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Time based access TPSdot and ms pulse width

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Thank you for the feedback!

440cc* injectors, I am not sure if that changes the math.

I wish I had my laptop with me so I can adjust things real time.

Could I bother you for how you arrived at 4.8ms? Is that just a bit of an arbitrary decision compared to halfing it? The hp and tq number seems to be quite low compared to even modest estimations. Would it be worthwhile to overestimate in the generator then have auto tune pull fuel? My friend with the older less efficient, slightly smaller model (56 vs 57mm)  turbo on his single cam 2.7L at 10lbs of boost is making an estimated 320hp to the wheels on virtual dyno. My slightly bigger more efficient turbo on my twin cam, 3L is making 13-15lbs at the moment, so I estimate about 350hp with similar torque. 

Currently my tune is set to 3.8ms with the VE tables doubled from previous. 

I will change it tonight to 4.8ms req fuel, and generate a new VE table with an estimate of hp and tq.

Then richen it up in boost (above 100kPa) by adding 20% via the scalar

Spark table I will pull 3 degrees, so retard timing by lowering the numerical value under boost from (19 down to 16 for example), under 100kPa.

Threshold was at 20 on one of my accel graphs I wonder if it got bumped while I was playing with multiple files, but I will verify.





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I meant reduce spark table 3 degrees overall when Boosting IE: over 100Kpa. "Under Boost "  meant when ON Boost.

I used a PW calculator developed for Haltech. It's very good. Numerous other online calculators and they all come up with the same answers. I enter the figures to get a Master PW and then add about 1ms to take care of the additional enrichment values. 4.8ms was a figure I had derived from a L28 Turbo with 440cc injectors.  Another 200cc in your engine won't make a lot of difference in the Req-Fuel calculation . 

The tables I posted were for 440cc injectors. 

Here is the Injector Calculator I use, Note : For Sequential injection use an ambient temperature figure of 25c. For Batch Fire use 35c

Injection Time Calculator V2.0.xls

Edited by Chickenman

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Tuner Studio' VE table generator doesn't always.  handle high horsepower numbers well. It's not a true VE calculator. It can sometimes calculate some truly bizarre VE Tables when large HP and Torque numbers are added. If you use the MS-2 VE Table as generated by TS, it always seems to make the non-boosted area overly rich ( Too high of cell numbers ) . Particularly if you don't have accurate Dyno figures. Of course how do you get accurate Dyno figures if you haven't gotten the engine running properly yet? Catch 22. 

As a result I find it more accurate to enter the stock HP and Torque figures and  generate a table. That is normally pretty close up to 100 Kpa and at least makes the non-boosted area driveable. In boost I'll add an Extra 10 to 20% increase to the rows in ascending order. Just to be sure it's Rich enough. Always better to pull fuel out under Boost than to have to add it in. Auto-Tune is not fast enough to correct a Lean condition under WOT Boost.

Actually, I want to double check that 4.8ms Tune that I posted. That came off a " problem child " car and I really had to pull the Req-Fuel down to get the VE Table even remotely accurate and with some resolution. As TS originally calculated it we were down in the 12 range at idle... which is not good. 

As mentioned though. The Req-Fuel calculation is just a number in an equation. Reduce it to get more resolution in the VE cells at the low end. Leave it alone if the resolution is OK. 




Edited by Chickenman

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