet.

50 psi base pressure, + 15psi boost = 65psi .. should give it abit more fuel..?

in saying that, i should be able to work out where im at with the below. theres also an article done by autospeed regarding flow rates vs pressure, basically showing that pressure increases = quite small increases in flow.. so what are stock injectors good roughly? i need to find a maximum safe setting for base pressure. http://autospeed.co.nz/cms/title_Boosting-...86/article.html

stole this from another forum:

The flow is supposed to increase according to the following formula.

F2=F1 x SQRT (P2/P1)

So, assume you have 270cc/min injectors at 36 psi pressure difference, then, if you increase fuel pressure to 42 psi, the resulting flow will be:

F2=270 x SQRT (42/36) = 292cc/min

This formula will work with pressure difference, have in mind that there is always some pressure present at the intake manifold, and it needs to be substracted from the fuel rail pressure in order to obtain the pressure difference.

Like Mcquirk said, doubling fuel pressure will lead to 1.4 times the flow, for 270cc injectors, that is some 380cc/min. BUT, the problem now will be the fuel pump, which likely won't give you the necessary flow at such a high pressure, so, it's much better to install larger injectors and work them near their test pressure.

Edited by tarmac

Dont wind it up too high, the walbros loose heaps of flow when the pressure is wound up, they only flow 500hp worth of fuel at about 40 psi, give it 70 psi, and they flow about 350hp. TBH kkr turbos dont have a great rap in regards to power vs boost needed vs lag

Dont wind it up too high, the walbros loose heaps of flow when the pressure is wound up, they only flow 500hp worth of fuel at about 40 psi, give it 70 psi, and they flow about 350hp. TBH kkr turbos dont have a great rap in regards to power vs boost needed vs lag

yeah i realise theyre shit turbos but i got it cheap. ill get the internal as tight as possible and with electronic boost control can only do me best to avoid lag / boost threshold, otherwise no worries just to drive around it.

KKR430, around i think 230rwkw is about the most anyone has made.

on the hub dyno it'll be higher, probably 240-250 (same as your 208 with factory turbo)

Plenty of results in the RB25 dyno sticky thread.

Sounds like a happy dyno that turbo will not make that power at 14psi

ive done the same turbo on another dynapack that time by st hitec in auckland with a engine thatd done 230k's, did 242rwkw, power fc, larger injectors. this tune was done by glenn suckling who has the 1600hp gtr running 7's.. even if it is abit 'happy' it gives an indication of what they can do. they are cars in the 260kw range with these turbos. an 2 degrees timing was the difference between 233rwkw and 256rwkw. a/f's are hovering around 12 .

moral of story;

kkr430 / dsr430 turbos while not the best with their shitty internal wastegates that you need to load alot of preload on and the fact the interal barely opens, are decent turbos on 25's and you can get away with standard injectors with a fuel reg.

Edited by tarmac

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