Dyno Graph Guru's please

[Greddy-Matt]

Hi guys finally got my tubby on the RR last weekend, and overall things look pretty much as they should.

Just have a few questions on the graphs if anyone can clarify for me?

Ok so the graphs:
Bhp / Torque:

BHP/Air-fuel

Boost

[Caribbean_Blue]

What are the questions?? All looks pretty neat to me.

Power and Torque are nice again boost still very good.

I'd be happy.

[L0rdMike]

My Rev3 Turbo made 260 on standard boost with just a downpipe and mongoose on the same rollers.

[Greddy-Matt]

So what I'd like to know is...

Im slightly confused with the Air / Fuel curve, I would have thought that as the revs increase fueling would be linear with an upward curve the as the boost increases? ie run leaner at the top end? ie higher the boost the higher air to fuel ratio?

Secondly, im very happy with it but my Torque figure is almost identical to that of my Bhp? Is that normal? I always thought these engines made less torque than power?

Cheers

[Greddy-Matt]

Also I 've just got a manual boost controller to go on and Im going to run it @1.1 bar am I right in thinking that a 0.2 bar increase should be around 20bhp increase?

[cantfindausername]

I really don't like the look of that A/F graph Matt!

here is mine from the same RR. Notice how its a lot more stable. Yours even drops off the graph at the end by the looks of it. Also, you want the mixture to stay relatively flat. Although more air and fuel is going into the engine, the mixture should still be the same (or as close as dammit)

[Greddy-Matt]

Yes mate yours is more what i thought it'd look like!
So looking at this its basically am I right in saying its running a little lean low down and overfueling a fair bit at the top end??

[cantfindausername]

My understanding is its the other way round mate. Running rich early in the revs and leaning right out as it tops out. But my understanding could be wrong.

[Greddy-Matt]

Oh so maybe not such a hot idea to fit that boost controller and up the boost just yet

Bu88er....

What do I get checked then?

[L0rdMike]

Oh so maybe not such a hot idea to fit that boost controller and up the boost just yet

Bu88er....

What do I get checked then?

You get that figure with the boost upped?

I got 258 on standard boost and will upload my fuel/air graph in a sec.

I think the lower down the more rich it is, it is a Air to Fuel ratio.

[cantfindausername]

A mixture is the working point that modern engine management systems employing fuel injection attempt to achieve in light load cruise situations. For gasoline fuel, the stoichiometric air/fuel mixture is approximately 14.7 times the mass of air to fuel. Any mixture less than 14.7 to 1 is considered to be a rich mixture, any more than 14.7 to 1 is a lean mixture

Sorry Matt, I did have it the wrong way round. So yeah it seems like you're really riching out at the end.

Either way though I still think its not as good as it should be.

[Greddy-Matt]

Oh so maybe not such a hot idea to fit that boost controller and up the boost just yet

Bu88er....

What do I get checked then?

You get that figure with the boost upped?

I got 258 on standard boost and will upload my fuel/air graph in a sec.

I think the lower down the more rich it is, it is a Air to Fuel ratio.

No that figure is with no boost controller fitted, have an Apexi intake, GReddy intercooler, downpipe and Blitz Nurspec, its boosting to 0.9 at the moment

[Greddy-Matt]

Phew thats ok was panicking there, drove it pretty hard at the weekend, gulp....

At least if its over fueling its not going to blow its self to bits.

So if it is overfueling it could be smething simple like an O2 sensor?

[L0rdMike]

They run rich as standard. My 2 A/F graphs look more or less the same as yours.

[cantfindausername]

Yeah the run rich, but do you think Toyota would put a car out with a A/F all over the place like that? I don't.

If it was my graph like that I'd be investigating it, and the O2 is probaly the first place I'd look. Plus all the ign. comps.

[Greddy-Matt]

Ok thanks for checking that Think I'm going to have to bite the bullet and get the thing a proper ECU that way I can get it all ironed out and running tickety boo, would explain why I'm only getting about 230miles to a full tank of fuel too...

[Greddy-Matt]

Plus all the ign. comps.

All brand new mate, will start with the O2 sensor, is there anything else to consider?

[cantfindausername]

Yeah I thought they were but wanted to put it cos they'd only get mentioned later on.

I can't really think what else would cause the A/F to be off like that. I started to wonder if something like a bit of timing adjustment might be afftecting the burn in the cylinder, or wether carbon build ups could affect it too. But I did drink a lot last night and I've not had much sleep so I could just be thinking sh!t lol

[L0rdMike]

Just resized them now. Should take better care of them, they are a bit grubby.

[Greddy-Matt]

Yeah the first one looks a little sketchy but the second one is pretty smooth.

Ant is your graph using the standard ecu? I might get the timing checked again anyway, I know I need the tensioner adjusting because it squeals like a pig in the wet so it might have slipped?