Tuning Gurus: help please

[Redog]

I posted over on HP tuners as well, but I'm still new at this and getting lost pretty easy.

My custom PCM which was tuned by an old member on here from Colorado, is my baseline for this tune. I still have my DHP PCM and my stock PCM.

Fuel: put in trailblazer 28 lb injectors. The orginal program was 21.31 across the board under the MAP screen. I uped that to 27.31 across the board. Redog can lay wheels now upto about 35 MPH on a slick street I couldn't find the IFR chart. I calcuated that I need to chage my injector rate (or something liek that) to 78.6% becuase my injectors are 21.4% larger now.

No idea on MAF tuning. Any insight?

Transmission: raised shift points 10% and feel nothing, don't know if I used the correct program. Don't worry I saved the orginal chart I messed with

Also the 1>2 shift point was 6600 RPMs I lowered it many times but it would still shift at 6600 RPMs. A guy on HPtuners.com said I have to change the MPH shift point too. It was at 47 MPH, it's now at 39 and the shift point is at 5750. Car shifts at 6200 RPM's now. It's not redline, but I still want that down to 5900 or 6000.

Fixed all the easy stuff. Fan on and off temp at temps 1 and 2. Idle speed in P/N in gear and with the A/C on and the fans are on for 180 seconds after key off Also bye bye pesky P0440 code (AIR Injection system code)

Any ideas on the programs? Basicly bolt ons on the car. Heads are milled bringin CR to about 9.7:1. P&P manis, Headers, 180* thremo, 28 lb injectors, intake and full exhaust. Looking for a LS1 MAF soon

[AleroB888]

I'm not a guru, but I have my have my 28 lb injectors set at 25, and my fuel trims are now just right for this temperature and altitude. Also using a stock LS1 MAF table.

[Redog]

Where is the stock LS1 MAF table? is that on the HP tuner's web site?

[AleroB888]

Originally Posted by Redog

Where is the stock LS1 MAF table? is that on the HP tuner's web site?

The one I use was listed as a "1997 Corvette LS1", and one of the GrandAmGT.com guys got it from the HPTuners site. That's been a few years, though. There was a way you could copy and paste it out of a regular forum post, but it was tricky, IIRC.

[BlackJack]

whoa, before you get into LS1 MAF tables, you ARE using an actual LS1 MAF yes? LOL

Ok, so basically the formula for calculating for different size injectors are (original size) / (new size) = percent difference.

Then take the IFR and (original IFR) * (percent difference) = new IFR.

So, if you had 18# injectors and went up to 28# injectors, it would look like this:

18/28 = .643
and then for your IFR,
21.4 * .643 = 13.76
and there you would have your new IFR under the MAP tables.

Now that you have your new starting IFR, I recommend you do a full VE tune before continuing. Start with your PE set to 0 all the way down, disconnect your MAF sensor and get your tune on after you reset and relearn the trims. Scan and make your adjustments. Ensure all your trims are at a slight negative (-) because you don't want an induced lean condition. Once you have your VE dialed in and reprogrammed, then reconnect your MAF, set your PE back to where you like it, and then start your MAF tune.

Now, as for your shift points, during WOT shifts (actually above 99.6% TPS), the computer uses RPM. For less than WOT, it uses MPH.

Hope this helps. Good luck buddy

[Redog]

No I don't have a LS1 MAF yet, I wanted to get the other stuff working first.

The stock injectors are 18? I thought they were 22? Will I be OK setting that at 27.31 on the MAP side?

I've seen the VE, I've seen the PE, but I did not go into them yet because I did not know what they are. What are they? I also have not seen the IFR tables or where I would put in that 13.76 in at. Also is that 13.76 a %? so putting it in I would just highlite the entire chart and mutiply by 1.1376?

How do I get more pressure at the shift solidon (sp) I don't want to go high enough to break my neck, but I want it stiff enough to feel it when I shift and not lose much RPM on a WOT, like at the track. It'd be sweet to keep the shift points at WOT right in the power range (4000 RPM's)

Although I have DHP and not HPT, I have been tweaking my tune with Ben's help.

I have Trailblazer injectors also, and use a factory-stock FPR.

I sent him my bin file, and my Injector flow rate was way off. Now, DHP uses mSec/Gram for the fuel injector measurement, so it's a bit of a different calculation. But I went from 340.15 mSec/Gram to 300.97 mSec/Gram and my fuel trims are damn-near spot-on (FYI, stock setting was 371 mSec/Gram). And if you are using a stock MAF, you should use the stock MAF table. My MAF and VE tables are factory-stock right now.
That said, 2000+ cars allegedly got 22.5#/hr injectors, and that is measured at 55psi. The Trailblazer injectors are 28#/hr, but that is measured at 62psi, so you have to adjust if you are running a stock FPR @ 55psi.
At 55psi, Trailblazer injectors flow 26.37#/hr.
Good luck!

[BlackJack]

Originally Posted by Redog

No I don't have a LS1 MAF yet, I wanted to get the other stuff working first.

The stock injectors are 18? I thought they were 22? Will I be OK setting that at 27.31 on the MAP side?

I've seen the VE, I've seen the PE, but I did not go into them yet because I did not know what they are. What are they? I also have not seen the IFR tables or where I would put in that 13.76 in at. Also is that 13.76 a %? so putting it in I would just highlite the entire chart and mutiply by 1.1376?

How do I get more pressure at the shift solidon (sp) I don't want to go high enough to break my neck, but I want it stiff enough to feel it when I shift and not lose much RPM on a WOT, like at the track. It'd be sweet to keep the shift points at WOT right in the power range (4000 RPM's)

ah jeez....here we go. I'm going to have to start with the disclaimers. I said IF YOU HAD18# injectors. Meaning, as an example. Do not plug any of the numbers I gave you up there. Those are calculations based on a theoretical situation simply to display the METHOD of how to get those numbers. And Matt is right. Fuel pressure comes into play here.

Next, VE and PE.
VE is Volumetric Efficiency by definition is how effectively the engine can move airflow. Now, as it applies to your tables in the tune, these are numerical values that tell it how much fuel to spray based on RPM vs. MAP. These will be your base level fuel numbers, and the computer will use these to make all the other calculations (it will decide to add more or less fuel to this base value on things such as air flow and temperature). The reason you want your VE dialed in is for two reasons. If your MAF ever fails, your fueling will still be "close" to where it should be without calculating for air flow, and less chance of blowing your engine due to excessive lean or rich conditions as a result, and two, your computer has to make less fueling adjustments based on other sensor input (fuel trims will be lower).

Example: Your engine is at say (theoretical numbers here, not actual) 4500RPM and your MAP reads 60kPa and the value for that cell would be around 66%. Your computer will use that as a base, and add a little more or a little less based on your MAF and your O2 readings, along with variances in temp etc.

Last, PE. This is basically an adjustment used for getting the desired A/F ratio when under load. You want to do your VE tune without the use of PE so that it doesn't "add" fuel based on your level of acceleration and load and skew your fuel numbers while you're trying to scan for your base VE tables. After you get your VE set right, you can put your PE numbers back in.

For the rest of the stuff like transmission etc., you're going to have to develop a feel for transmission settings based on your car's setup, such as powerband, gear ratios, tire diameters, etc. I will tell you this though, making wrong adjustments in torque management can end a transmission, so please read up carefully from some of the "published experts".

Here's a link for lots of "how-to" all in one linked post if you're a registered DHP PowrTuner owner and have access to the forum there:

http://www.powrtuner.com/index.php?showtopic=6735

Another reason to get your VE table in line (in layman's terms).....
At WOT, the computer relies on MAP values (and engine speed) rather than MAF sensor input.
That means, at WOT your computer basically resorts to your VE table and MAP values (and PE adjustments, natch). So if the VE table values are way off, and the computer has to make a bunch of adjustments, you will never run as strong at WOT as you could.

[Cliff8928]

Originally Posted by Redog

The stock injectors are 18? I thought they were 22?

and....

Originally Posted by WOT-TECH

The 00+ injectors are 21.31# at 55psi

Originally Posted by Redog

How do I get more pressure at the shift solidon (sp) I don't want to go high enough to break my neck, but I want it stiff enough to feel it when I shift and not lose much RPM on a WOT, like at the track. It'd be sweet to keep the shift points at WOT right in the power range (4000 RPM's)

Lower the values of the Force Motor Current, increase shift pressure, decrease shift time. Those are the 3 settings you have regarding shift quality.

[Redog]

OK That's for all the help, but I want to fix something else, more important, first

I can't change the VIN in my car. The PCM I put in was from a 2001 Alero and I think that is why my P0135 code (O2 heater circut) is comming on. It didn't come on before the PCM swap and now it's on so I want to see if this is the problem BEFORE I buy a new O2 sensor.

I go to "change VIN" and the wrong one pops up and I type in mine and I get "Invalid VIN and OS"

I did a full read, write calibration, and it still won't work. All the error message has is a "close" button. Also the gauge screen doesn't work when the motor's running.

What do I do?

[Cliff8928]

The gauge screen you have to connect and then start scanning (looks like a play button if I remember right).

You can't change the VIN because the OS is incorrect. Also, with a VIN change, you will have to re-license the new VIN.

The OS version on the 2001 PCM most likely is not correct for your 2000 because of the changes from 00 to 01. It knows this and won't let you do it.

[Redog]

So what do I do about the VIN?

Is this why I'm getting a heater circut malfunction on the upstream O2? Or is the O2 ensor actually bad?

[Cliff8928]

To change the VIN to your VIN, you would need to have a PCM with the correct OS on it. So basically that means either getting a different PCM or having that one flashed with a Tech2.

As for the upstream, I doubt they changed the wire locations. The sensor might actually be bad.

[Redog]

OK, Ill look around for the PCM.

Just checking on the O2 sensor. It was just odd that it when out right after I put in the new PCM

[sleepyalero]

my buddy has a LS1 Trans Am and my car has the same MAF as his does, and i have never changed it.

[lvemy3100]

Originally Posted by Redog

So what do I do about the VIN?

Is this why I'm getting a heater circut malfunction on the upstream O2? Or is the O2 ensor actually bad?

If you pay for shipping to me and back to you I will change the vin to whatever you want

as for the o2 sensor I could not say anything about that for sure.. could be bad o2, bad wiring, bad connector...

[Redog]

I trimed the VE, left the PE alone (put at 0 to get a reading) and changed the IFR to 26.27.

The VE I changed everything 1.2% except for the bottom left corner, which was all at 91 stock. That I cahnged 1.1% One block was at 106, but I put it back to 105. I did not want the MAP to be higher than 105.

I'm going to leave the PE at stock.

I smell the car running rich now. I didn't touch the MAF Delta postive and Delta Negitive where both at 66.71 stock, but the max says 67.7 accroding to the HP tuners.

I'm guessing it's working. The car feels much slower, but it running richer, a lot richer. I'm going to pick up a 1997 Corvette LS1 MAF tomorrow and find that chart that Alero B888 was talking about.

Sound good?

I want to get this fixed first, then I'll worry about the trans program

[Redog]

Originally Posted by Redog

Is this why I'm getting a heater circut malfunction on the upstream O2? Or is the O2 ensor actually bad?

This went away, hasn't come back

[AleroB888]

Originally Posted by Redog

......... I'm going to pick up a 1997 Corvette LS1 MAF tomorrow and find that chart that Alero B888 was talking about.
...........................

If you hit the "quote" button under the post (as if to reply to the post), then copy the table out from between the quote tags, you can paste it into the HP tuners MAF table. ............worked for me....

http://www.grandamgt.com/forum/showthread.php?t=72597&highlight=LS1+MAF+table&pag e=2