Chuck can I ask what you mean by undersized injectors? Are you talking about for trying to make 500+whp? I'm asking because we didn't need larger injector for the tune on my car.

What are your idcs? They use smallish injectors. Running a too small injector at a high idc is not as good as running the next size up injector at a more reasonable idc.

yeah a local guy I know has the Stillen kit and they were running 95%+ IDC's on the injectors that came with the kit during the tuning process so they couldn't maximize power.

He had to 'upgrade' to 600CC injectors, which is absurd since the stockers are ~400CC.. how tiny of an injector did Stillen include??? lol

My kit came with 600cc injectors.

Did you buy the kit new or upgrade it in any way? It didn't use to be 600cc.

Yeah the local guy I speak of got his right at a year ago I believe and it came with the 540's or whatever.

They may have bumped to 600's since then.

Also, if you got a "tuner" kit and then had your installer/tuner get the injectors and pump, that would explain why you have 600's as well.

If you get a custom tune instead of using the stillen tune doesn't that void your warrant?

Yep it does.

Chuck... the kit comes with 600cc injectors.

Did it always? Quite a few people had really high idcs on their injectors. Hopefully the improved that part of the kit.

IDK about that.
I have a new kit on my car and it came with 600cc injectors.
BTW, I do not experience any of the problems that are constantly mentioned here.
The kit max out at around 460 RWHP, which incidentally it's not very far of what the stock motor can take safely.
The kit as it comes makes 409 RWHP, but the fuel tables shows a very rich condition, then when it's properly tuned goes to 440 RWHP, on a bone stock car (factory exhaust included), not bad at all for a sleeper.
Realistically our motors are safe up to 500 RWHP with a good longevity ahead.
If we like to push the envelope further, then a short block is in order, a TT set up, big intercooler,etc,etc, and 700/800 RWHP is attainable, but I don't think the tranny can take it.
Back in 1992 when I had my second 300ZXTT, I max out the package with stock internals and the car makes over 500 RWHP at 2 bar, it runs very reliable with no breakdowns,but the tranny did not like 473 RWTQ, so powershifting was a big nono.
However I'm always have a lot of fun with the Z cars.:ughdance:

Very nice HP. Is your car manual or auto. I have installed Stillen now headers and cats. Should I return stock headers? The cat's material inside tends to break apart. The question is whether to clean the interals of the stillen cats out and leave them as test pipes or to return stock cats.

thanks :)
Bart

Yeah but the gtm stage 1.5 or 2 kit makes 50hp more than that, and the vhr should take closer to 550 s/c or more safely because the torque comes on more even. As for the tranny you cant compare the 6 speed to the old z32 5 speed. The gearset in our trans is huge like 50% bigger than a mkiv supra tt tranny huge. There is a reason the thing weighs as much as it does. I've only heard of two non synchro related failures on the new 6 speed and both were near or over 700whp, and I know there are cars running even more than that.

Edit: Also both failures were input shafts breaking off near the pilot bushing so the could have been related to the clutch.

What kind of dyno are those numbers from? For an unmodified kit, that's pretty high. What does a stock 370 put down on that dyno?

Sorry to hijack😏 but should I remove stillen headers and return stock headers? Also the stillen cat's material inside tends to break apart. The question is whether to clean the interals of the stillen cats out and leave them as test pipes or to return stock cats. Stock headers and stillen cats? Stillen headers and stock cats? Stock and stock or stillen and stillen?

thanks :)
Bart