I have had some problems generating the "proper" amount of power that my Stillen FI should be making. One of the things that was brought up is that the Nissan and Infiniti's have something in their ECU that prevents full engine performance before the car is truly broken in at 3000 miles.

I put the Stillen stage 2 on at 1750 miles (I was under the impression that the car was broken in) and thought I had pretty good results. I have been able the take other SC's off the line and am enjoying the car. I did not dyno the car until recently, what that gave me was:

baseline: 235 hp 228 tq
Stage 2: 290 hp 257 tq

my AF ratio started at 11 and rose to about 12 over the run.

The TQ curve is perfectly flat (only good part).

It is a completely stock ZR with only a K&N drop in. I spoke to stillen and they agree it is unacceptable, especially the TQ. I have a conference call with one of their techs this afternoon.

The only thing they brought up was that the nissan's have something in the computer that will not let the car run too hard before it hits 3k miles (I have 1950 - I just didn't drive the car that often in the winter).

I would like to hear any opinions. I think the install went well, but there is no way to tell what kind of boost I'm getting (no gauge).

Thanks,
Adam

 

Does not sound like a possibility. Other owners on the board have done their installs just off the showroom floor with no problems. Sounds like it is running a little lean too...should be closer to 11 in the higher rpm's. What kind of dyno???

 

Yes the A/F maybe hurting him . You would get better hp if you started at 12 to 1 and got down to 11.5 in the upper rpm range

 

I don't know what the problem is, but I don't think it's the AF. At 5500 my AF was 11.5 - It didn't really go up to 12 until 5700-6500.

I am pretty skeptical on the 3000 mile thing.

I think it was a dynojet but am no 100%. I will try to scan and post.

 

Looks like she is running out of fuel at the top.

 

I spoke to a tech at stillen who then ran it by their R&D manager. The R&D manager took a quick peek at the dyno. He immediately asked about the boost level. He thought it was a little rich too, and said that usually he sees that when the car is down on boost.

They explained that for some reason (he wouldn't get into it) Z's with different manufacturing dates need different size pulleys to make the same amount of boost. Unfortunately I do not have a boost gauge, but I will be stopping by AAM on monday (hopefully) to put a boost gauge on and see what the result is. I really hope it can all be solved by just switching to a smaller pulley.

I guess my advice to anyone going FI, no matter which system, is to have a boost gauge installed. Even if you are doing something like the stillen or vortech (which don't really require any tuning).