Injector Size For 300kw?

[lookingforboost]

hey guys just wondering i was thinking of using 6 S15 480cc injectors but not sure where there power limit will be can anyone shed some light for me i dont know much about injector calculating, and i have been told running massive injectors is bad for fuel comsuption etc

Power looking at 250+ hoping for 280 not sure what it will make just dont want to run out of fuel

Thanks

[TiTAN]

they should get you there, if you are worried, go for the nismo 555cc or 740cc options. tuned right these wont have any fuel econ problems.

[WARLORD]

they should get you there, if you are worried, go for the nismo 555cc or 740cc options. tuned right these wont have any fuel econ problems.

+1

[Moodles2]

You can generally get 280kw with GTR injectors (6x 444cc) without sweating (without using an FPR), so I don't see any problem getting 300kw from those 480cc injectors, there is always the option of a FPR down the track to squeeze the extra 15-20w out of those S15 injectors (but generally not recommended as the extra pressure affects the spray pattern)

[t_revz]

i went from stock to 740cc nismo and no fuel econ differences...45% duty cycle at 350rwhp

[Adriano]

I thought s15 injectors were really only 440cc, except in an s15, as they run higher rail pressures? What ecu are you using?

[.WILKO.]

Running 510cc at 290rwkw at about 45% duty cycle, no need to go bigger for 300rwkw

[Adriano]

Really, that doesnt sound right, as 440's max out around that

[lookingforboost]

great i would have gone the other injectors nismo etc but i can get the S15 ones super cheap so i was just going to get them cleaned and tested anywhere you guys recommend getting them serviced?

[ARTZ]

great i would have gone the other injectors nismo etc but i can get the S15 ones super cheap so i was just going to get them cleaned and tested anywhere you guys recommend getting them serviced?

yeah i want a set too..

[R31Nismoid]

Really, that doesnt sound right, as 440's max out around that

Agreed.

[JonnoHR31]

Running 510cc at 290rwkw at about 45% duty cycle, no need to go bigger for 300rwkw

are you injecting petrol or hydrogen.

i'm running double that duty with bigger injectors at a lower power level

[joeyjoejoejuniorshabadoo]

s15 injectors will get you to 300rwkw on pulp

my 555's max out on e85 (92%) @ 325rwkw

on pulp they are fine

[geraus]

my 740cc highflow goes up to 67% so dude you'l be fine.

[Dose Pipe Sutututu]

I thought s15 injectors were really only 440cc, except in an s15, as they run higher rail pressures? What ecu are you using?

They're actually 450cc at standard fuel pressure, 480cc is rated at a different fuel pressure as stated on that graph, cbf finding it.

[.WILKO.]

Agreed.

disagree

[R31Nismoid]

Well of course you do - it's your car. However factually what you have posted is simply not possible with just 510cc injectors. Something is up.

You are either leaving something out:

Happy dyno or higher than factory fuel pressure configuration. Which one is it?

This is usually around 85% duty (give or take) in the factory fuel pressure.

510cc = 510hp

380kw = 310rwkw (or so)... at 85% duty.

360rwkw @ 100% duty

Given as a number of people have stated 440cc injectors max out ~300-310rwkw

440cc = 440hp.

330kw or 260rwkw @ 85%

300rwkw @ 100% which is exactly the max point for standard fuel pressures as already stated (surprise!)

Disagree all you want, 510cc injectors simply cannot be flowing 400hp @ 45% duty. They can only supply 510hp @ 85%

There is more than enough information/results/posts in the pages of this forum, and all across various injector suppliers to back this up, including the 3 people that already so far disagree and no doubt there will be more if this thread keeps going.

EG: If you would make your claim with 510's @ 45% duty, that would mean not one RB26 owner would ever have needed to upgrade factory injectors for 300-320rwkw.

Fact is every single RB26 owner has had to do so... Proof is in the pudding.

(given your claim would mean 440c injectors flowing 320rwkw without being maxed out, an impossibility @ factory pressures).

[Angus Smart]

i have some new sard 800's for sale for gtr at the moment..

looking at going 1600cc or so with e85 so these wont cut it..

[ARTZ]

Injector calculator, i have no idea how accurate it is...

http://www.gtsparkplugs.com/InjectorSizeCalc.html

[gwilkinson34]

It's fairly simple. Don't get the size that's just big enough for your power level, because once you are there, you'll want more. Guaranteed.

Go at least 740cc so you can run 50/50 ethanol or E85 (if it ever gets consistent out of the bowser).

If you tune it right there's no harm in running bigger injectors, very little cost difference, and way more headroom for more power down the track.

Do it once, do it right.