Jump to content
SAU Community

My 34's First Dyno

G_Force

By G_Force,
in Engines & Forced Induction

 Share

Recommended Posts

Abo Bob Grand Master

Abo Bob

Posted
Posted
Nope.

I've never seen someone "average" runs and print that out.

Not saying its not possible... But your run is all over the place which is basically a poor tune

I have. Doesn't mean that this is relevant here though. Sorry to have introduced a possble furphy to the thread.

G_Force Community Regular

G_Force

Posted
  • Author
Posted
Mate; my friend's R34GTT in AUTO with nothing but a Std ECU ran 194rwkw and the curve was A LOT smoother than yours :)

Glad that my immediate reaction from seeing your graph is shared by a few others.

You have a PFC; your graph should be smooth as all hell!

Hmmm... so should i perhaps bring it back to the tuner and tell him to smooth the curve our & drop the boost a lil... how do they smooth it out just out of curiosity? Also why do u guys think that the boost is dropping off towards the top end, could this be turbo inefficiency?

Bass Junky, i didnt think that the lower 2nd graph could be a reading of torque coz if i converted the figures in LbFt to Nm i'd have a peak torque of 1550Nm. Altho that would be nice if it were only true.....

Thanks for all ur comments/advice btw...

Bass Junky Grand Master

Bass Junky

Posted
Posted

G-Force.

Normally on a dyno graph you are interested in four things.

Power either kW or hP at the wheels

Torque either ft/lbs or nm at the wheels

Boost in either PSI or Bar

AFR only in Air : Fuel

don't worry too much about the numbers of the torque as you have to remember that you are going through a gearbox and rear diff which changes the ratio and stuff of the torque.

It's only a measure, not really an exact number, and at the end of the day, Power is simply a measure of Torque over time.

Bass Out

G_Force Community Regular

G_Force

Posted
  • Author
Posted
G-Force.

Normally on a dyno graph you are interested in four things.

Power either kW or hP at the wheels

Torque either ft/lbs or nm at the wheels

Boost in either PSI or Bar

AFR only in Air : Fuel

don't worry too much about the numbers of the torque as you have to remember that you are going through a gearbox and rear diff which changes the ratio and stuff of the torque.

It's only a measure, not really an exact number, and at the end of the day, Power is simply a measure of Torque over time.

Bass Out

Dont they normally do the dyno run in 4th gear which is close to a 1:1 ratio? Correct me if im wrong, im no dyno expert. Im just interested in wot that 2nd graph was reading thats all.

Back to the more important question. Should i perhaps bring it back to the tuner and tell him to smooth the curve our & drop the boost a lil... how do they smooth it out just out of curiosity? Also why do u guys think that the boost is dropping off towards the top end, could this be turbo inefficiency at 14psi?

Cheers

Bass Junky Grand Master

Bass Junky

Posted
Posted

Remember your diff is about 4.11:1 hence, massively inflated torque.

Drop boost a little. I made 200rwkw on 11 psi and you've seen my graph, it's nice.

the boost is dropping off because your turbo aint got no more to give.

G_Force Community Regular

G_Force

Posted
  • Author
Posted
Remember your diff is about 4.11:1 hence, massively inflated torque.

Drop boost a little. I made 200rwkw on 11 psi and you've seen my graph, it's nice.

the boost is dropping off because your turbo aint got no more to give.

Aha.

Wot mods r u running in urs Bass? Ive been looking thru numerous other dyno graphs on the forum, it does look like mine's rough as hell in comparison.

If i brought the boost back to round 12psi would i still be able to achieve close to the same power figure? I'll give my tuner a ring today and see wot he's got to say. Wot should i say to him to smooth out the power curve? Is it a matter of correcting MAP figures?

Bass Junky Grand Master

Bass Junky

Posted
Posted

When I was making 200 I had FMIC, Dump pipe back exhaust (not turbo back) Power FC, PFC Boost kit, and that's about it.

The roughness of the tune will be a combination of AFR and Timing.

That's basically what a tune is. How much fuel, and how much timing at different load points. Load points are supplied by the MAF sensor.

The AFR is rough as guts and I reckon the ignition timing is going to be all over the place.

Here's what I'd do.

Go into your PFC hand controller and write down the ignition timing and fuel map.

So get an Excel spreadsheet and put 1 thru 20 on the top and 1 thru 20 down the side.

Going in the ingition timing map and write it down number for number.

Same with Fuel.

Then punch those numbers into the spreadsheet and graph it 3D.

the progressions and gaps between numbers should be smooth and clean.

Not big jumps up and then down.

Try it out.

You'll learn a lot about tune maps.

Bass Junky Grand Master

Bass Junky

Posted
Posted

Oh yeah, and the turbo doesn't make any more power at 14 psi than it does at 12 psi as its out of it's efficiency up top.

You'll make a little bit more in the mid range, but you'll overspeed the turbo and it's a recipe for busting it.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • GTSBoy
      WGNC34 - floor mats

      By GTSBoy · Posted

      I dunno about that as a blanket statement. Pitwork is Nissan's "Nissan genuine" thing, and for stuff like timing belts, I have found them to be excellent. Of course, for things like oil filters, you always use proper trusted brands anyway, not whatever the OEM has taken to using.
    • MBS206
      R34 Skyline climate control unit transistor

      By MBS206 · Posted

      Ahhhh... If you were putting 12V to the led in there, that's likely made it very unhappy. Chances are how you put power, was 12V across an LED that's meant to only have about 20mA through it at peak, and a forward voltage of about 1.8 to 2.4 volts. That circuit is likely only a 3V3 circuit, and will have a resistor in series with the led too. That's my guesstimate on that light, without having touched one.
    • Murray_Calavera
      Tein Circuit Master- rebuild worth it?

      By Murray_Calavera · Posted

      Another vote for installing them and see how you go.  I mean, you already own them, why would you not fit them? 
    • Duncan
      NC MX5

      By Duncan · Posted

      I have had too many of those over the years, my cars have a toolkit or at minimum a cheapy multi tool thing because its too easy to be snookered by some stupid plastic clip that stops you checking the battery terminal isn't loose.
    • Duncan
      WGNC34 - floor mats

      By Duncan · Posted

      Basically, if there is a part# on the nissan catalogue, it is a genuine part. There is a thing called "new old stock" which is stuff made years ago but never sold (or landfilled), but it is super hit and miss what you can buy. Other than some expensive Nismo stuff there is nothing new being made that suits these cars. The only time to be a little careful is (mostly in the US I think, but maybe Japan too), Nissan started rebranding some cheap crap maintenance parts like oil filters as "Pitworks"; stay away from them, if you are buying cheap just buy whatever the local car parts shop carries The three part numbers have an explanation on Amayama: 0V005 is auto, base style 0V015 is manual 0V505 is auto, hectic momo branded ones, maximum F&F points there!
×
×
  • Create New...