Today a local tuner had a 12-12 drive in dyno day. Our group had 2 NA z's, 4 NA g coupes, and 2 NA sedans ( mine and the wife's ).

The two z's were both 03's, one 5AT and the other 6MT. The 5AT had crawford hiflow cats, underdrive pullys, and something else I can't remember. The 6MT had stillen test pipes, and a JWT popcharger w/heatshield.

The four coupes were an 03 6MT, 03 5AT, and 04 6MT, and an 05 5AT. The 03 6MT had at least an exhaust, plenum, and other goodies; can't remember the specifics. The other 03, the 5AT, had a stillen intake and a borla exhaust(can't remember if it was a true dual). The 04 had a ztube, grounding kit, and fuji exhaust. The 05 was bone stock.

My 05 has the 350z middy and ztube. The wife's 04 5AT is bone stock.

So, the 03 5AT z pulled the most with a 245/228 run. The 03 6MT z was right behind him with a 243/230.

The top NA g of the day was the 03 6MT coupe, pulling a 243 even(didn't find out the torque). I was right behind him with a 241.9/210.3. The 03 5AT hit 233(can't remember the torque). The 04 6MT hit 229/??? torque. The 05 5AT put down 226/213. And the wife's sedan put down a 215/208.

So, I don't know if anybody really cares, but these numbers are interesting. Other than the 03 6MT with a bunch of stuff, my 05 6MT pulled the most, though had pretty crappy torque. I guess the changes up from 03/04 to 05 weren't completely synthetic afterall. My 6MT pulled harder than an 04 6MT coupe with fuji exhaust and ztube, and <2hp less than an 03 6MT with a bunch of goodies. However, I was just 2 ft lb's of torque better than my wife's 04 auto...

The other interesting thing to note was the performance of the z's. My hp numbers were right up there, but the 03 6MT bested my torque by right at 20 fl lbs. Where's that torque coming from? I thought the test pipes, if anything, caused a loss of torque.

At the end of the night, roughly 10hrs after his first run, the 03 6MT z ran again. This time he put down a 251/238, a gain of 8hp and 8ft lbs; we're guessing it was due to the temp drop.

Oh, and the most interesting thing I got out of my dyno runs? Although the 05 6MT's redline at 7000, my car peaked at 6500 on the dot, and dropped precipitously. At 6500, I was at 241.87. At 6600, I as at 194.76. Quite a drop. At both my visits to the track I shifted at 7000. Not anymore

Conditions:
94.23 degrees, 45% humidity.

Sorry that I don't have the graph attached; our scanner is on the fritz right now. I'll get the scan up as soon as I can.

 

Your torque was affected by the A/T's shift point recovery. In tha M/T you have the ability to keep the "R"s up between gears and not suffer the lag. Another good point
you made (meant or not) is the importance of several runs being made at different times of the day.....8 hp is a HUGE frigg'n difference......a difference of 'day and night' if you will...(sorry, I couldn't resist) This can have a bad reflection on what performance mods you've done unless you're willing to spend a whole day at it getting various runs done @ different temps and humidity. Also, it's next to impossible to get a 'constant', with any fair degree of accuracy, done on a AWD X with most conventional dynos. Thanks for taking the time to post the results. Thanks T. jbx

 

I've seen that same thing happen with dyno results. A 2005 350Z gets about 230 something, then sits for a few hours, and gets high 240s after cooling off.

You can try to correct for this by running the cars at the same coolant temp, but most dyno operators don't do this. The other thing to consider, is that the lubricant for the rollers may become less viscous after a full day of dynoing.

Otherwise the numbers you posted seemed in line with what I would expect with SAE dynojet numbers.

Also, AT cars make the most in 3rd gear. It's not just a mechanical advantage, because 1st gear makes less than 2nd, which makes less than 3rd, which makes more than 4th. MT cars make about the same 4th vs 5th, usually a 2-3 HP difference.

 

Actually, the wife's car is the 5AT, mine is the 6MT, and I still only dyno'd at 210 torque.

It was hot as hell in the garage, but still a lot of fun. We were there for almost 6 hours, and when we left, at 1AM, it was still +90 inside the garage.

 

I forgot to mention that this was a dynojet. I can't remember which gear they were using.

And it would make sense about the lubricant. The last run we were present for was that z with the 8/8 increase. There were at least 14 cars(3 pulls each) between that guys 1st set of pulls and his second set of pulls. The dyno started this aweful squealing noise as the operator slowed his car to a stop on each of pulls that last time.

You know what I think is funny? A few of the guys were pissed because apparently this dyno showed lower numbers than other dyno's they had performed elsewhere...

 

That's why I've said about 50 times on the forums that the absolute number is not the end all of discussions. There are too many factors that will affect the numbers. What you want, is to see how your car compared to others on that day on that dyno.

People like to post their number, like 250s for a stock G35, and wonder if they have a factory freak. The answer is, that it depends. Do other stock G35s get 250s on that machine, or do they get 230s.

I could say that my latest dyno was 271 WHP (2003 AT coupe). It means nothing though. But if I told you that it's a dynapack, and stock 350z 6MTs get 255-260s on it, and a stock 2005 G35 6MT got just under 270 that same day, then you have an idea of how my car is doing.

 

^^^^^
Yeah, I've read these forums enough to understand the uselessness of individual, independent dyno figures; except, of course, for a baseline/point of reference.

That is one reason was so excited to go; we ended up having 2 NA z's, 2 NA g sedans, and 4 NA g coupes. We also had an APT ST g coupe, but he's having boost and mixture problems, if I recall. That's why I didn't post his numbers.

By having all those guys dyno on the same day, we could get a much better guess at how each owner's car compared. Granted, each run was at different times; i.e., different conditions, and everybody has different mods, but it's still more relevant than a bunch of independent, unrelated dynos.

 

Just keep in mind that you don't necessarily shift at peak HP. Shift points can vary a lot thanks to gearing and often times they'll change thanks to the particular gear you're in. It's not uncommon to shift 500-600rpms after peak power in gears 1 and 2. On my old Maxima that made peak power at 6300rpms, the calculated shift points were as follows:

1-2 7200rpms
2-3 6900rpms
3-4 6800rpms

I think there was something wrong with rpm pickup on your car because loosing 45whp in 100rpm is not normal. The only time cars loose power that quickly is when they've hit a rev limiter. By looking at other "hi-rev" 298-300hp VQ dynos, I can tell that the ideal shift points should be around:

1-2 7000rpms
2-3 7000rpms
3-4 6800rpms

If your were to shift at 6500rpms in the 1/4 mile, you'd be a bit slower. I'd say in the neighborhood of .2-.3 an 2mph slower.

 

The place I'm gonna have mine done is some distance from me, but they are the 'Cat's ***' when it comes to talent....Check em' out (go through the whole site)....I love the Mustang they did for Tom Cruise and "War of the Worlds" http://www.idaautomotive.com/. Their facility is one of the best for having a controlled atmosphere and being able to do an AWD X. BCool ,jbx

 

I think the point to be mentioned is that Trey had a good time at "dyno day"!

I love dynos and can feel his enthusiasm! Track and dyno are much more my ideal, even though I have rolled my car to shows looking sparkling clean!

Trey, at 2700 ft altitude I ran ¼ mile 15.000, at about 150 alt I ran 1/8 in 9.232 (fully loaded w/normal road conditions)…

Closer to sea level I dynode on dynopack at 271hp, 249+tq

I have a somewhat unassuming sedan…

Without FI it’s a slow battle – but its fun to surprise people!

 

Trey, this was great information. Thanks for posting it.

You numbers were nearly spot-on what you'd expect using the 20-percent-this-is-bloody-inaccurate-but-it's-the-best-we've-got-without-testing-driveline-loss rule. Your numbers were 242 whp and 210 wtq; the theoretical numbers for a stock '05 6MT work out to 238 whp and 208 wtq. Pretty close considering your very minor mods.

I'm very impressed by your wheel horsepower, particularly as it's not in a vacuum. The two 350Zs tested with your car put out quite a bit more torque but about the same horsepower. Considering how they were modded, I'd have figured their horsepower numbers to be quite a bit higher than yours.

Even though the '05 G35 6MT doesn't seem to run any faster to 60 or through the quarter-mile compared with the '04 and '03 models, your dyno results indicate the horsepower bump is very real. Good to know, even if it's kinda useless in day-to-day driving. I had kinda written off the 298 number as a marketing ploy and nothing more. At least I know I got what I paid for now if I look to your one little insignificant dyno-day for proof.

 

Thanks for the response. I would like to know where my torque's going, though. Other than the wife's 04 5AT, I dyno'd less than anybody else in the torque department. At this point, that's the area on which I'd like to concentrate most when modding.

As for 1/4 times, the broad numbers generally indicate exactly what you said; no real difference. However, from *very limited* personal experience, I've been better than the other g's in our group by .3 or more. Not consistently by any means; just when comparing best-runs against others' best runs. Which is not scientific in the least, I understand.

 

Could you explain *why* I would want to shift so late after peak? Is that so when I make it to the next gear, I'm already in the sweet spot?

As for the sudden drop-off, I'm curious about that. None of the other g's/z's there had such attributes. Out of the 8 NA vq's there, I was the only one with a redline > 6600. They asked me before my pulls what my redline was, and I said 7000. After thinking about it, I distinctly remember hearing them bounce off the rev-limiter in each car, *except* for mine. Might try to get them to do it again, or go to another dyno(I know; can't compare the numbers, but I can at least compare the curves).

 

What is the mileage on your 2005? Yes they should have brought it to 7200 rpm. What gear was it done in since this is extremely important and should have verified the 1:1 gear beforehand? Are you planning on modding the 2005 anymore? If so will you be dynoing again at the same place? Will they keep your data on file so you can do an overlay between this dyno and future? How flat was your tq curve compared to others?

 

Right now I've got right at 6500 miles on the 05. As for the gearing, I can't answer. I can't remember if it was 3rd or 4th, but I seem to remember fourth.

Yes, I do plan to continue with some mods, but I don't know yet. I've mentioned that I'd like to tune the exhaust; I'm thinking about going with the hks hi-power muffler. That mod would be purely for sound, not performance.

I'm not sure if I'm gonna go back to the same place. I might try a few more dynos in my area, just to see if I can get better information(not absolute numbers). After reading evetyone's responses, I'm starting to question how they performed my individual dyno.

I'm sure they can save the data, but I'm also pretty sure they didn't save the data from Saturday, considering it was an open drive-in day.

The torque was pretty much level all the way till the end, with very little variance. So pretty much flat. When I get the scanner runner, I'll get it online. Also, the guys there said that I was running pretty rich in the upper rms. When asked how much of a gain I would see if it were corrected, they responded in the 6 to 8hp range. So not much.