datspeed77

iTrader: (1)

Speed Alliance will be at the Extreme Autofest Super Show on Oct.5th at the Coors Amplitheater in San Diego. Hope to see some of the local guys out there. We will have about eight of our cars out there including my 350z. I need witnesses that I'm not squeezing. Here's the dyno sheet!

mcduck

dat... don't take this personal... Just training to analyze the facts based on what we know..

As shown by numerous results on this site, the CAI is good for maybe5 5-6hp and the Pulleys good for another 3-4. So between those two mods, we're talking about a 10hp gain, but I'll be gracious and say 12hp.

We will assume your Z is at the top of the gene pool and use a high stock hp number. Highest I've seen on a bone stock Z was 246rwhp. So, stock car with CAI and pulleys would be 258.

Mustang dyno produced 310 on your Z... a difference of 52rwhp... for your custom Y-pipe and Apex R&D exhaust??? Umm... No....

I said it before and I'll say it again... NO exhaust is going to land this motor a gain of 50+rwhp. Maybe if you do some serious internal mods, but not on the stock motor.

Another thought... Are you running cats? If you have test pipes, that could account for some of the difference. Also, does the R&D exhaust include headers or is it just a cat-back exhaust. Again, headers could account for some difference as well. If your mods include special Apex R&D headers, no cats (test pipes), the special Y-Pipe, AND special R&D dual exhaust, then I'd be more inclined to accept the numbers the Mustang dyno recorded for you (assuming that it is reading 10-15hp high)

base ... 246
pulleys ... 5 (gracious)
CAI...6 (again, gracious)
headers... 8
test pipes... 10
secret Apex R&D exhaust & Y-pipe = 20
Total = 295

Add in fact dyno is likely off 10-15 hp and you have 310. In this case, the number would make sense.

Otherwise, if you seriously have no other mods on your car, I have to join the others on this board who say that dyno is waaaaaay off.

Apexi350z

iTrader: (3)

the thing is, he doesn't even have NISMO cams?!?! so where's all the hp coming from?

mcduck

The NISMO cams are supposedly good for about 15rwhp. This is approximately the same amount that headers and test pipes will give. Now, if he's not sporting headers and test pipes as part of the R&D exhaust, something is fishy on the car and the dyno.

Also, we are assuming he was at the higher end of power output with his stock car... forum members have seen dynos ranging from 225-245 on their stock Zs.

Guess we'll just have to wait until the dyno challenge is done to see how much the Mustang dyno was increasing the numbers by.

zland

This situation is really a good thing because we are beginning to really narrow down what mods (and mod combo's) actually create real hp. There is no need to argue or get upset. Together, we will learn quicker and cheaper than apart.

datspeed77

iTrader: (1)

Sorry if I sound like I'm taking this personal. I'm definitely not! I think the dyno is off too. But I'm very happy about the fact that I still put out more than some guys with lots more mods. That's all! Now for the parts, I still have my cats and exhaust manifolds. Even if the dyno was waaaaay off, how do you explain the fact that I have less mods, but put out more power. I would be skeptical too, but Greg, Rich, and I were all there. I was the last of the three to go. I saw a supercharged Maxima go after me with NOS and put out 254whp. But for the mods I have done, I'm definitely happy with the performance.

PhoenixINX

Our local Z...

w/test pipes, nismo headers, stillen exhaust, pulleys only laid down 368rwhp.

I sincerely would recommend you tell this guy to have his dyno calibrated.

jesseenglish

I think you meant 268rwhp

VandyZ

iTrader: (2)

Actually it was 263, wake up Chris!

WashUJon

Over 300 smells like a mis-calibrated dyno to me...

jnifong

agreed!!

Gets a little old to read through the "no it didn't", "yes it did" tennis match to get to the meat of the topic. Cool to learn what is possible out of this car through various set-ups. On the dyno challenge, it would probably be a good idea to do the runs the same way on the next dyno as you guys did on the mustang if possible, same gear etc... And does limited slip on these cars pick up that the front wheels aren't rotating and send a message to the ECU to dial back a little? I know some cars are set-up this way. RX-8 according to mazda is.

Jon

datspeed77

iTrader: (1)

Really like the plenum you guys have! I just want to know if you can explain how I got more whp than Richards Z. Can a dyno recalibrate itself during runs in the day. I went probably an hour after Richard did. Also, would the dyno get screwed up after each run, increasing and decreasing readings. The reason I ask is that a Maxima that was supercharged and squeezing only put out 254whp after I went. I figured it would put out much more. So my dyno was sky high, then his was really low. Just don't get it. Don't know too much about how dynos work, so any answers would be greatly apreciated! Thanks.

GaryK

I don't know if anybody's already brought this up...the dyno might be innaccurate or read differently from others in general, but it also appears to be inconsistent. Two different things. Some of the cars dynoed may get numbers that are correct, while others don't for one reason or another.

I think its great that the guy got 310 whp, but if it put that down with his mods then a car with ati would probably be in the neighborhood of 410 whp on the same dyno. I'd love to see what these Mossy cars get on a well known Dynojet. It would be nice if there were a simple combination of bolt on na mods that put down 300 whp, but that's really just a pipe dream.

PhoenixINX

Sooooo tired...

failsafe

Interesting thread. I don't think anyone here doubts that you laid down 310 rwhp. You've got sheet proving it. However the fact that your car with I/E/P/Y-pipe put down 9 more hp than Richards car with I/E/C/FW/H/P should have raised a few eyebrows from the dyno techs and anyone else at the dyno day. I'm not doubting your car- you very likely may have one of the most powerful VQ35 engines in the country. But I'm with mcduck- You shouldn't be seeing 50+ rwhp from a CAI, exhaust, Y-Pipe and pulleys. With the numerous companies that have released exhausts for the 350 and the countless hours of R & D spent by the numerous manufacturers someone else would have found this hp.
If I were you I would have been at another dyno shop that very day to see what kind of difference you could find. Sounds like something went faulty on this dyno at some point. If it turns out that another dyno gives the same/similar results I would sign an exlucsive agreement with Apex to sell their exhaust- because everyone on this board will buy one.

samw1978

I'd be happy to pay $3000 for it
50whp!!!

AL350Z

My experience with Mustang Dyno.

My previous car was a Civic Si w/bolt ons

Dynojet 139.0 hp at about 85degrees

Mustang 163.4 hp at about 40 degrees

Yes there was a major difference in temperature but there were 12 cars on the dyno that day and everyone one of us knew right away that it was WAY high figures. Don't flame me, I'm just stating the facts. My Z on a dynojet stock at 95 degrees(portable outside dyno) 232.4 hp.

PhoenixINX

Interesting... if you take THESE numbers... make a ratio... then work this Zs number - You'll find a number of 264rwhp. This is FAR more realistic. HIGH even for the mods, though reasonable.

AL350Z

My thoughts exactly. I would be ecstatic with 264 whp right now(32 more than mine right now) with pulleys and exhaust. My test pipes should be here at the end of next week and I'm hoping for 30hp. Ok, kidding there, but I do hope for 10 whp. That would be way more than the intake, header, full exhaust, and plug wires produced on that civic. 1 whp for all that money. Geez.

lsdunique

iTrader: (3)

This may be stupid but, what about the vehicle weight printed on the dyno sheet? 3300 lbs? could that possibly be the variable between the different cars and readings. I did not think that dyno's required the user to input a weight, nor that it might affect the reading, but I do know many dynos use different technology to get there readings and I know zero about these technologies.

The 3300 vehicle weight on the sheet just popped out at me as I am pretty sure that with a driver, gas, and fluids that the car would weigh a lot more than 3300 lbs.