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To me that looks like a pretty crap tune to be perfectly honest ... waaay too lean. That car's probably detonating badly throughout the rev range. This is what a safe tune should look like (blue line is tuned, red is stock) approximately to have no detonations, although it's an R34 with a stock turbo: http://www.skylinesaustralia.com/forums/in...t&id=165598

Edited by Delta Force

ok got my car back from the tuners few things I was told is that he tunes on a dyno pack not dyno dynamic and he said the line looks like its jumping up and down cause dyno packs use alot more resolution then dyno dynamics, he told me if i put it on a dyno dynamic dyno the line would look a lot smoother......which kind makes sence as the afr on my chart goes up in .2 increments eg 11.8 12 12.2 12.4 over a dyno dynamics which goes from like 11 to 12 ect if that makes any sence hahah! One thing that is weird is the print out I got this time only reads 252kw and he said he didnt even touch the boost just adjusted the fuel??? tell me wot you think of the new graph, cheers

http://i39.photobucket.com/albums/e176/kellyfj/retune.jpg

Dyno thing doesnt stand with me, its AFR's, the wideband doesnt lie! You can make any resolution go up and down, its just the axis you set it on.

AFR's looks a fair bit better there now.

Is this a SR20?

Where is the boost plot?

yeh sr, just got this print out as he said he only adjusted the fuel, boost is on one of the other graphs...do u know why on this graph it reads 252kw but on the tune he did yesturday it pulled 274kw? like I said only thing he adjusted 2day was the fuel not boost???

IT just looks odd, not knowing how SR's behave but that midrange area around 4500-5500 looks like its going to be so meaty, yet it kinda drops off and then picks up again. Just sounds to me like there is something still left top open up

...do u know why on this graph it reads 252kw but on the tune he did yesturday it pulled 274kw? like I said only thing he adjusted 2day was the fuel not boost???

Comparing the two graphs, your tuners knocked half a point worth of fuel in (~12.75 -> ~12.2) where you make peak power ~6000rpm.

The fueling increase could easily account for 20rwkw loss me thinks.

Edited by GeeTR

post-1240-1213918307_thumb.jpg

Maybe its a map sensor tuning issue I am not sure as i love my AFM's...... Its much better and the car would run better. I would also say that if that was cleaned up you should be able to get more mid range and have the boost comming on a bit earlier.

maybe this guy is having issues with your ecu ? its much safer now but still not as rich as i would like it.

is the engine forged?

Looks to me like the range between 3000 - 5000 needs more time spent on it.

Your sampling rate and scale will affect how it looks in graphical form, but reading the raw numbers in a table will still tell you it's jumping around too much. Expect to see some saw-tooth effect, but it's the magnitude of change that I'd be targeting, and get him to work at it.

12.0 to 12.2:1 at higher revs looks OK, and it's easy to see the map richened up beyond 6000.

IMO you should tune it to run sweetly rather than be concerned about an apparent 20kW loss at this stage. You might find with the fueling sorted he can focus on ignition, which is where a lot of power is forfeited.

post-1240-1213918307_thumb.jpg

Maybe its a map sensor tuning issue I am not sure as i love my AFM's...... Its much better and the car would run better. I would also say that if that was cleaned up you should be able to get more mid range and have the boost comming on a bit earlier.

maybe this guy is having issues with your ecu ? its much safer now but still not as rich as i would like it.

is the engine forged?

Hi Guilt-Toy. no the engine is not forged...stock internals

I was told the reason that the mid range section afr's are higher is because right up to 5000rpm the car is not really under much load as its still in the process of trying to spool that big snail and its not until about 5000rpm onwards where it really starts to move and generate alot more power. It makes sence to me cause when I drive the car I can relate to wot he told me??? Of the car is not under to much load up until 5000rpm are thoes afr's safe? cheers

Those AFR's are much safer then before. Being in QLD with the hotter weather i would still like to see 11.8 afr across the board (on boost) for piece of mind, then I would consider the tune safe.

That tune may be considered safe by other tuners who know what they are doing so don't take my opinion as gospel mate, i just like to keep em a bit richer to help cool the cyl's which helps to reduce detonation in case of a fuel surge or a bad batch of fuel etc etc. Its my engine i spent big $$'s so I would rather see 30kw less and nice healthy engine then drive around with a hand grenade under the bonnet.

mind you those AFR's you have now are not what i would call a hand grenade....... but i would not like to run my engine like that.. thats all.

thanks for all ur help I really do appreciate it....I dont think his guna be happy if I keep hassling him but his has promised me that thoes afr's are now safe and he will be the one paying the bill for the engine rebuild if it does blow as I have told him ova and ova make sure the tune is safe....

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