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I posted this is msf and I can't post the datalog files here so I added the link to the other post with the datalog if you would please take a peek! Thanks

So I've driven about 50 miles so far, and I figured it was time to do a few WOT runs with the new map. I flashed the stage 2 + TIHSF 93oct the other day, and have been doing some datalogging. I posted my first 10 short datalogs in another post.

I hit WOT briefly a few times on this last datalog... it was only a 5 minute drive after the car was warmed up. I only had 4 instances of any knock on this log, 3 of which occurred during WOT. The good news is that the highest reading of knock was only 0.35, so that's really good.
I was more concerned about my fuel pressure... it hit 1,830 PSI for the DI fuel pressure! I noticed the fuel pressure went over 1,700 PSI in a few places. Is this too high? Do I need to buy that CP-E upgraded fuel pump? I hope not bc I want a fmic next!

Thanks for the input guys!!

Doug


First AP datalog @ WOT - Mazdaspeed Forums
 
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Too high fuel pressure is not an issue here. I wouldn't even worry about the 21 psi UNLESS it's coming on in a sudden spike.

Edit - just checked out your datalog and you've gotta get the boost curve more smooth. You went from around 0 to 21 in less than 1 second ... THAT is what will bust a rod. Get a smooth progression of boost instead of the spike.
 

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nah man the fuel pressure is sweet, it's when you start dropping pressure is when you need to worry. The guys with pump upgrades are looking for 1800-2000 so you're sitting pretty. Like LBV said I guess try and use ATR to smooth out the boost curve.

The even better news is the knock that is almost non existent. Overall how does it feel?
 
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You WANT your fuel pressure to be high. It's people that have fuel pressure dropping to 1400 and below at WOT that need a new pump.

But yeah you need much smoother boost curves. I run 21 psi, but I really don't do full boost below ~3400rpm and it's quite gradual. Large, sudden changes in load make an engine unhappy.
 

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Discussion Starter #5
Cool thanks guys.

How do I smooth out my boost curves now? I haven't gotten that far in ATR yet. I can read through that, and whatever you guys suggest?

Oh, and the car feels good. I'm a little nervous just driving it "normal" until I get this map flushed out. I don't know what I'm doing, but I'm ready to learn. I want it to be safe more than anything. I'll stay out of boost until I figure out how to "smooth" the boost curve.

Thanks again guys!
 

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About smoothing the boost curve... the COBB OTS maps (at least Stage1+SF 93, which is my base) have a fairly steep increase in requested load from 2000 through 3000 RPM for 1st, 2nd and 3rd gear. I wonder why COBB didn't smooth the load curves a bit more if reaching full boost so fast isn't a good thing.
 

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I posted this is msf and I can't post the datalog files here so I added the link to the other post with the datalog if you would please take a peek! Thanks

..........

Thanks for the input guys!!

Doug


First AP datalog @ WOT - Mazdaspeed Forums
First comment is to make sure you edit your logs down to something reasonable to look at and if you're concerned about WOT conditions, you MUST hold it there for at least 4-5 sec for all to stabilize. STOP playing with the throttle pedal and log with it in a fixed position, preferrably WOT and include a few frames just before and just after the WOT event.

After editing your file down to something reasonable, it all looks relatively fine. The slight boost spike is/was at a shift point or at least when you were jockeying the throttle and when you got back on the gas, so no big deal. Now that said, you need some fine tuning in your entire map to get the most out of it and keep it relatively safe. That is going to take more effort than posting up a few logs and asking for help. You MUST read and understand the ECU/Tuning information posted on the Cobb web site and their forum. You could also spend a few weeks reading all the threads over on MSF concerning ECU & tuning. It is rather a learned skill to tune a car, which is why people pay lots of money for others to do it for them.

There are several people on these forums who can help you in detail, but you MUST have a clue before you start or you could make a big mess for yourself.....

Edit for the NO Thanks button: Hey douche, I'm trying to help you here. How many responses have you had over on MSF? They aren't even taking the time to look at your logs after the first time you put up 10 or so useless logs. How many viable response did you get on that one?
 

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About smoothing the boost curve... the COBB OTS maps (at least Stage1+SF 93, which is my base) have a fairly steep increase in requested load from 2000 through 3000 RPM for 1st, 2nd and 3rd gear. I wonder why COBB didn't smooth the load curves a bit more if reaching full boost so fast isn't a good thing.
Because people bitched that they lost the "wild child" feel, so they changed the OTS maps back to the stock-ish "kick in the pants" feel tune.
 

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Discussion Starter #9
First comment is to make sure you edit your logs down to something reasonable to look at and if you're concerned about WOT conditions, you MUST hold it there for at least 4-5 sec for all to stabilize. STOP playing with the throttle pedal and log with it in a fixed position, preferrably WOT and include a few frames just before and just after the WOT event.

After editing your file down to something reasonable, it all looks relatively fine. The slight boost spike is/was at a shift point or at least when you were jockeying the throttle and when you got back on the gas, so no big deal. Now that said, you need some fine tuning in your entire map to get the most out of it and keep it relatively safe. That is going to take more effort than posting up a few logs and asking for help. You MUST read and understand the ECU/Tuning information posted on the Cobb web site and their forum. You could also spend a few weeks reading all the threads over on MSF concerning ECU & tuning. It is rather a learned skill to tune a car, which is why people pay lots of money for others to do it for them.

There are several people on these forums who can help you in detail, but you MUST have a clue before you start or you could make a big mess for yourself.....

Edit for the NO Thanks button: Hey douche, I'm trying to help you here. How many responses have you had over on MSF? They aren't even taking the time to look at your logs after the first time you put up 10 or so useless logs. How many viable response did you get on that one?
Keep your pants on Fordza1. I appreciate the help, but you don't have to be all self-righteous about it :thefing:
 

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Because people bitched that they lost the "wild child" feel, so they changed the OTS maps back to the stock-ish "kick in the pants" feel tune.
That's weird that they would do that. So, now we have to tune them back to 'smooth' by ourselves?
 

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This was mostly a matter of throttle map changes and I don't know if they altered the load tables as well between the maps, but the result is essentially the same, where you get a very sudden onset of high requested load, giving you the kick in the pants feel that people wanted back.

And it's not weird. Customers overwhelmingly cried that they wanted back the sudden onset of power feel, so Cobb gave in and gave it to them.

It's a very simple matter of smoothing out the necessary mappings though so it's not a big issue. While "off the shelf" tunes are a nice idea, each car ends up being different even with the same mods, so it's always a good idea to understanding the tuning process yourself and to know what you're changing before you change it so that you can have exactly what you want.
 

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I like the smooth throttle compared to the kick in the ass stock table. Boost is also more controllable doing this.
 
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