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I've been told that these injectors are rated at 550cc and will fit an rb25det.

Is this true?

Cos i can get them real cheap.(but i dont want them if you guys reckon there crap)

What sort of power will 550cc injectors max out at with a good fuel rail and regulator?

If not what sort of injectors are the go.I'm after about 250kw to 265kw at the wheels out of my rb25det.

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https://www.sau.com.au/forums/topic/40737-13b-mazda-rx7-injectors/
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You will struggle to fit RX7 injectors into an RB25, unless you were very good in kindergarden at fitting square blocks into circle cutouts.

I dont think there is a cheap option for injector upgrades on RB25s other then change the fuel rail, or get some 550cc aftermarket one...for an R33 or R34?

for rb25 you just need a top feed fuel rail, top feed injectors and suitable collars to fit into the head. Mate has done it on an SR20 and is in the process of doing it for my RB25 head.

I would be interested in hearing what sort of power figure 550cc's will max out at. Is 500rwhp out of the question ?

The problem with rx7 injectors is there spray pattern (or lack of it). The rotors use a squirt like fuel delivery as opposed to piston cars which require an atomised mist to mix with the O2 properally. We all know how important air/fuel mixture is in a turbo motor and thats why a few tuners up here in brissy will refuse to a tune a piston car with rotor injectors.

hmm being nippon denson, pintle head cap design and identical to a stock rb20 fuel injector how does the spray pattern vary? would it be the duration that they are held open etc. Thats the only thing i can think of for a fuel injector to spray differently if they have the same design.

Unsure about R32's, but an R33 uses side feeds. Therefore 13B-REW (series 6 primaries and 20B's) will fit - apperantly. I've tracked down a couple for my RB30DET, just haven't taken delivery yet so i can't confirm. Here is a page with relevent info. Pretty sure S15 SR20's use the same style injector as an R33. http://www.nissansilvia.co.nz/tech/howtous...0Binjectors.htm

I'm using a sub-zero fuel rail ....

will the 13b injectors do the job for 280kw at the wheels??????

Is that in a rb25det with stock pistons? just that many people upgraded fuel regs with rb25dets got nice ar ratios but alot of them blew the stock pistons, and theres talk of spray pattern being the cause?

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