I installed NISMO Cams, Headers, CAI and Cat Back Exhaust on my 2004 6MT Z over the last year. Three months ago I dyno'ed at DynoComp of Scottsdale. The first two pulls produced 230 rwhp in 4th gear and the third produced 236 rwhp in 5th gear. Allowing for 25% to 28% drive train loss on this dyno I was at 295/300 crank horsepower. I was disappointed. The A/F ratio showed the car was running rich which was suprising given the mods (I thought).

I shared this with Tony (Motordyne) before I bought my spacer and he recommended driving the car very hard before dyno'ing again and cooling the engine with A/C on before the next dyno run (with A/C now off). The car (with 5/16" spacer installed and NO other mods) just ran 262 rwhp with the same 91 Octane. Richard (from Dynocomp) asked if I had modded the car in any other way. I have not.

These results show a crank horsepower (on this dyno) of about 330 HP, and that is only up to 6600 rpm. The NISMO Cams (already installled)and Technosquare re-flash (coming soon) may push the rwhp much higher at 7100 rpm.

We installed Megan test pipes immediately after the 262 rwhp run and dyno'ed the same max horsepower again, but with wildly fluctuating incremental horspower measurements and a seriously dangerously lean A/F ratio.

Tadashi (Technosquare) suggested that there was more power to be had with the Test Pipes if we re-mapped the ECU to provide more fuel to the engine. I drove the car home and back to work the next day and decided to dump the test pipes. The noise is horrific and the raspiness unbearable (IMO).

The O2 sensor was screwed up (nobody's fault, it was coroded) and that cost me $175 to replace when I re-installed the stock Cats. On that subject, if anyone wants the Test Pipes they can have them for $50 plus shipping including the jammed O2 sensor...)

I doubt that the Motordyne spacer gave me all of the 26 extra rwhp. I think that the ECU was in limp mode the first time I dyno'ed, but clearly the spacer is an awesome, awesome, mod. I also think that my results throw some doubt on the concern about using the spacer with a long CAI induction such as NISMO, but I plan to test again with a stock air box/pop charger.

As far as Test pipes are concerned I highly recommend checking your A/F ratio and possibly re-flashing if you can stand the noise (I couldn't).

I will post the dyno graphs if I can figure out how to use a scanner!

I will post again after the re-flash. I plan to do the lower plenum mod that Tony is bring out first...

 

heads / cams / intake / test pipes / reflash / plenum -- should be making at least 270 whp. Probably closer to 280-285.

 

ditch the cai, go short tube

 

yes...go short ram...

Are the megans resonated? If so, I'll take em for $50. PM me with a pic of the test pipes.

 

I made 262 rwhp on the dynocomp dyno, that is equivalent to 275 on a dyno jet. Alo, I don't see the benefit of the Cams yet because I only rev to 6100. It will be interesting to see if the car will make more at 7100...

 

umm 25-28% drop i highly dought that with RWD that drivetain drop is hardly even seen in 4wd cars

1000 posts!!!!!
man why did i do it on this thread

 

that is correct...the dynocomp AWD dyno sees a 25% drop compared to closer to 18% for the dynojet...stock Z's dyno 220 to 230 rwhp on this dyno....sorry to disapppoint you...

 

This is wat I don't get. If you run the AC before the dyno u get better results from the spacers as if u didnt. So isn't that false hp/tq??? Yes on the dyno u make the extra hp/tq but how would u ever be able to reproduce that extra pw while your driving unless one turns on the AC before a race and then turn off the AC once u start the race.

 

You're missing the point...if you drive the car you have air flow...cooling the engine down reduces heat soak associated with dyno'ing a car six times in a hot workshop in Phoenix. This mimics the real world of driving the car in 5th gear at 6100 rpm, which would be 130 mph of air flow...

 

The car will clearly "make more" at 7100rpm if you add cams.

 

I already have the cams on now, but haven't re-flashed yet. Hopefully there is more power above 6600 rpm. I'm going to install Motordyne's lower plenum mod (for MREV engines, which is what I now have after the 5/16th install) and I'm going to the stock intake with JWT pop charger. I'm going to dyno one last time and then re-flash.