What's the max bhp for 440cc injectors

Hey guys as above. As there's mixed answers in this.

I've been wondering this myself but after a chat with Noz I would say 440bhp with a tiny bit to spare. I suppose a lot of it depends on fuel pressure.

I believe at full BPU the injectors are close to running at maximum fuel duty.

If you are looking to run anything further I'd get larger injectors.

BHP as above though at 440 I'd say it close to max.

I'd say the maximum is really around the 400bhp mark tbh as you should never really run the injectors to there maximum and generally BPU on a J spec supra is around the 400bhp mark, 440bhp is more likely to occur on a UK spec supra but that has 550cc injectors and I believe a larger fuel pump

Probably worth mentioning when I'm talking about 'max' I don't necessarily mean they're safe at that level, just what they could acheive at full duty. I think 'thetrashcanman' has it pretty much summed up

If you upgrade the injectors, you should upgrade the fuel pump.

The generally accepted rule for JZ injectors is 1hp per cc, minus a bit of duty for safety, around 400hp.

80% DC is the recommended max, but you can push this further. At 90% you are running max of around 400hp. An Apexi AFC or other variants can help in managing out lean spots. My Supra was running approx 440-460bhp and the AFR's were spot on.

well this just proves my theory as im running a 1jz single. im dynoing 488.9BHP on 440cc injectors. im also running 10.0 on my aem wideband afr my mate also dynod the same day after me on 440s and dynod at 508.4 on a piping hot day and running 10s on afr again on a piping hot day.

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dynod yesterday

at 1.1 bar also

I've seen cars make a little over 440hp with these in but I wouldn't advise it. It's usually calculated at 1cc per hp. Most mappers won't push injectors past say 90% ish.

yeah but a whos says the toyota ecu will run higher then 85% duty.... in all their testing and their reliability record do you think they would over make the duty over the recommended level :\

injectors after flow cleaning will show what they flow and at what pressure iirc rc injectors state 85% duty for the flow rates

btw it was me at 508 bhp.

Let's be honest, it's pretty easy to just get a set of drop in 650cc's or alike (if J-spec) and run the boost and fuelling safely.

Let's be honest, it's pretty easy to just get a set of drop in 650cc's or alike (if J-spec) and run the boost and fuelling safely.

+1 to that its a relatively simple thing to do, I would have thought any do it yourself mechanic could do

Let's be honest, it's pretty easy to just get a set of drop in 650cc's or alike (if J-spec) and run the boost and fuelling safely.

Agreed.

well this just proves my theory as im running a 1jz single. im dynoing 488.9BHP on 440cc injectors. im also running 10.0 on my aem wideband afr my mate also dynod the same day after me on 440s and dynod at 508.4 on a piping hot day and running 10s on afr again on a piping hot day.

Unless youre running massive fuel pressure, that shouldnt be possible.

well this just proves my theory as im running a 1jz single. im dynoing 488.9BHP on 440cc injectors. im also running 10.0 on my aem wideband afr my mate also dynod the same day after me on 440s and dynod at 508.4 on a piping hot day and running 10s on afr again on a piping hot day.

 

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dynod yesterday

Out of interest Paul, who mapped the cars and what ECU do you have?

Out of interest Paul, who mapped the cars and what ECU do you have?

Supraturbotimmy street mapped it I'm using a apexi safc and a stock Ecu.

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My fuelling is as rich as it comes. So there's nothing not safe about running it

Unless youre running massive fuel pressure, that shouldnt be possible.

Nope still on standard fpr and fuel pump at mo I have a walbro to place it just not got round to yet

well this just proves my theory as im running a 1jz single. im dynoing 488.9BHP on 440cc injectors. im also running 10.0 on my aem wideband afr my mate also dynod the same day after me on 440s and dynod at 508.4 on a piping hot day and running 10s on afr again on a piping hot day.

 

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dynod yesterday

Can you post both dyno plots showing the correction values?

Don't have them I only have the power level of the WHEEL hp at 436.6 and the FLY at 488.9 don't have the graphs at min as at work till Friday

I have 6 new 550 uk spec injectors for sale

I have 6 new 550 uk spec injectors for sale

Ah right do they come with resistor I don't want them but I may no someone else

Ah right do they come with resistor I don't want them but I may no someone else

No i just have the injectors, still in their protective bags unopened from

Toyota, i was going to fit them to my car but i sold it a couple of months ago.

how much you asking mate?