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  • 1 month later...
Definatly do cam gears, on stock cams if need be

Injectors are easy; What HP at the motor do you want?

I would be very dissapointed if it did't make over 500bhp at the fly, 600 would be better. just no lag, 2k spool up would be good.

Im thinking about 800cc SARD injectors.

Is it just something about RB's that require massive injectors? Not having a stab at anyone, just posing the question...

My old man runs a TT 1UZFE, it makes 480rwhp @ 9psi and uses 340cc injectors at I think 70% or so duty cycle

So many people told me to go 550cc or bigger when building my RB25 and aiming for around 500hp at the fly (makes around 380 @ 18psi through built auto + 4200 stall)

Something to do with boost or engine design or something?

1UZ = 8 cyl so 8 cyls make 480hp, or 60 hp each.

RB = 6 cyl, so 6 cyls make 480hp or 80 hp each

rule of thumb, 6cc of fuel per hp.

so for the v8 480/8 x 6 = 360cc/min per cyl

for the 6 480/6 x 6 = 480cc/min per cyl

360 x 8 = 2880

480 x 6 = 2880

so both engines (if they are making the same power) require the same amount of fuel per minute, just the 1UZ spreads that over 8 injectors not 6.

does that answer ur question cactus?

edit: and as said above, a good tune can get rid of any low rpm drivability problems that might arise from oversize injectors, plus you have room to move in the future.

Edited by Kranker
1UZ = 8 cyl so 8 cyls make 480hp, or 60 hp each.

RB = 6 cyl, so 6 cyls make 480hp or 80 hp each

rule of thumb, 6cc of fuel per hp.

so for the v8 480/8 x 6 = 360cc/min per cyl

for the 6 480/6 x 6 = 480cc/min per cyl

360 x 8 = 2880

480 x 6 = 2880

so both engines (if they are making the same power) require the same amount of fuel per minute, just the 1UZ spreads that over 8 injectors not 6.

does that answer ur question cactus?

edit: and as said above, a good tune can get rid of any low rpm drivability problems that might arise from oversize injectors, plus you have room to move in the future.

Yeah that definitely makes a lot of sense, it kind of makes previous posts look about injector requirements excessive. to achieve say 480hp at the flywheel, which I assume is the correct measure when looking at the assumption 6cc fuel per hp, then 'theoretically' 550cc comfortably deliver the fuel requirements to make that 480hp. 1000cc as suggested is a little overkill...

I was more just wondering why so many people suggest massive size injectors for an engine that is not really making HUGE power :P

But thank you for the response!

R

lol richi buggered off, you shut him down den, btw get some pics up when you finish this monster of yours, mayby the guy who built if forgot to put the keyway in, and when they replaced the ballancer they put a keyway in and didnt tell him lol

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