Is it possible to get 330 HP from a 2003 3.2L Engine?

[Smallblock454]

@KRAM36

You're welcome.

Don't forget that your AT-tranny will need an defined amount of variable underpressure to work perfect, and that the intake tube is designed to deliver exactly that underpressure.

Also consider not also the Helmholtz but also the Venturi effect when you do things in a new sophisticated KRAM36 way.

[The Radium King]

I *think* the tip connection is only for vacuum, so not a lot of, if any, air movement through it.

you will need a wideband o2 sensor to measure afrs at wot. your car only has narrowband (ie, measures afr values in/around 14.7). ecu uses feedback from the narrow band sensors to keep afr at 14.7 at idle and part throttle though the use of fuel trims (ltft). this is closed-loop operation.

at wot the ecu wants to add a bit more fuel to keep things cool (ie, an afr of 13 as suggested by jaay). narrowband sensors don't work in this range so the ecu has no feedback on the afr it is providing - it just adds fuel based on the amount of air measured. this is open-loop.

open loop is the most critical, as this is when the engine is working hard and the opportunity for damage the greatest. if the maf is mis-reading air (ie, more air getting in than the maf reads) you may get into a lean situation which can kill your engine (gets hot, detonation occurs, pistons get holes in them).

how can the maf misread air? a larger diameter maf tube will do it. non-laminar flow in the tube can do it (ie, as jay notes, the ecu is calibrated to read airflow based on a certain type of airflow, and this airflow can be modified by bends - or the lack thereof - upstream of the sensor) vacuum leaks can do it, vibration can do it (ie, I thought it was good to have the maf closer to the tb for better throttle response, but this also resulted in the transmission of more engine vibrations) etc.

the thing is, all the factors that affect air metering at open loop operation are present at closed loop operation, so, check your ltfts and see if they are high. If they are then your open loop afrs will be off (my understanding is that the ecu does not use the closed-loop ltfts when running open loop). a little bit of lean operation is ok; Porsche oem afr at wot is 12.5; moving to a 13 should be fine (will result in more power and better fuel consumption) as long as you use a higher octane fuel.

blah blah blah ...

[JAAY]

Radium<<<<<<<<<<< Thank you for the better explanation.

[The Radium King]

Originally Posted by JAAY

Radium<<<<<<<<<<< Thank you for the better explanation.

actually - you are the man here, as you've actually gone in with a piggy back and modified your fueling. perhaps you could help me - does the ecu use the trims established in closed loop operation to modify fueling when running open loop? you could probably determine that by resetting your ecu - as it re-adapts and resets trims, do you see open-loop fueling changing?

[KRAM36]

Originally Posted by The Radium King

I *think* the tip connection is only for vacuum, so not a lot of, if any, air movement through it.

you will need a wideband o2 sensor to measure afrs at wot. your car only has narrowband (ie, measures afr values in/around 14.7). ecu uses feedback from the narrow band sensors to keep afr at 14.7 at idle and part throttle though the use of fuel trims (ltft). this is closed-loop operation.

at wot the ecu wants to add a bit more fuel to keep things cool (ie, an afr of 13 as suggested by jaay). narrowband sensors don't work in this range so the ecu has no feedback on the afr it is providing - it just adds fuel based on the amount of air measured. this is open-loop.

open loop is the most critical, as this is when the engine is working hard and the opportunity for damage the greatest. if the maf is mis-reading air (ie, more air getting in than the maf reads) you may get into a lean situation which can kill your engine (gets hot, detonation occurs, pistons get holes in them).

how can the maf misread air? a larger diameter maf tube will do it. non-laminar flow in the tube can do it (ie, as jay notes, the ecu is calibrated to read airflow based on a certain type of airflow, and this airflow can be modified by bends - or the lack thereof - upstream of the sensor) vacuum leaks can do it, vibration can do it (ie, I thought it was good to have the maf closer to the tb for better throttle response, but this also resulted in the transmission of more engine vibrations) etc.

the thing is, all the factors that affect air metering at open loop operation are present at closed loop operation, so, check your ltfts and see if they are high. If they are then your open loop afrs will be off (my understanding is that the ecu does not use the closed-loop ltfts when running open loop). a little bit of lean operation is ok; Porsche oem afr at wot is 12.5; moving to a 13 should be fine (will result in more power and better fuel consumption) as long as you use a higher octane fuel.

blah blah blah ...

How can I check the ltft? What is too high? Don't I need more miles on the car after the mods (less then 100 miles right now) before the computer sets the ltft?

[The Radium King]

Need help understanding Durametric fuel trim readings - 986 Series (Boxster, Boxster S) - RennTech.org Forums

[KRAM36]

Originally Posted by The Radium King

Need help understanding Durametric fuel trim readings - 986 Series (Boxster, Boxster S) - RennTech.org Forums

I read Loren's response, but how do I equate that info into ltft? Loren doesn't say what the values should be.

I don't understand.

[The Radium King]

Porsche 986-996-987-997 Fuel Trim Information | Callas Rennsport

[KRAM36]

Originally Posted by The Radium King

Porsche 986-996-987-997 Fuel Trim Information | Callas Rennsport

That makes more sense to me.

My readings at idle and engine fully warm.

Range 2 (FRA) Bank 1 = 1.08
Range 1 (RKAT) Bank 1 = 2.86
Range 2 Lower (FRAU) Bank 1 = 1.08
Range3 Upper (FRAO) Bank 1 = 1.00

Range 2 (FRA) Bank 2 = 1.11
Range 1 (RKAT) Bank 2 = 4.13
Range 2 Lower (FRAU) Bank 2 = 1.11
Range3 Upper (FRAO) Bank 2 = 1.00

Not sure which MAF reading he was referring to as there are 2 to read from.

MAF (HFM) danced between 11 to 13
Mass Air Flow danced between 10.9 to 11.7

I'm also getting P0430 on the Quick Test
Porsche Fualt Code 45 Cat Conv. Efficiency Bank 2

[edc]

You could always stick your car on a dyno and get a plot of the afr across the rev range. My afr / fueling seems pretty good as is so it's hard to see aside from a bit more advance where you can make any significant inroads.

[KRAM36]

So I gather from those readings at "WOT" open loop (FRA FRAU FRAO) my AFR is pretty much spot on, but at idle closed loop (RKAT) the AFR is running extremely lean?

[The Radium King]

these are closed loop values - no trims generated when at open loop (no feedback from the o2 sensors, so no trims). your fra numbers look good - oem Porsche is +/- 0.1. from what I understand, either

(a) your maf is mis-reading the airflow 10% low - vacuum leaks adding air, turbulent airflow into the sensor, vibration, old maf sensor, dirty maf sensor (oiled filter ...) or

(b) your fuel system is delivering 10% less fuel than requested - dirty injectors.

again, the 10% is within Porsche spec, so looks all good (although you might need a few more miles to get the ltft to settle down).

dunno much about idle, other than, if it is idling ok, then I wouldn't worry about it.

[The Radium King]

did a bit of searching for you and the rkat is high. did you reset the ecu? otherwise perhaps check for air leak. a small leak has more effect at idle than it does at part or full throttle.

[KRAM36]

Originally Posted by The Radium King

did a bit of searching for you and the rkat is high. did you reset the ecu? otherwise perhaps check for air leak. a small leak has more effect at idle than it does at part or full throttle.

Does disconnecting the battery reset the ecu or do I have to do that with the Durametric? The car set for around 5 days with the battery disconnected.

[JAAY]

14.6:1 is normal for cruise and idle. That number bounces around a bit but is fine. I use an aem uego wideband gauge and sensor to tune up my car along with a piggybacked air flow manipulator. I use an old apexi afc select. I believe any newer one would also work. I dont have logging software but just do it the old school way. Either on a dyno or a good old stretch of road and 4th gear.

[KRAM36]

Originally Posted by JAAY

14.6:1 is normal for cruise and idle. That number bounces around a bit but is fine. I use an aem uego wideband gauge and sensor to tune up my car along with a piggybacked air flow manipulator. I use an old apexi afc select. I believe any newer one would also work. I dont have logging software but just do it the old school way. Either on a dyno or a good old stretch of road and 4th gear.

I read your thread on this, pretty slick.

So there is no way for me to get the AFR at WOT, except to change the O2 Sensors (not sure if I'm correct on that) or take it to a dyno?

[The Radium King]

not change - add - a wideband o2 sensor. it's pretty standard tuner kit - sends signal to an afr gauge, datalogger, etc. typically use bosch units so threads are universal - check you exhaust for a spare bung (preferably before the cat). if not a permanent install you could probably just install in place of a post-cat o2 sensor and put up with an emissions code for a while. plx devices also make a unit that has a narrow band output so that you should be able to install in place of an oem 02 sensor.

this will give you wot afrs. however, if your trims aren't too out of whack when running closed loop then it is a safe assumption that you're ok open loop.

[WillH]

Not to high jack but is there a "power commander V" with wideband sensors and auto tune style piggy back for the ECU that is available? I see we don't have a TuneECU freeware or of the like for the home tuner.

[KRAM36]

Originally Posted by The Radium King

not change - add - a wideband o2 sensor. it's pretty standard tuner kit - sends signal to an afr gauge, datalogger, etc. typically use bosch units so threads are universal - check you exhaust for a spare bung (preferably before the cat). if not a permanent install you could probably just install in place of a post-cat o2 sensor and put up with an emissions code for a while. plx devices also make a unit that has a narrow band output so that you should be able to install in place of an oem 02 sensor.

this will give you wot afrs. however, if your trims aren't too out of whack when running closed loop then it is a safe assumption that you're ok open loop.

Very nice, thank you.

Originally Posted by The Radium King

did a bit of searching for you and the rkat is high. did you reset the ecu? otherwise perhaps check for air leak. a small leak has more effect at idle than it does at part or full throttle.

I did a vacuum leak test today. I did a very thorough check and the only place I would get a stumble at idle was at this port valve circled in red. Had my daughter run the engine up to 2k RPM and no stumble at that port valve.

[KRAM36]

I also rechecked the KRAT numbers, they have changed, but still way off. Possible the Porsche Fualt Code 45 Cat Conv. Efficiency Bank 2 could be causing this high number on bank 2?