Denso GTR injectors are rated 550/570cc the value is arbitrary depending on the fuel pressure when tested.
The # on the side is just a production time stamp that's why it's not showing up on search engines.

 

That makes sense to me. Thanks for the good info!

 

I'm thinking of going from 285/35/18 rear tires (on the 10.5" wheels) to 295/30/18 to get a bit more rubber on the ground and just wondered if this is basically an example of a staggered setup? Fronts are staying 265/35/18.

Also got new drive and blower belts, 4 smooth idler pulleys and an automatic tensioner assembly (has a smooth idler) coming Mon. just going to get some new items in place.

 

New drive belt (7 rib), back blower belt (8 rib), auto tensioner with smooth idler, 3 smooth idlers and 45 blower drain line fitting. I'll get these changed out soon.

 

Randy, be careful with those 295/30s. You're adding 10mm of width but the 30 aspect ratio means you're taking out nearly an inch in diameter. If you have VDC, it won't like it. If you don't, the speedo error and gearing change (although lowering it will make it quicker off the line) will/can be annoying.

 

Thanks for the good info. Mic! I had read about that 295 going quite a few more revolutions per mile, but figured that I'd put this out there to see the feedback that may come back.

 

Coming along nicely Randy, one of the best high quality ongoing builds here.

 

https://conceptzperformance.com/niss...-6_p_26218.php

Got these new spark plugs today; I had talked to CZP about these and they highly recommended these iridium plugs for a boosted HR (also is an '09+ GT-R plug). They are pre-gapped at .031 and I'll be getting them installed in a few days. My tuner was here last week and we took the car out to check #'s and do a live tune; the car had been running richer than I thought since the return fuel install with the 1000cc injectors, so he leaned that out.

I've had a bit of up and down idle issue and some sputtering at lower speeds; I feel that these new plugs could be key and if they alone improve things, then they are worth every penny to me ( interested to see what the old plugs look like). He will be here in town again a month from now and we'll hit the road for some performance tweaks/tune!

Anyway, these NGK laser welded iridium plugs (one step colder) looks like an even finer/thin electrode tip than the one step colder NGK iridiums I have in the car now, hard to see clearly in the pics, but the very tips are almost needle like. I'll post up if I notice any improvements with the way the car runs after these are installed. No, these suckas are not cheap, but as you can see on the link, they were on sale and marked down quite a bit to only $100 "bargain barrel" hehe! Some pics:

 

New plugs installed today and then took the car for a good run; definitely has improved things and feels strong but I still need to get a good tune and I'll see if the tuner wants me to do some basic e-tune uprev log/s before he is here in town in a few weeks. *old plugs looked like they had seen better days!

 

BigBlue, how are you liking the new power with your 3.9 FD?

 

For a long time I had no intention to go FI and my car was a strong little NA car with the full MD true dual exhaust, ultra long dual intakes, bilsteins, sways and always a good solid tune on it; ran like a champ.

That is why I had decided to go with the 3.9 fd gears. I'd highly recommend them if you are going to stay stock/NA, but if I had any idea that I'd be sitting at 450 whp now, I'd have just left the diff. alone, stayed at 3.5 fd and save all of that $ for something else.

*got to go easy in 1st (and 2nd) with the sc setup that I now have so I'm not getting any more power from the 3.9s; thanks for asking though.

 

Whew, good thing I didn't swap yet. I have a spare pumpkin and 4.08 gears with a nismo 1.5 lsd that I was gonna do.

 

My tuner is in town and yesterday (Sat.) and today we took the car out for a variety of driving modes; on local streets, freeway and open road and he got things smoothed out. He has created 3 new maps for me, right now #1 is a good one, I'll check out the slightly leaner #2 and richer #3 maps and let him know details. During the WOT pulls the car really hammered down and feels very quick and strong.

Always nice to have the luxury of your tuner hooked up as you drive, checking and tweaking different parameters as you go; this time mostly focused on fueling issues since now I have the return fuel kit and 1000cc injectors. I'm very glad to have that tuning done for now and we had 2 beautiful 80 degree (finally) days to do it.

 

 

I got these today from Z1 motorsports, upgraded hatch struts. These are the high pressure ones, #2 of 3 options; should be just right for the wing's extra weight; plus tired of holding the hatch open with the back of my head while loading stuff in or out! I think I can probably handle this extremely technical swap out of the originals!

*Note: Got them installed and these struts are "very" strong units! Love 'em already; hatch goes us effortless, stays up solid and have to push firmly to close it! Definitely recommend these; should have got them 2 yrs. ago.

 

Really nice upgrades and congrats on keeping your 10+ yo Z in pristine shape.

 

I talked to a guy who used to work at the shop where I have had some custom work done (he had prepped/painted my hood, wing and front bumper cover); now he has his own paint/body shop, so I got it in for a professional buff/polish. He spent about 5 hrs. on my car and he fixed a couple of nicks in the paint also; in person definitely looks better. Nice to have that done; took some pics on this cloudy day:

 

I swapped my rarely used pass. side seat onto driver side rails and vice versa; like having a new driver's seat.

 

I sanded, primed, spray textured/matte black painted my charge pipe; turned out well and I think looks cleaner. Some pics:

 

Got a set of rear tires put on today (got to keep the foot off the gas!); went with the new Sumitomo HTR Z5 (285/35/18). The fronts are still in great shape, so I just had rears put on at my neighborhood Big O tires; very hard to beat these tires for the price ($142 per)!
**I recommend them with no hesitation.