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hi guys,
i have a quick question about the boost, i have a 1990 gtr32, she's basically in stock condition with slightly upgrade:
- the Greddy fuel rail
- new splitfire coils
- Tomei 270ltr/h fuel pump.
- new Iridium plug (heat range 7, gapped 0.8)
-Blitz intake
-koyo radiator

just wondering if anyone know how much hp (approximately) will i run if i change the stock injectors with nismo 550cc injectors and re-map the ECU??
-444cc to 550 cc is not that much of difference will it stil pretty much the same hp as the stock gtr???

thanks guys, very appreciated!!!
 

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no point just changing injectors AFAIK , as the car will need to breathe more to get the most out of them

best to up the boost at the same time (observing the limits of the stadnard turbo's)

mook
 

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to run 500 + you will need to change the turbos, at least steel head gasket and it'd be a good idea to uprate the pistons and rings. any more and you'd be wise to have a full rebuild.

550 cc injectors will support about 500 bhp and maybe a bit more if you tweak the fuel pressure. but like mook says on their own there is no point.

std injectors will support 400+ easily.

rule of thumb in a 6 pot engine is cc's of injectors is roughly equal to maximum power they will support. I.e 440cc injectors will flow enough for 440bhp, but you will be maxing them out. never a good idea long term..

hth
Steve
 

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Yep indeedy ^^^ what they said :)

550cc injectors, iridium sparkplugs, uprated steel turbos, uprated fuel pump, programmable ECU & remap are the basics for 500bhp. Many also choose to uprate the intercooler & pipework too.

If in good working order the factory AFMs SHOULD sustain 500bhp. But not much more.
 

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I think this is the first thread I have read on this forum, where everyone agrees :D
 

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injectors and a ecu remap will not give you much unless you can get the thing breathing more. All it will do will reduce the injector duty cycle due to the larger injectors.

To get any sort of real benefit from changing the injectors, you will need to either increase boost or change turbos (or both) and look at changing the dump and front pipe (if stock) to allow more gas flow and also a larger exhaust (if also stock)
 
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