Bigger turbo means lean mixture?

Discussion of technical issues and ideas (engine, chassis)

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djtreble
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Post by djtreble »

In all of this I have just worked out your problem Draco.

Your car is mapped for higher heat air coming through at 0.5 bar. Now that you are running the bigger turbo, your air temprature is lower (more dense) and you car is fueling thinking there is colder outside air (overfueling for the 0.5 bar pressure).

I'd love to find out if I am right or not after you get your car re-mapped, would help in my learning to map cars.

And to your post Gary, that is fine as it takes longer to get up to full boost (laggy) so the air flows longer, and the ECU fuels for longer as result.
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POWDER
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Post by POWDER »

OK, Now saying it like that makes more sense then, the mass of the air changing due to lower or higher air temperature due to the more easily cooled larger surface area of the turbine ? OK, Now I'm getting that part of it.... But would that really be such an extensive change in temperature then?
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djtreble
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Post by djtreble »

It doesn't take much to mess up the fueling on a car mapped for running on a MAP sensor as it has a very sensitive map. Removing a decat, changing a pipe's length or diameter and most small changes requires a remap.

Running a MAF/AFM sorts out these small changes automatically.
So if you aren't planning on going for more than 500/550 BHP, it's worth using a Z32 AFM in my opinion and is the way I will be going.
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Draco
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Post by Draco »

This might be one of the reasons, I have a engine and air temp compensation map, on colder air and engine temps the maps added some fuel for colder temps....maybe... :wink:
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djtreble
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Post by djtreble »

That I believe is the reason bud 8)
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Draco
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Post by Draco »

djtreble wrote:That I believe is the reason bud 8)
Hope it's as simple as that....
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djtreble
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Post by djtreble »

Draco wrote:
djtreble wrote:That I believe is the reason bud 8)
Hope it's as simple as that....
So do I for more than one reason
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Post by POWDER »

so with a little playing as far as the compensation maps are concerned, Draco could get his car going like one boing again. . . . Nice one...
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Post by Draco »

POWDER wrote:so with a little playing as far as the compensation maps are concerned, Draco could get his car going like one boing again. . . . Nice one...
I guess I will find out this weekend :lol:
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POWDER
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Post by POWDER »

Draco wrote:
POWDER wrote:so with a little playing as far as the compensation maps are concerned, Draco could get his car going like one boing again. . . . Nice one...
I guess I will find out this weekend :lol:
ha ha, u go boi, tune dat biatch !!!!! :twisted:
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Post by Draco »

POWDER wrote:
Draco wrote:
POWDER wrote:so with a little playing as far as the compensation maps are concerned, Draco could get his car going like one boing again. . . . Nice one...
I guess I will find out this weekend :lol:
ha ha, u go boi, tune dat biatch !!!!! :twisted:
Who you calling a boi :lol:
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Draco
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Post by Draco »

Thanks for all the ideas and help guys...!!!
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POWDER
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Post by POWDER »

No thanks required cuz, Just keep us updated, I'm sure all of us would love to know what the problem actually is.......
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Draco
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Post by Draco »

Had some limited time this weekend, soldered all the wires that I made up just to get me home, fastened battery properly and with some help over the phone from Charl sorted the fuel pump relay.

Then I started the car, first start was always dodgy before, idled very low and blowed white smoke untill hot, now I udjusted the engin and air temp compensation as well as the battery voltage compensation....

Now when I start, idles good and the only "smoke" you can see is steam as the exhaust warms up, idles and starts very good in cold temps. So all the adjustment of the compensation maps seemed to do the trick, also adjusted the fuel acceleration trim maps.

Couldn't drive over the weekend, the normal issues :roll: , so I decided to drive it to work today, on lower revs starting to boost has hesitation....according to data logging might be little lean there,,,,but when it really goes into boost...whalla....a bit lean now after I leaned all the compensations but is boosting like a mofo, did not have a clue where the boost would be...according to fong kong guage over 1.5 bar :shock: ...according to wolf 22.4 psi.... :?

That is a bit to much....but let me tell you one thing, climed on the highway and gave enough pedal to get the boost going and I accelerated to 220 in no time...took my foot off and started to brake...got to 120 again and saw this super bike come in next to me, obveously he saw me when I climed on the freeway and started pulling....just pulled up next to me shaking his head in appreciation and giving me the thumbs up!!!

Now it's getting her to the dyno and getting the boost right and the tuning spot on....
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POWDER
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Post by POWDER »

Friggin "A" Bud, thats awsome, always fun having a Bike appreciate the power of our cars, lol


N E Way, u better take a Dyno Vid and Road vid when done, we wants to check it......
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