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Discussion Starter · #1 · (Edited)
I have yet to get my SRT8, still about 6 months out but I'm trying to do all my homework prior so I know what to look for and what to go after when I finally do....

My question(s ) are directed to primarily JerseyBoy and Johan ( sp )

From past experience with doing custom tunes, it is always better for you the tuner to have the vehicle in hand while doing the tunes, for data loging, tweeking..etc.
So how do you do this otherwise ?
Do I order a tuned ecm/tcm from you and you send it to me and I send you back my stock ecm/tcm?
Or do you send it to me in a file and I hook up a lap top and down load it through the obd port ?

One small issue I had when tuning my truck with EFI LIVE was , the first one I had done , I sent out my ecm/tcm to missouri had it tuned and I put it back it..had some fuleing issues and shift/torque paramiters were acting funny and the fuel tables were way defueled. The second I drove out to Salt Lake City to have one of the best Duramax and EFI tuners in the biz tune for me..along with doing twin turbos..:D...! The truck ran like a raped ape ...out there...breaking the tires loose in 4th in a dually...sick ! When I got home to Denver..I could feel a significant change in her..still ran hard , but not like it did in SLC.
Drove back out there , had some tables tweeked on and same issue. talked to another local guy that was an original beta tester for EFI and has been working on Duramaxes since day one...all came down to elevation changes. The ECM will adapt as much as possible to the atmospheric pressure changes and lack of O2, but will only do so much.

So...my concern is , JerseyBoy, im probably 5000' higher than you and Johan..not sure of your loc....do you guys tune in accordance with the vehicles primary elevation ? Or do the ecm/tcm in the jeeps adapt better than the ecm/tcm with my truck?
Also off topic...i've seen this anogram all over this site, what is CAI ?

Again thank you all for your input and advice.
I'm sure a lot of my questions have been discussed in previous postings and I appologize in advance for the redundancy.
 

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Best to get a tune dialed in, IMO, would be to get a Diablo Trinity, along with a AFR sensor to hook up to it. That way you can datalog and send the log file to the tuner who can make the appropriate changes to the tune for your jeep.

All can be done via email.

CAI=cold air intake.
 

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Discussion Starter · #3 ·
Best to get a tune dialed in, IMO, would be to get a Diablo Trinity, along with a AFR sensor to hook up to it. That way you can datalog and send the log file to the tuner who can make the appropriate changes to the tune for your jeep.

All can be done via email.

CAI=cold air intake.
CAI....DUH...!:werd:....thanks
 

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your wideband sensor will have your actual air fuel ratio, which in a way will help tell your altitude level. your fuel trims, baro reading, and air fuel ratio with you wideband all tell the tuner what needs to be done according to your altitude. lack of 02 hurts these engine i live in durango, when i go down to phx she is a whole different animal just from the altitude change.
 

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Discussion Starter · #5 ·
your wideband sensor will have your actual air fuel ratio, which in a way will help tell your altitude level. your fuel trims, baro reading, and air fuel ratio with you wideband all tell the tuner what needs to be done according to your altitude. lack of 02 hurts these engine i live in durango, when i go down to phx she is a whole different animal just from the altitude change.
Yeah so you for sure know my pain !
We went on a huge road trip this past summer, towing a 40' 5th wheel toy hauler and boat in tandem...when we were in Vegas , I unhooked and went looking for trouble around town...JESUS..my truck was the incredible hulk on steroids...unbelievable ! Couldnt get traction..no sleeves or braces so no 4wd boosted launches.
 

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I'm not positive, but I'm pretty sure you can live tune without them @ location. You essentially drive around per their requests and send them the log. They send back a tune, you upload, rinse repeat. Then your altitude and driving style are a part of the tune. Or, you can throw it on a nearby dyno if that is easier for you.

Rarely is there ever a time ANYONE needs to be in a location to do anything, the technology we have now is incredible.
 

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From personal experience I live at 2400ft and Johan asked me what elevation I lived at because my map sensor was reading different do to the elevation which in turn caused me to see more timing than he commanded so he adjusted it for that. So yes they can adjust for it but you will still run better and different at sea level just because of the thicker air. He has it set so the map sensor reads the sameat sea level because my local tracks are about 300ft. Not sure how much ft difference the car can adjust for though in the tune.
 

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yes and the map is another to view to determine altitude. talk to johan or jersey boy, i plan to do the same when i install my headers.
 

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From personal experience I live at 2400ft and Johan asked me what elevation I lived at because my map sensor was reading different do to the elevation which in turn caused me to see more timing than he commanded so he adjusted it for that. So yes they can adjust for it but you will still run better and different at sea level just because of the thicker air. He has it set so the map sensor reads the sameat sea level because my local tracks are about 300ft. Not sure how much ft difference the car can adjust for though in the tune.
John I have always wondered about where the cars are tuned compaired to where you race. Mine was tuned about 10 miles from IRWINDALE DRAG STRIP and would like JOEL and JOHAN to please comet on this subject. Now where i live i am at 653 ft and thats pertty close to IRWINDALE at 380 FT. So should you tune FOR where you race or live or does it matter lol.
 

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Well, the dcx platform does make adjustments for altitude changes to some extent.
The duramax(i tune those also) has different tables used for elevation changes (so in your case those tables where probably not used where you where tuned due to the elevation difference), where as the dcx does not, dcx uses one axis for the major tables used in the calibration called p-ratio, which is your map/baro, so it will always take elevation into account based on your baro read.
I personally also make the tunes a little different if you are at higher elevation.
Hope that helps.
 
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Johan is correct. The Chrysler ecu does take into account all atmospheric conditions (altitude, temp, etc). Its not completely necessary to have the vehicle in our possession to tune it. We can get a truck just as dialed In via email if we have good data logs from the customer. Just remember that u lose about 3% of your power for every 1000ft you are above sea level when you are NA.

J
 

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johan is correct. The chrysler ecu does take into account all atmospheric conditions (altitude, temp, etc). Its not completely necessary to have the vehicle in our possession to tune it. We can get a truck just as dialed in via email if we have good data logs from the customer. Just remember that u lose about 3% of your power for every 1000ft you are above sea level when you are na.

J


Thank you Joel for your reply.
 

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my jeep has a cai, i plan on adding a borla s in the near future. with what i am reading about the loss in power with the exhaust i may add a tune as well. is an air fuel gauge/180 t stat absolutely necessary with the tune?
The Tstat not so much but the AFR gauge is crucial!! That should be one of the first mods to get along with a cmr tune. If you have a Trinity with the AFR gauge tied into it, any tuner can nail a tune much easier. If you don't have a wideband, most tuners will leave the tune pretty rich to be very safe. If they know what's going on, then they can lean it out to where it should be.
 

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Jerseyboy nailed my original tune via email....Lots of logs and revisions but got it perfect.

This was for a stroker and a supercharger application!
 
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