Not sure if anyone has any idea here..
Thinking of finally getting this thing tuned right, and dumping the flash, I have another ECU somewhere around here, from the same year 5spd eco sunfire.
Has anyone gone from the reflash back to the stock ecu tuned by HPT?
Is it possible to retain the TMAP, or do I need to reverse the wiring and sensors I did?
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ExESIVEFIRE wrote:Not sure if anyone has any idea here..
Thinking of finally getting this thing tuned right, and dumping the flash, I have another ECU somewhere around here, from the same year 5spd eco sunfire.
Has anyone gone from the reflash back to the stock ecu tuned by HPT?
Is it possible to retain the TMAP, or do I need to reverse the wiring and sensors I did?
Yes it is.... I tuned Jeff Busan's (JUCNBST) with a fake 2,5 bar tune like this. He is able to swap between the PCMs if wants(doubt he ever would though!)
P&P Tuning
420.5whp / 359.8wtq
lol talk to the man who already responded..... he will lead you down the correct path
I hear Ryan comes to Dayton now and then.
Running the TMAP setup and HPtuners for over a year. works great.
Just get a spare ecm like you said already and go to town.
13.3 @ 106 mph Cammed
Not to thread jack but thanks to QWK LN2,For all his advice for tuning with Hp Tuners...All the paper work you sent me I handed to the tuning shop and they were able to do the whole job with no issues...So Thanks for having a great member like this on the board..
So would I incorporate the IAT sensor into the tmap? Anyone explain how to do this? I plan on switchin to this sensor but need to figure out how to read IAT's with it on a t/c'd eco. Also, part #s?
"Vroom."
"Yo I wouldn't race him, there's not even an interior in his car man."
"Vrooooooom PSSSSHHH!"
"Oh sh*t. F*ck that, dude..."
So would I incorporate the IAT sensor into the tmap? Anyone explain how to do this? I plan on switchin to this sensor but need to figure out how to read IAT's with it on a t/c'd eco. Also, part #s?
"Vroom."
"Yo I wouldn't race him, there's not even an interior in his car man."
"Vrooooooom PSSSSHHH!"
"Oh sh*t. F*ck that, dude..."
Question...if using the TMAP with the stock ECU (I presume in place of the stock one-bar MAP), how does it actually understand manifold pressure on the stock Alpha-N programming?
Bill Hahn Jr.
Hahn RaceCraft
World's Quickest and Fastest Street J-Bodies
Turbocharging GM FWD's since 1988
www.turbosystem.com
I boost, therefore I am wrote:Question...if using the TMAP with the stock ECU (I presume in place of the stock one-bar MAP), how does it actually understand manifold pressure on the stock Alpha-N programming?
Fueling would still be Alpha N, with the exception of idle. The main benefit to doing this is control of timing. It will also contol IPW vs VAC modifier. Just gotta do the math and hand blend....
P&P Tuning
420.5whp / 359.8wtq
But what about the lack of proportional boost fueling? I find that to be rather alarming...it would have the same amount of injector pulse width at 2 PSI boost as it does at 10 PSI, would it not?
As the stock timing tables are proven to be very boost-friendly at up to 10 PSI on 93 octane, I'd think this woudl be an unacceptable compromise to just gain timing control.
Bill Hahn Jr.
Hahn RaceCraft
World's Quickest and Fastest Street J-Bodies
Turbocharging GM FWD's since 1988
www.turbosystem.com
DOnt question Ryan. He knows what he is doing on tuning a Jbody ECU more than I think anymone on this forum.
FU Tuning
I boost, therefore I am wrote:But what about the lack of proportional boost fueling? I find that to be rather alarming...it would have the same amount of injector pulse width at 2 PSI boost as it does at 10 PSI, would it not?
As the stock timing tables are proven to be very boost-friendly at up to 10 PSI on 93 octane, I'd think this woudl be an unacceptable compromise to just gain timing control.
Not sure about all that.... Let me ask, when was the last time you drove a car with 2psi? Jbody owners are WOT all the way if in boost! And also, you do have "somewhat" of proprotional boost fueling. As stated above, this will affect the IPW vs VAC or KPA (which is controlled by MAP) also. As long as you know how to properly scale everything, it works like a charm! Done many like this. JCNBST loves his! GM shafted us with the PCM and its sh!tty coding... Gotta use what ya got!
P&P Tuning
420.5whp / 359.8wtq
This is why we want to wire in the LD9 pcm and use the speed density reflash Bill. The lack of map proportional fueling is a bit of a pain but with a roots blower its not too big of a deal, it just makes it harder to tune. The turbo guys have a much harder time since they can realistically see major differences in boost at certain rpm/tps points.
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QWK LN2 (needs an @ss whoopin) wrote:I boost, therefore I am wrote:But what about the lack of proportional boost fueling? I find that to be rather alarming...it would have the same amount of injector pulse width at 2 PSI boost as it does at 10 PSI, would it not?
As the stock timing tables are proven to be very boost-friendly at up to 10 PSI on 93 octane, I'd think this woudl be an unacceptable compromise to just gain timing control.
Not sure about all that.... Let me ask, when was the last time you drove a car with 2psi? Jbody owners are WOT all the way if in boost! And also, you do have "somewhat" of proprotional boost fueling. As stated above, this will affect the IPW vs VAC or KPA (which is controlled by MAP) also. As long as you know how to properly scale everything, it works like a charm! Done many like this. JCNBST loves his! GM shafted us with the PCM and its sh!tty coding... Gotta use what ya got!
Well, let's just say it becomes a matter of accepting less-than stellar results. Frankly, every time I drive my turbo car, it's at 2 PSI. Also 3 PSI, 4 PSI, 5 PSI, 6 PSI....6.43 PSI, 10 PSI etc etc. You get the picture! Turbochargers present a nearly unlimited potential of part-load manifold pressure conditions that constantly occur in real-world street driving. If the car is tuned only for correct AFR at full boost, it will suffer from differing degrees of over-rich at every other boost level. It will be finicky, experience poor fuel mileage, and eat spark plugs like candy. Some may find this acceptable...I surely do not.
Leafy wrote:This is why we want to wire in the LD9 pcm and use the speed density reflash Bill. The lack of map proportional fueling is a bit of a pain but with a roots blower its not too big of a deal, it just makes it harder to tune. The turbo guys have a much harder time since they can realistically see major differences in boost at certain rpm/tps points.
You nailed it. For turbo cars, HPT alone is a significant compromise on Alpha N. For the blower cars, this lack of proportional fueling is much less of a concern, but it's still going to lead to chunky behaviors at certain load points.
Bill Hahn Jr.
Hahn RaceCraft
World's Quickest and Fastest Street J-Bodies
Turbocharging GM FWD's since 1988
www.turbosystem.com
I boost, therefore I am wrote:QWK LN2 (needs an @ss whoopin) wrote:I boost, therefore I am wrote:But what about the lack of proportional boost fueling? I find that to be rather alarming...it would have the same amount of injector pulse width at 2 PSI boost as it does at 10 PSI, would it not?
As the stock timing tables are proven to be very boost-friendly at up to 10 PSI on 93 octane, I'd think this woudl be an unacceptable compromise to just gain timing control.
Not sure about all that.... Let me ask, when was the last time you drove a car with 2psi? Jbody owners are WOT all the way if in boost! And also, you do have "somewhat" of proprotional boost fueling. As stated above, this will affect the IPW vs VAC or KPA (which is controlled by MAP) also. As long as you know how to properly scale everything, it works like a charm! Done many like this. JCNBST loves his! GM shafted us with the PCM and its sh!tty coding... Gotta use what ya got!
Well, let's just say it becomes a matter of accepting less-than stellar results. Frankly, every time I drive my turbo car, it's at 2 PSI. Also 3 PSI, 4 PSI, 5 PSI, 6 PSI....6.43 PSI, 10 PSI etc etc. You get the picture! Turbochargers present a nearly unlimited potential of part-load manifold pressure conditions that constantly occur in real-world street driving. If the car is tuned only for correct AFR at full boost, it will suffer from differing degrees of over-rich at every other boost level. It will be finicky, experience poor fuel mileage, and eat spark plugs like candy. Some may find this acceptable...I surely do not.
Who said anything about not tuning driveablity? Matter of fact, thats the first thing that should be tuned in book! Part throttle boost would be included in this.... This is "real world" driving. Its not like we are just fudging numbers on a more complex PCM (such as an E67) and only modifying flow rate values and leaving the offset voltages, and other inportant parameters and scaling alone....
P&P Tuning
420.5whp / 359.8wtq
alright, I'm going to chime in here as far as using the tmap on a stock htp tuned ecm....it works fine. I have no difference in mpg's around town and I gained a few on the highway. Bill- as far as being overly rich and eating plugs, I've had no issue, the only time I'm in boost is when I'm wot, otherwise I'm in vac so I got no complaints. I will say that I would advise against using an aluminum flywheel, as the car stalled out a few times at random after the tune, but I switched back to my stock flywheel and all is good. If you have any questions let me know I've been driving the car daily since the tune in May and have about 9-12k on the car since then.
All I know is anything has to be better than this @!#$ty reflash...
like seriously the car acts like a dog unless were in the top 1500 rpm of my gear...
forget cruising and nailing the throttle, it falls on its fawking face every time.
** FOR SALE**
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QWK LN2 (needs an @ss whoopin) wrote:I boost, therefore I am wrote:QWK LN2 (needs an @ss whoopin) wrote:I boost, therefore I am wrote:But what about the lack of proportional boost fueling? I find that to be rather alarming...it would have the same amount of injector pulse width at 2 PSI boost as it does at 10 PSI, would it not?
As the stock timing tables are proven to be very boost-friendly at up to 10 PSI on 93 octane, I'd think this woudl be an unacceptable compromise to just gain timing control.
Not sure about all that.... Let me ask, when was the last time you drove a car with 2psi? Jbody owners are WOT all the way if in boost! And also, you do have "somewhat" of proprotional boost fueling. As stated above, this will affect the IPW vs VAC or KPA (which is controlled by MAP) also. As long as you know how to properly scale everything, it works like a charm! Done many like this. JCNBST loves his! GM shafted us with the PCM and its sh!tty coding... Gotta use what ya got!
Well, let's just say it becomes a matter of accepting less-than stellar results. Frankly, every time I drive my turbo car, it's at 2 PSI. Also 3 PSI, 4 PSI, 5 PSI, 6 PSI....6.43 PSI, 10 PSI etc etc. You get the picture! Turbochargers present a nearly unlimited potential of part-load manifold pressure conditions that constantly occur in real-world street driving. If the car is tuned only for correct AFR at full boost, it will suffer from differing degrees of over-rich at every other boost level. It will be finicky, experience poor fuel mileage, and eat spark plugs like candy. Some may find this acceptable...I surely do not.
Who said anything about not tuning driveablity? Matter of fact, thats the first thing that should be tuned in book! Part throttle boost would be included in this.... This is "real world" driving. Its not like we are just fudging numbers on a more complex PCM (such as an E67) and only modifying flow rate values and leaving the offset voltages, and other inportant parameters and scaling alone....
If you've made it work in a fashion where folks just need to only go after boost at WOT, and not at part throttle, I can see where it could suffice when driven accordingly. However, I'll admit I do not know all the details of this "fake 2.5 bar" approach. But nonetheless, there's a significant difference in airflow and subsequent fueling at, say, 1 PSI boost and 10 PSI...about 70% difference. That's a world apart to have to support with exactly the same fuel delivered to the engine at all boost levels. Does this "fake 2.5 bar" somehow address this, and if so, how?
To all: the E67 PCM (in Cobalt, HHR, and others) is a great example. It can be tuned to accomodate boost rather nicely on airflow only, for it can readily compensate for this 70% difference using measured MAF airflow. Even without a TMAP (it features a stock one-bar MAP), it performs this purpose very well, and very repeatably, as it should...GM's strategy for boosted cars is to use MAF for the primary fuel calculation, with the TMAP sensor only there as a backup should the MAF fail. The Ford vehicles we add turbocharging to also achieve proportional boosted fueling via MAF exclusively.
Needless to say, the GMPP supercharged TMAP tune for J-body is pure speed-density, for there is no MAF. But even in this case, scaled proportional fueling is achieved, as it is in any OEM-engineered forced induction system.
Now, this is not the "sales pitch" part of my participation in this thread, but it bears saying: We've provided PortFueler systems to a number of turbo J-bodies who were dissatisfied with this non-proportional boost fueling shortcoming of the pure HPT approach, the most notable one being Camron Fredrick and his 10-second Cavalier. While Camron's car only sees limited street use now, he prizes its much improved behavior at all boost levels since switching to a true boost-proportional fueling solution. Now, to be fair, I do not know if these dissatisfied folks were using this "fake 2.5 bar" approach, or if, like Camron, were just trying to hack it with the stock PCM and MAP.
Edited 1 time(s). Last edited Wednesday, October 13, 2010 6:25 PM
Bill Hahn Jr.
Hahn RaceCraft
World's Quickest and Fastest Street J-Bodies
Turbocharging GM FWD's since 1988
www.turbosystem.com
