Tuning beyond WOT

[Visco]

Tuning beyond WOT

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'05 GSR- Stock turbo, TBE, HFC, MBC-22psi, Walbro - 91 pump gas

I have already tuned my car for WOT at 0 knock.

However, I am anal about my car and datalog all the time. I have partial throttle knock in the 2000-3500 rpm range at load levels 70-100 off-boost and partial boost. I have made no changes to the AFR (=stock AFR), but have found that I have significantly adjusted the timing in those ranges to avoid any knock. Reminder- this area of the AFR and Tiiming table was previously unmodified and identical to stock.

I have run enough logs to determine that knock in these areas is consistant.

I feel like this is a prudent thing to do from a reliability standpoint, but have not heard about people tuning beyond WOT runs.

I daily drive this car, so like many others, it sees more time at low boost-partial throttle than WOT.

Please advise

[kimletrim]

If your goal is to have zero knock all the time, you better make sure you are running higher than 91 pisstane gas all the time.

[Visco]

That sucks. Am I going through a detune process on my high octane map that very few people care to address? Does everyone just allow the car to knock into low octane maps?

[MoReRyCe]

how many counts of knock are you getting tht you are so worried about it...?

[nj1266]

I agree with Bryan. That is the way I tune my car. I do not see the point of having advanced timing only to have the ECU pull the timing out when the car knocks and ending up with the timing that the car really wants. Why put your Evo through this? Give the Evo the timing that it wants rather than what you think it wants and you will have a very smooth and consistent powerband.

[Blak94GSX]

Yeah the goal is to tune it for 0 knock at WOT, but you have to be careful not to reduce the timing too much. The ECU will show knocksum periodically, you don't want to just pull timing everytime you see some knock on the logs. You should only reduce the timing on the tables when the knocksum appears consistently.

Also, the knocksum bleeds off slowly, so only reduce the timing where the knocksum increases. Going up through the RPM band until you have 0 knocksum (barely) at all RPM points. If you get the occasional knocksum spike that doesn't appear in every pull then don't worry about it.

The key is to make sure you have a little knocksum everywhere first, so you know you have enough timing, then you slowly decrease it until the knocksum is 0.

If you log a stock EVO you will see there is crazy high knocksum. The ECU evetually sorts this out by decrementing the octane value and mixing the low and high octane tables to find the right amount of timing. When you tune it for a specific type of fuel, you are shortcutting the process to make the High Octane timing table be the "right" amount of timing so the ECU doesn't have to go through the learning process.

[Blak94GSX]

To address your original question, yes you need to tune at all of the load columns. The EVO isn't just a drag racing car, you want to be able to use every part of the tables. The basic step is to start with the boost turned down and then go through each of the load columns until you have the range you are going to use with that fuel covered. For example, you don't need to tune the 260-300 load columns for pump gas since you hopefully aren't running that much boost, but you should still scale them appropriately, meaning if you reduced the timing at 220 for 6000 RPM, you should reduce the timing above that load also so it is all proportional. When you look at the timing table in 3D, it should have smooth blends between all points. Like a wet blanket draped over a chair. If it looks like the Manhattan skyline then you have a problem.

As for the vacuum range, typically this works pretty well with the stock values unless you have made large changes to the operation of the engine, like crazy midrange cams, or going to a 2.4L motor, etc. Even then, it doesn't usually require many changes.

[Visco]

At and estimated 22psi peak, I am seeing loads in the 260s and even one or two in the 270s uphill with lots of weight in the car.Â* Is this an indication that the boost is too high?Â* I am planning on going to the JDM map sensor to get a better read on boost levels, however my current AFR map is based on the currently set boost level.

Thanks everyone for your inputs. It sounds like I am on the right track.

[Blak94GSX]

Naw that's fine. Just tune whatever load columns you are using. The point was that you don't need to crank up the boost to 35PSI to tune every load column, just those you are going to realistically use.

[CASH$ MONEY]

lol, tuning is in another world.... 8)

[azul gsr]

you must be really bored to respond to an Oct 07 topic huh?

[CASH$ MONEY]

you must be really bored to respond to an Oct 07 topic huh?

papa, dont forget this this Cash Money....
!!!!! hehe

[littlejap33]

just make sure ur A/F ratio is good and keep an eye on boost and knock

[WOT]

if its knock in part throttle, remove timing until it stops & be certain your afr's are in check while this is happening.

does it hapen only when you roll into it @ that particular area or any time you pass through that region with a constant throttle position?

dont get worried about loosing to much power in the paret throttle area anyway. if you want more power, press down more on the pedal on the right!