Jump to content
SAU Community

Recommended Posts

I'm starting to put plans together to up the power in my R33 gtst. It has/will have a bunch or normal mods - bigger turbo, FMIC, boost controller, full exhaust, nismo fuel pump, Power FC etc.

The thing Im unsure about is that of fuel injectors. I had planned to go Nismo 555 as a step up from standard. I'm not planning to chase high power with my car, I'm just planning to make the most of my mods and get it tuned so its comfortable and reliable as my daily, but still has the power that these mods allow. That said, I'm wondering what life would be like getting the next size up injectors; 740s?

What's the difference in Nismo 555 vs 740?

For standard fitment, are they side or top feed?

and

Is a fuel pressure regulator something I would need in my modifications too, or is it unnecessary?

740cc man, 555cc you'll run out of injector very quickly.

I'm running 875cc stainless steel top feeds and at 343kW I'm already sitting at 87% duty.

Go top feed man, if you use half height injectors they will fit underneath the stock plenum easily without any silly spacers ot deleting hoses like other homo kits.

The difference is 185cc.

555 would be fine for up to 350kw ...I bought 550 Deatschwerks but today I would buy something more modern like a set of ID750s from Scotty. Get in touch with him and he will give you a good steer.

Get a more modern ECU if you can afford it too - otherwise Power FC will be fine.

For the price of nismos you can get conplete kit with everything you need to fit top feeds into r33 its what i just did 1000cc xpurts 40mm length ,rail,aeroflow reg,fittings,hose all off Scott.

Not a big fan of the 740cc side feeds, we have tuned heaps of both the 555's and the 740's and the 740cc injectors never tune up anywhere near as nice, they don't idle as well, and the cruise isn't as nice.....WOT is no different but the rest is.

If it was me and needed anything bigger than the 555's I would be doing a top feed setup with Bosch 1000's

I've tuned with the 740s before on a SR20 but not on a RB and didn't have real issues.. but taking note that per cylinder a SR uses more fuel than a RB hence idle/cruise might have been better as it required a higher duty cycle

  • 4 weeks later...

Take the majority advice dude, ditch the Power FC and go for something a little more modern(adaptronic, haltech), go with the bigger injector. I use 740cc Nismo injectors which are great. I've also used the 555cc nismo injectors. I had no issues with either car idling with my Power FC. My 740cc crack about 60% injector duty cycle so I have headroom for E85 but I will be cutting it OH SO CLOSE.

If you're gonna do it, plan it properly and do it right. I started modding my car years ago. Injectors have really come down in price and there are some more options for ECU's. The real pro's of a modern ECU are you can add inputs for mafless setups, flex fuel, other sensors etc. The pfc is a brilliant ecu but its outdated. A larger resolution can also give a tune far more detail and it can make the car feel just that much smoother.

If I was building my car today from scratch, none of the parts I have in there now would be used. They're good for their time and back then more affordable than what is available now. I also was lucky, I picked up my nismo injectors pretty damn cheap. Even cheap for todays prices. They've got up since I bought them.

With that said, I love my car :D

Edited by SargeRX8

FYI;

Nismo 555's are Side feed, and drop in to your standard rail. yes you will need a reg, anytime you change your fuel system from stock, as you will need to re-calibrate the pressure. ID1000 or EV14 injectors are top feed and require custom rail/collars.

sounds to me your pretty much doing teh same thing i did, on my first round of mods, with a very similar parts list. in which i have my old pfc and tomei z32 for sale atm, which got me up and over 500rwhp.

as for the comment about the 1000's being cheaper, not true. sure the injector itself is but its all the other shit u gotta change that adds in the price, and will ultimately cost you more. the nismos drop into the stock rail/lines etc job done. the bosche 1000's need a rail, collars, custom sleeves machined, .. then lines, and fittings and a decent return.. and u still need a reg either way.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • The rain is the best time to push to the edge of the grip limit. Water lubrication reduces the consumption of rubber without reducing the fun. I take pleasure in driving around the outside of numpties in Audis, WRXs, BRZs, etc, because they get all worried in the wet. They warm up faster than the engine oil does.
    • When they're dead cold, and in the wet, they're not very fun. RE003 are alright, they do harden very quickly and turn into literally $50 Pace tyres.
    • Yeah, I thought that Reedy's video was quite good because he compared old and new (as in, well used and quite new) AD09s, with what is generally considered to be the fast Yokohama in this category (ie, sporty road/track tyres) and a tyre that people might be able to use to extend the comparo out into the space of more expensive European tyres, being the Cup 2. No-one would ever agree that the Cup 2 is a poor tyre - many would suggest that it is close to the very top of the category. And, for them all to come out so close to each other, and for the cheaper tyre in the test to do so well against the others, in some cases being even faster, shows that (good, non-linglong) tyres are reaching a plateau in terms of how good they can get, and they're all sitting on that same plateau. Anyway, on the AD08R, AD09, RS4 that I've had on the car in recent years, I've never had a problem in the cold and wet. SA gets down to 0-10°C in winter. Not so often, but it was only 4°C when I got in the car this morning. Once the tyres are warm (ie, after about 2km), you can start to lay into them. I've never aquaplaned or suffered serious off-corner understeer or anything like that in the wet, that I would not have expected to happen with a more normal tyre. I had some RE003s, and they were shit in the dry, shit in the wet, shit everywhere. I would rate the RS4 and AD0x as being more trustworthy in the wet, once the rubber is warm. Bridgestone should be ashamed of the RE003.
    • This is why I gave the disclaimer about how I drive in the wet which I feel is pretty important. I have heard people think RS4's are horrible in the rain, but I have this feeling they must be driving (or attempting to drive) anywhere close to the grip limit. I legitimately drive at the speed limit/below speed the limit 100% of the time in the rain. More than happy to just commute along at 50kmh behind a train of cars in 5th gear etc. I do agree with you with regards to the temp and the 'quality' of the tyre Dose. Most UHP tyres aren't even up to temperature on the road anyway, even when going mad initial D canyon carving. It would be interesting to see a not-up-to-temp UHP tyre compared against a mere... normal...HP tyre at these temperatures. I don't think you're (or me in this case) is actually picking up grip with an RS4/AD09 on the road relative to something like a RE003 because the RS4/AD09 is not up to temp and the RE003 is closer to it's optimal operating window.
    • Either the bearing has been installed backwards OR the gearbox input shaft bearing is loosey goosey.   When in doubt, just put in a Samsonas in.
×
×
  • Create New...