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Discussion Starter · #1 ·
hello...im trying to tune my turbo'd zx3...i have the sct prp...i cant seem to get this tune right at all..i already blew one engine..not looking to blow another..i have my afr pretty good it never goes above 15..but for some reason whenever i give it a little gas over 3000 rpm it feels like it bogs out?! what would this be caused by timing? i got a base tune from tom..im just very new to the tuning world and pretty much have no clue...most of you guys on here are pretty cool i was just wondring if you guys could help me out at all toms a pretty busy guy i dont like bugging him all the time...thanks alot guys

Joe
 

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As far as the STFT, with boost, you should be around 1.25 to 1.3 at WOT. At idle or low RPM's when you are not boosting, it should be ok to have STFT of 1, but as soon as you boost your STFT should be richer. Do you have adaptive on or off. What ratio are you running in the base fuel table? you should set it for at or below 12 (0.82) for all TP's where you are in boost. I changed my TP for WOT too 400 and set the base fuel table to 0.82 for all rpm that you will be making boost. Now this will not make the STFT stay at around 12 A/F ratio unless adaptive is turned off, but it should be close when you go WOT. If you keep adaptive on I think you will see close to 14,64 at idle or low rpm and around 12 or less at WOT with a value of 0.82 or less in the base fuel table.
 

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Springbuck said:
As far as the STFT, with boost, you should be around 1.25 to 1.3 at WOT. At idle or low RPM's when you are not boosting, it should be ok to have STFT of 1, but as soon as you boost your STFT should be richer. Do you have adaptive on or off. What ratio are you running in the base fuel table? you should set it for at or below 12 (0.82) for all TP's where you are in boost. I changed my TP for WOT too 400 and set the base fuel table to 0.82 for all rpm that you will be making boost. Now this will not make the STFT stay at around 12 A/F ratio unless adaptive is turned off, but it should be close when you go WOT. If you keep adaptive on I think you will see close to 14,64 at idle or low rpm and around 12 or less at WOT with a value of 0.82 or less in the base fuel table.
There is SOOOOO much wrong in this i dont know where to start , DO NOT watch your STFT at WOT they have NOTHING to do with what your AF is at WOT ,the computer does NOT use the o2 sensor AT ALL at WOT so any feed back would be incorrect and your STFT are for closed loop and WOT is open loop

Leaving your adaptive learining on or off is up to you we dont have 100% controle over all the adaptive tables and there targeted more to emmissions anyway so i allways leave them off and have had less issues

As for the base fuel tables you cannot tell some one "you should set it for at or below 12 (0.82)" because any Focus with the MAF changed may need that setting higher or lower depending on how far off the MAF transfer functions are vs stock setting just because you put a 12.8 into the bast fuel tables DOES NOT mean that is what the AF is going to be at WOT because the ECU does not use the o2 in ANY calculations at WOT

PLEASE misinformation is bad on engines when it comes to tuning and FI , Im not trying to be a jurk here if you have any questions about how things work ask im more than willing to answer any tuning questions

Tom
 

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Hello Tom,

My mistake on the STFT as you use the STFT only for idle and maybe up to 3k rpm's, I must have been asleep, but on the base fuel table and A/F ratio, SCT says to set your commanded A/F ratio in the base fuel table and then ajust your MAF function until it is correct. You can do it the other way around as well I suppose, this way just seems to be easier...

leaving adaptive on has improved some peoples tunes and performance on others it does not.
 

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Springbuck said:
Hello Tom,

My mistake on the STFT as you use the STFT only for idle and maybe up to 3k rpm's, I must have been asleep, but on the base fuel table and A/F ratio, SCT says to set your commanded A/F ratio in the base fuel table and then ajust your MAF function until it is correct. You can do it the other way around as well I suppose, this way just seems to be easier...

leaving adaptive on has improved some peoples tunes and performance on others it does not.
The STFT is used at ANY time the fuel is in closed loop that could be to 5000 or 6000RPM even and will depend on where you have the WOT/open loop trigger set that is why it is important to set your STFT tables so there safe all the way up

I know how SCT sais to set the the commanded fuel tables and there way will work fine the important thing is to get a safe A/F it isnt important how you do this as long as it is done. I just wanted to make sure that people didnt think that the base fuel tables setting if set to say 12.8 that it would do 12.8 , It wont matter if fuel is added to the base fuel tables or the MTF they will both add the fuel with no side effects

Tom
 

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The reason I said 3k is that even stock the TP for WOT is set for about half throttle. All the tunes I have seen lowers that even more, that's why I said 3k, since that or just below that value is where most tunes will go open loop, but yes, I should have specified to the TP for WOT or open loop transition instead of 3k. The problem with working with the PRP is you tend to think only in terms of your own tune.

Thanks for clearing that up Tom :)
 

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Discussion Starter · #10 ·
ok..i have been working on getting the timing right..im getting pretty close...i have found 4 trouble codes over the process...p0141, p0720, p0722, and p1132..somtimes when i give my car a half throttle it bogs out...but then somtimes it doesnt..could any of these trouble codes have anythign to do with that???
 
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