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4.6 build starts today!!!

It did pass, but trying to move forward (on my own) in the mean time! I figure "if I can't tune my computer to my engine, I'll try and tune my engine to the computer"!
 
Well Chris e-mailed me today, so hopefully we can start a BC there! Anyway with my education I learned today that it does display "open and closed" loop so I learned something again. The question now will be how the new injectors respond since I really didn't know much about the ones I installed last year to base a call on.
 
Contact Ryan Hogan too. he did all of my tuning. Great Guy and really dialed in the stroker.
 
Just a couple of comments, and I understand that many know these points already, but I just thought I would chime in based on my experiences tuning these motors.

Fuel tuning:

Strokers need bigger injectors, roughly in proportion to the increase in displacement. I typically recommend 27 lb/hr injectors, but then again, there are many choices in the 24-27 lb/hr injector range, and typically 24# injector brand X will not flow the same as 24# injector brand Z. Sounds somewhat trivial, but this makes it difficult to predict fueling needs given a specific build based on previous tuning experience. In general, I've seen a wide range of fueling requirements on what I would consider are very similar builds.

Don't assume that the fueling is close based on how the Jeep drives or looking at the fuel trims. The JTEC engine controller has a range of authority of +/- 33% for short term and long term fuel trims which means a total range of +/- 66% . The long term fuel trims in most calibrations are only applied to closed loop operation, however in some (not many) calibrations one of the long term fuel trim cells is applied to open loop fueling in the positive direction. Also, there are 153 fuel cells in your main fuel lookup table, while there are only about 22 long term fuel trim cells, so the long term fuel trims are very "choppy" compared to the actual fuel look-ups. What this means is that your tune can be quite a bit off, and the ecu will learn the fueling to some degree, the short term fuel trims will keep the engine running around lambda 1 in closed loop, but typically this will not help you at high engine loads while in open loop.

Regarding evaluating the air fuel ratio, looking at a air fuel ratio gauge while driving the Jeep will not help us much as far as tuning goes. It is better than doing nothing, and will certainly give us an idea if we are grossly rich or lean, but the engine is mapped in rpm and map cells, and logging provides a way to accurately evaluate the air fuel ratio through most of these fuel map cells.

The SCI data stream is capable of 500 bytes per second update rate, however not so with the generic OBD2 data stream which is what SCT and other scan tools typically use. Since there is not a readily available and reasonably priced tool that can log the factory SCI data stream, the next best thing is parallel logging the signals being fed into the JTEC, and this is what I recommend. Using the generic OBD2 data stream, you will typically see about one to four updates per second, polling three or four PIDS, that is not very useful. Alternately using a Zeitronix ZT-2 logger as an example, you will receive about forty updates per second for each channel logged. By tapping into three wires of the JTEC, map signal, cam position signal, tps signal, you will have a high resolution logging solution. To measure the air fuel ratio error, we need to eliminate the factory fuel trims. Unplugging the stock O2 sensors will prevent the JTEC from going into closed loop. Disconnecting the battery power from the JTEC for at least a minute will clear any fuel trims. Once those two things are done, measured air fuel ratio will be a result of base fuel pulse width calculation without any influence of fuel trims.
 
Just a couple of comments, and I understand that many know these points already, but I just thought I would chime in based on my experiences tuning these motors.

Fuel tuning:

Strokers need bigger injectors, roughly in proportion to the increase in displacement. I typically recommend 27 lb/hr injectors, but then again, there are many choices in the 24-27 lb/hr injector range, and typically 24# injector brand X will not flow the same as 24# injector brand Z. Sounds somewhat trivial, but this makes it difficult to predict fueling needs given a specific build based on previous tuning experience. In general, I've seen a wide range of fueling requirements on what I would consider are very similar builds.

Don't assume that the fueling is close based on how the Jeep drives or looking at the fuel trims. The JTEC engine controller has a range of authority of +/- 33% for short term and long term fuel trims which means a total range of +/- 66% . The long term fuel trims in most calibrations are only applied to closed loop operation, however in some (not many) calibrations one of the long term fuel trim cells is applied to open loop fueling in the positive direction. Also, there are 153 fuel cells in your main fuel lookup table, while there are only about 22 long term fuel trim cells, so the long term fuel trims are very "choppy" compared to the actual fuel look-ups. What this means is that your tune can be quite a bit off, and the ecu will learn the fueling to some degree, the short term fuel trims will keep the engine running around lambda 1 in closed loop, but typically this will not help you at high engine loads while in open loop.

Regarding evaluating the air fuel ratio, looking at a air fuel ratio gauge while driving the Jeep will not help us much as far as tuning goes. It is better than doing nothing, and will certainly give us an idea if we are grossly rich or lean, but the engine is mapped in rpm and map cells, and logging provides a way to accurately evaluate the air fuel ratio through most of these fuel map cells.

The SCI data stream is capable of 500 bytes per second update rate, however not so with the generic OBD2 data stream which is what SCT and other scan tools typically use. Since there is not a readily available and reasonably priced tool that can log the factory SCI data stream, the next best thing is parallel logging the signals being fed into the JTEC, and this is what I recommend. Using the generic OBD2 data stream, you will typically see about one to four updates per second, polling three or four PIDS, that is not very useful. Alternately using a Zeitronix ZT-2 logger as an example, you will receive about forty updates per second for each channel logged. By tapping into three wires of the JTEC, map signal, cam position signal, tps signal, you will have a high resolution logging solution. To measure the air fuel ratio error, we need to eliminate the factory fuel trims. Unplugging the stock O2 sensors will prevent the JTEC from going into closed loop. Disconnecting the battery power from the JTEC for at least a minute will clear any fuel trims. Once those two things are done, measured air fuel ratio will be a result of base fuel pulse width calculation without any influence of fuel trims.

Is this Chris?
 
Contact Ryan Hogan too. he did all of my tuning. Great Guy and really dialed in the stroker.

I figured Chris is closer in case I have to take it there. But I am aware of FRP!
 
I got a call from Chris Monday afternoon to go over some fine points, I told him of my current plans. Well I received my new injectors today! They are sold as 27@49 psi. The only marking is XF1E-A5B that translates to (0 280 155 849). They are engraved with "27" which I assume is the tested flow rate @ 49psi. I will try to get them in tonight with results soon after.
I should add that they are going to replace some 0 280 156 077 injectors I bought last fall that are supposed to be 24@49.
 
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I finally got the injectors installed this morning after a bit of a oil leak! I installed a PSC ps pump last Saturday that had a major leaking front seal, had to put the stocker back on. Currently the injectors seem to be what I needed, the trims are +/- 5% now and it eliminated a stumble/dead spot I was getting from a dead stop to WOT. I will spend the rest of the weekend getting some AFR runs logged to see where I'm really at!
 
I'm interested to see how the tuning works out. I currently have a stroker kit order with Russ.
 
Ok, here's what I found out this weekend! Remember I'm using old equipment, a Innova 1303 and a Innovate LM-1. My set-up will only log a max of 44min at a time, so I broke it down a little. I wished I knew of a way to post the time/bar graphs I got(there in LogWorks 3.0), I might try to take pics later!

I decided on 4 criteria........for 4 separate runs each

1- Cold start to full warm-up
2- Neighborhood driving - max 45mph
3- 0-60mph WOT
4- 0-60 Freeway cruising

Basically the numbers show excellent in all the graphs with the most consistent value at 14.5 and with high and lows(within seconds) of 15.1-13.2.
 
I received a e-mail Monday from Chris asking for me to send some of my files to him, which I did. Just received a response stating it didn't look bad but would need more info to truly see what's happening. That's where the question lies.

It would take a major investment to be able to export the current logs, spend time/money on custom files, and be able to import those files to my PCM.

So while I kick around that idea, I'm still trying to find things on my own that might need addressed.

One thing I wasn't impressed with during the build was the Cam position sensor. I found no other method than the "toothpick" trick but question the accuracy of that. What does the CPS do within the PCM and how do I tell if it's truly adjusted to where it needs to be?
 
cam position sensor sets the timing on when the injectors fire. when its out, its a full cam tooth out, and it will either run crappy at the top of the tach or at idle.

if its running smooth, you're dialed in there.
 
I know that it is indexed properly with the gears, but the "toothpick" method still allows a "little" room for error as it is not a "positive" engagement. That's why I was questioning how the PCM sees and "syncs" the crank and cam positioner, and since my cam has a built in 3* of advance. How much room for error is there?
 
To go beyond what I can do, I made a appointment(3 weeks out) with one of Phoenix's best shops to put it on the Dyno/computer(CMR based). After that evaluation I can see what else it needs(if anything) to get done! I'm not comfortable investing in everything it would take to get this done with me as a "middle" man. The other choice is to take it over to Chris(still quite a investment).
 
For your logs, is there a way for you to export/save/convert to PDF? Otherwise a 'screenshot' and a quick save should let you upload it.
 
All my logs were saved and exportable, but they are only readable thru Innova's Logworks 3.0!

On a bright note, yesterday I managed to score some Rubi rims at a deal(been looking for a couple of years)! I needed new tires so that was done today. It's so smooth now I'm looking forward to the Dyno runs!
 
Well, today was the big day and it came off perfectly! The guys at Lopers said they hadn't seen such a strong motor!

Max rear wheel horsepower = 227hp
Max rear wheel torque = 396 ft/lbs

AFR's were great with just a slight fattening under 50% dyno load and WOT.

I think I'm done now!
 
You're killing me smalls!!! Why did you have to do that? 225 hp/400 ft-lb at mid 9s CR?!?! I need new underwear. Been waiting to see a 0331 based build with dyno numbers and now we know. I think this will start a few conversations...

Question, Chris and Russ, any chance of a "package"? This build sheet, these injectors, this tune, done! Drooling...
 
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