tuning with 50 trim

[GreddySpyder]

My mods are in my profile. I just installed my PTE 50 trim yesterday and i'm still trying to fine tune things. I would think with a massive turbo like this I should have to get into some positive fuel trims at some point, but they are staying negative across the board and i am still backfiring and hesistating from roll on acceleration. i know that settings will be different for different cars, but what kind of settings are others running with the 50 trim? As a side note what kind of cooling fans is everybody using? My passenger side fan won't even come close to fitting with this turbo.

 

[brads]

Originally posted by GreddySpyder
As a side note what kind of cooling fans is everybody using? My passenger side fan won't even come close to fitting with this turbo.

Could you take a pic of the clearance issue? I'd be curious to see what sort of room you have.

I don't have a PTE 50 trim, but my turbo had similar fitment issues due to wastegate actuator location. I got a second AC condenser fan and put it on in place of the stock rad. fan, it plugs right in, and bolts up in the same locations.

Brad

 

[redwards]

Originally posted by GreddySpyder
My mods are in my profile. I just installed my PTE 50 trim yesterday and i'm still trying to fine tune things. I would think with a massive turbo like this I should have to get into some positive fuel trims at some point, but they are staying negative across the board and i am still backfiring and hesistating from roll on acceleration. i know that settings will be different for different cars, but what kind of settings are others running with the 50 trim? As a side note what kind of cooling fans is everybody using? My passenger side fan won't even come close to fitting with this turbo.

Um. You still have an Air Flow Sensor. The trims on the AFC are adjustments to what the ECU tells the injectors to dump in. The ECU will automatically dump in an assload more fuel if you get an assload more air, you don't need to adjust the AFC for that.

I have a 50 trim, my AFC is at about -30% across the high throttle range with 660cc injectors (which, not coincidentally, are about 30% larger than stock 450cc injectors). I also hacked out my MAF, so the car is running considerably leaner than it would be with an unhacked MAF. After hacking the MAF and leaning it out 30% across the board, it's still a tiny bit rich.

If you look at the dyno sheet in my gallery, you can see the Air/Fuel Ratio is the second line. It's not a great spread, but we didn't do ANY tuning before we put that down, and the graph only charts 10:1 - 15:1.

 

[redwards]

Passenger side fan? Most people I know have no driver's side fan, because the IC piping and/or wastegate gets in the way. Nothing wrong with only having one fan.

 

[GreddySpyder]

Originally posted by redwards
Passenger side fan? Most people I know have no driver's side fan, because the IC piping and/or wastegate gets in the way. Nothing wrong with only having one fan.

yes the passenger side fan, the turbo outlet sticks out too far as it is to even come close to putting the huge main fan back on. I have the one fan wired to stay on at all times right now and it is doing ok as long as i don't idle with the AC on, but it is hot as piss around here so i want to do something ASAP. What size and type of fan would be optimal for replacing the passenger side fan?
Thanks for the info redwards, my brain was asleep when I was thinking of what the percentages were actually saying. I leveled everything out to around 30% for the time being like you said and it is pulling much smoother and harder already.

 

[Mike 99GSX]

I have an almost identical setup as you. Check profile but I've got a VPC/GCC so things may be different. I've got an almost dead flat A/F curve of 12.5 to 1 from 4800 to redline my settings are VPC Gain 0
GCC 700= -4, 2400= 0, 4100= +2, 5800= +6, 7500= +8.

 

[aves911]

I've got the same timing advance while the turbo is spooling that you do. It was explained to me that the ECU doesnt drop timing until it detects steady boost pressure, i.e. when you hit max boost.

So pretty much, unless you have a standalone and can tell it when to go into open loop mode, adjusting the timing on the stock ECU won't do anything because it is in closed loop mode until you hit full boost.

As far as fans go, I just used my AC (Driver's side) fan in place of my main cooling fan. Works great, no overheating problems this summer, I live in Kentucky, even when I am stuck in traffic on 100 degree days.

I'm just curious for those of you who have tuned your 50Trim, what kind of boost are you able to run on pump gas (93, 94 octane). I am seeing too much knock at 20psi before I settle on running less boost, I just want to see what other people are able to do.

Thanks,
-Jacob

 

[aves911]

I've got the same timing advance while the turbo is spooling that you do. It was explained to me that the ECU doesnt drop timing until it detects steady boost pressure, i.e. when you hit max boost.

So pretty much, unless you have a standalone and can tell it when to go into open loop mode, adjusting the timing on the stock ECU won't do anything because it is in closed loop mode until you hit full boost.

As far as fans go, I just used my AC (Driver's side) fan in place of my main cooling fan. Works great, no overheating problems this summer, I live in Kentucky, even when I am stuck in traffic on 100 degree days.

I'm just curious for those of you who have tuned your 50Trim, what kind of boost are you able to run on pump gas (93, 94 octane). I am seeing too much knock at 20psi before I settle on running less boost, I just want to see what other people are able to do.

Thanks,
-Jacob

 

[brads]

Originally posted by aves911
I've got the same timing advance while the turbo is spooling that you do. It was explained to me that the ECU doesnt drop timing until it detects steady boost pressure, i.e. when you hit max boost.

Not quite true, the timing will drop as the boost builds. It doesnt wait to drop until a steady pressure is reached. If you have a logging system like DSMLink, you can clearly see this. But also, just from the way the timing maps are set up, its pretty clear this is how it works.

Brad

 

[Mike 99GSX]

I have been researching this to death and I know Brads is right. I think I may have figured out my spoolup problem. I've been told that the spring in my Tial is likely too weak and I may need a stiffer one. I'm trying to get a hold of AGP as we speak. I think I was one of the first people to get one of the newer 38mm gates. Maybe its a spring match problem with the new model.