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  #31  
Old July 1st, 2017, 02:02
RCP Phx RCP Phx is offline
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Re: 4.6 build starts today!!!

I've got 12 miles on it so far. Fired it back up and let it idle for a few minutes, it settled right in to a smooth idle. Even though it was only 110* out today the temp stayed right at 210*. Got 12 miles on it and it runs like a "raped ape", had a hard time holding it back. Will do a oil change this morning and hit it even harder after that! Even at 9.4CR and regular pump gas I saw no signs that would be a problem. Put my older Innova scanner on it to record some data. I had the muffler shop add a 3rd bung for my A/F meter and will do some logging of that later!
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  #32  
Old July 4th, 2017, 11:49
RCP Phx RCP Phx is offline
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Weekend update!

Well the first thing done was to remove the Brown Dog mounts, hated them!
Been driving around taking scanner readings and waiting for a full state of "Readyness" on the scanner. I finally hit 100 miles and all is "ready".

The next step has me "lost" since I'm old school and don't understand what all the data really means to me and where to go from here. I have sent ChrisTuner a e-mail to see if he can help. I would love to actually see what's going on in real time.

Other than that it seems to be running great!

It seems to be using fuel like crazy but I haven't checked a plug yet since that's not easy!

Last edited by RCP Phx; July 4th, 2017 at 11:59.
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  #33  
Old July 5th, 2017, 04:54
Redsnake Redsnake is offline
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Re: Weekend update!

Quote:
Originally Posted by RCP Phx View Post
Well the first thing done was to remove the Brown Dog mounts, hated them!
........................
What motor mounts did you end up using? I've been running the Brown Dog mounts on my 01 XJ for a couple years and I've yet to ever get used to the increased NHV that they created. I like that my engine stays put and my fan doesn't eat up my Aluminum radiator... but I'd like it better if it didn't make my rig shake like an '84 Camaro... :\
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  #34  
Old July 5th, 2017, 10:48
RCP Phx RCP Phx is offline
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Re: Weekend update!

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Originally Posted by Redsnake View Post
What motor mounts did you end up using? I've been running the Brown Dog mounts on my 01 XJ for a couple years and I've yet to ever get used to the increased NHV that they created. I like that my engine stays put and my fan doesn't eat up my Aluminum radiator... but I'd like it better if it didn't make my rig shake like an '84 Camaro... :\
I put my 17yr old set back in! They looked and worked fine. I'm trying to devote all my time to fuel management right now!
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  #35  
Old July 5th, 2017, 12:54
RCP Phx RCP Phx is offline
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Re: 4.6 build starts today!!!

I'll try to post some "frameshots" later under different load conditions, but as I got it warmed up today it was reading "LTFT 24.2%"
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  #36  
Old July 6th, 2017, 10:39
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cal cal is offline
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Re: Weekend update!

Quote:
Originally Posted by Redsnake View Post
What motor mounts did you end up using? I've been running the Brown Dog mounts on my 01 XJ for a couple years and I've yet to ever get used to the increased NHV that they created. I like that my engine stays put and my fan doesn't eat up my Aluminum radiator... but I'd like it better if it didn't make my rig shake like an '84 Camaro... :\
http://www.stinkyfab.com/heavy-duty-...-comanche.html

Stinkyfab had their own bushings poured out of the softest material that will hold up. Very comparable to stock on the durometer. Slightly more vibe than an OEM bushing but WAY better than the competition, or even his older mounts using off the shelf bushings.
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  #37  
Old July 6th, 2017, 10:53
Redsnake Redsnake is offline
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Re: Weekend update!

Quote:
Originally Posted by cal View Post
http://www.stinkyfab.com/heavy-duty-...-comanche.html

Stinkyfab had their own bushings poured out of the softest material that will hold up. Very comparable to stock on the durometer. Slightly more vibe than an OEM bushing but WAY better than the competition, or even his older mounts using off the shelf bushings.
Interesting!! So these should give less NHV than the Brown Dog Rubber mounts I'm currently running? Do you have any personal experience w/them? I'll have to look into this a bit more as I love the 'idea' behind heavy duty Motor Mounts like the ones Brown Dog makes, but I seriously HATE the increased NHV they all seem to produce on our XJ's. I fix one area that is vibrating like a paint shaker only to have something else start up a few weeks later. :\

Sorry to thread jack...
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  #38  
Old July 6th, 2017, 10:57
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Re: 4.6 build starts today!!!

I've driven on them, more NVH than stock mounts but less than brown dog rubber or SFR's old poly mounts.

As far as how much more or less, its hard to say, as I have not made the change in the same jeep so its not really apples to apples.
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  #39  
Old July 7th, 2017, 12:57
RCP Phx RCP Phx is offline
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Re: 4.6 build starts today!!!

Well I've got over 200 miles on it so far. I took to emissions yesterday since my plates were due at the end of June. I didn't see the build taking 8 weeks!
I've got set of 27lb injectors ordered to see if I can get the fuel trims closer to their mid-range. Still haven't heard from Chris Jensen on custom tuning?
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  #40  
Old July 7th, 2017, 13:21
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1990JEEPXJ 1990JEEPXJ is offline
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Re: 4.6 build starts today!!!

Did it not pass smog?
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  #41  
Old July 7th, 2017, 14:25
RCP Phx RCP Phx is offline
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Re: 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"!
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  #42  
Old July 8th, 2017, 14:30
RCP Phx RCP Phx is offline
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Re: 4.6 build starts today!!!

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.
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  #43  
Old July 8th, 2017, 19:13
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Re: 4.6 build starts today!!!

Contact Ryan Hogan too. he did all of my tuning. Great Guy and really dialed in the stroker.
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  #44  
Old July 9th, 2017, 10:29
hexdmy hexdmy is offline
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Re: 4.6 build starts today!!!

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.
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  #45  
Old July 9th, 2017, 11:56
RCP Phx RCP Phx is offline
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Re: 4.6 build starts today!!!

Quote:
Originally Posted by hexdmy View Post
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?
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