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Hi everyone, I have just installed my diablo two days ago after updating it through diablosports.com and my current version is v.8r20 and so far everything was fine, till I decided to play around with the parameters :dead1:

First I've chosen the Diablo Performance Tune with CAI (I have Volant CAI) and modified its parameters, raised the rev. limiter in neutral to 5000rpm and disabled the auto shift and installed the Tune... then I drove the car, with the manual shift on 1st I hit it and when the rpm reached around 6000rpm the computer shut down and the check engine icon start flashing!!! I had to stop on the side of the road and had to re-start the car and everything was fine except the check engine icon ...

So I cleared the error and reset the parameters but the car did the same thing again, so I manually changed the parameters to where they were (stock auto shift and 4000rpm on neutral) but I started to hear a loud noise from my exhaust! my brother said it might be because of the extra power I have which my stock exhaust can't handle ...

To find out the source of the problem I restored the original backup and the car is back to stock, and the loud noise is no longer there !!! so is't true ? my exhaust can't handle the extra power ???

I need your help with these issues guys ... I'm getting a MagnaFlow pretty soon and I'm planning to disable the MDS but not sure what are the implications of disabling the MDS! any idea?

And what should be the safe rpm rev limit while driving the car? 5500rpm !!
 

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Hi everyone, I have just installed my diablo two days ago after updating it through diablosports.com and my current version is v.8r20 and so far everything was fine, till I decided to play around with the parameters :dead1:

First I've chosen the Diablo Performance Tune with CAI (I have Volant CAI) and modified its parameters, raised the rev. limiter in neutral to 5000rpm and disabled the auto shift and installed the Tune... then I drove the car, with the manual shift on 1st I hit it and when the rpm reached around 6000rpm the computer shut down and the check engine icon start flashing!!! I had to stop on the side of the road and had to re-start the car and everything was fine except the check engine icon ...

So I cleared the error and reset the parameters but the car did the same thing again, so I manually changed the parameters to where they were (stock auto shift and 4000rpm on neutral) but I started to hear a loud noise from my exhaust! my brother said it might be because of the extra power I have which my stock exhaust can't handle ...

To find out the source of the problem I restored the original backup and the car is back to stock, and the loud noise is no longer there !!! so is't true ? my exhaust can't handle the extra power ???

I need your help with these issues guys ... I'm getting a MagnaFlow pretty soon and I'm planning to disable the MDS but not sure what are the implications of disabling the MDS! any idea?

And what should be the safe rpm rev limit while driving the car? 5500rpm !!
I haven't run the newest revision however from the information that you've posted the new tune may not be the culprit. The rev limit in drive needs to be raised along with the auto shift disable to shift manually above the stock limit. Try raising the rev limit to 7000 rpm in drive and see what happens. Your exhaust is not the problem. having a stock exhaust may rob you of a little horsepower(5-10) but it will not cause the PCM to go into limp mode. Bumping off the rev limit will always induce limp mode and a key cycle is the cure. MDS is not the problem either, disabling it will help drone but affect little else except good gas mileage.
 

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Discussion Starter #3
Midnightsun, that really makes sense especially that the car PCM goes into limp mode when I go over the 5500rpm :thinking: But is there any risk raising the rpm to 7000 ?

Am also curious about the noise I hear when when I applied the CAI performance Tune ... the only performance mod I currently have is the CAI so do you suggest using the 93Octone Performance Tune or should I use the CAI Tune ?

Regarding the MDS I think am going to get the Corsa (I just got a good deal) so that shouldn't be an issue anymore :biggrin:
 

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Midnightsun, that really makes sense especially that the car PCM goes into limp mode when I go over the 5500rpm :thinking: But is there any risk raising the rpm to 7000 ?

Am also curious about the noise I hear when when I applied the CAI performance Tune ... the only performance mod I currently have is the CAI so do you suggest using the 93Octone Performance Tune or should I use the CAI Tune ?

Regarding the MDS I think am going to get the Corsa (I just got a good deal) so that shouldn't be an issue anymore :biggrin:
KR is the key to a safe tune. There may be a false KN on our engines, especially with a "tall" cam, but regardless if you monitor and stay below the KN threshold you should be safe. As a general rule, the worst knock will happen at peak torque, which is down in the 4-5K rpm range so higher rpms will generally not be a knock sensitive area. I am thankful to your query to the to 7k, which is not a suggestion to where you should manually shift but a suggestion to raise the limp mode enable threshold beyond where you would be shifting. Prudence should dictate that a stock 5.7 should not venture far beyond the 6.2K limit. A balanced rotating assembly or upgraded harmonic balancer will raise that limit.

The intent of my suggestion is to alert you to the fact that it takes two adjustments in the Predator to actuate the higher shift points above stock...the raised shift rev limit in drive and the disabling of the auto shift feature.

In regards to the "noise", you have a finely tuned ear if you can hear knock in our engines as it is a deceptive sound that most cannot hear. If you can in fact hear detonation you are of a select group and should consider an appropriate profession in music or acoustics! That is nothing more than a sincere a compliment!

If you have a CAI then use the appropriate CAI tune correspondent to your octane rated gas. If you are using 91 octane gas use the 91 octane CAI tune.

In regards to the Corsa, I think that they have applied the requisite science to their R&D and consequently have produced a product that gives what is advertised. I think that you will be very happy with your choice if the elimination of drone and quited idle is your goal.

IMHO the Predator is an amazing product and a quantum leap forward for our DCX platform engines. It gives us the power, but it is up to us to use it wisely.
 

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Discussion Starter #5
Thanks for compliment :dance:

Anyway I will take your advice on the relation of the autoshift and the higher rev. limit ... I will test it and post back the results - although I don't want to harm the engine :dead1:
 

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I run my 5.7 to 6700 rpm and installed it last december,no problems with my motor,it will be fine
 

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I run my 5.7 to 6700 rpm and installed it last december,no problems with my motor,it will be fine
A couple quick questions:
Is the 6700 attainable with autoshift or just manual?
How often have you reached 6,700 rpm?

The reason for my question is that the only way I can reach those rpms is with the auto shift disabled with my AWD. Also, the stock harmonic balancer and crank of the 5.7 is not rated above 6200 rpm. It may perform well above that rpm limit a few times but it may not last long if you persist. When I had my crank balanced (6.1 replacement) there was a fair amount of drilling and weighting even with it, and it is rated to 6,600! Maybe more a word of caution than a question.
 

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I am running 93 cai tune,the 6700 rpm shifts in auto and manual,I reach 6700 rpm quite a lot especially in 2nd gear,it gets to 80 in 2nd then bang into 3rd and just keeps pulling.I dont get much chance to pull 6700 in 3rd as I tend to run out of road cos I'm already doing 80 in 2nd.Obviously if I dont want to pull 6700 rpms I shut off and let the tranny do its thing.
I'm running v18,I tried v20,it was crap,so I went back to v18,so you may have different speeds with v20 as I had tranny issues with v20
 

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KR is the key to a safe tune. There may be a false KN on our engines, especially with a "tall" cam, but regardless if you monitor and stay below the KN threshold you should be safe. As a general rule, the worst knock will happen at peak torque, which is down in the 4-5K rpm range so higher rpms will generally not be a knock sensitive area. I am thankful to your query to the to 7k, which is not a suggestion to where you should manually shift but a suggestion to raise the limp mode enable threshold beyond where you would be shifting. Prudence should dictate that a stock 5.7 should not venture far beyond the 6.2K limit. A balanced rotating assembly or upgraded harmonic balancer will raise that limit.

The intent of my suggestion is to alert you to the fact that it takes two adjustments in the Predator to actuate the higher shift points above stock...the raised shift rev limit in drive and the disabling of the auto shift feature.

In regards to the "noise", you have a finely tuned ear if you can hear knock in our engines as it is a deceptive sound that most cannot hear. If you can in fact hear detonation you are of a select group and should consider an appropriate profession in music or acoustics! That is nothing more than a sincere a compliment!

If you have a CAI then use the appropriate CAI tune correspondent to your octane rated gas. If you are using 91 octane gas use the 91 octane CAI tune.

In regards to the Corsa, I think that they have applied the requisite science to their R&D and consequently have produced a product that gives what is advertised. I think that you will be very happy with your choice if the elimination of drone and quited idle is your goal.

IMHO the Predator is an amazing product and a quantum leap forward for our DCX platform engines. It gives us the power, but it is up to us to use it wisely.
I have a question. Are you saying that raised shift points will not work unless you disable auto upshift? I thought that all you had to do was raise shift points and raise the rev limiter in drive to get the raised shift points to work. I hope I just learned something here. The car will have raised shift points in D also or just in autostick? Thanks
 

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I am running 93 cai tune,the 6700 rpm shifts in auto and manual,I reach 6700 rpm quite a lot especially in 2nd gear,it gets to 80 in 2nd then bang into 3rd and just keeps pulling.I dont get much chance to pull 6700 in 3rd as I tend to run out of road cos I'm already doing 80 in 2nd.Obviously if I dont want to pull 6700 rpms I shut off and let the tranny do its thing.
I'm running v18,I tried v20,it was crap,so I went back to v18,so you may have different speeds with v20 as I had tranny issues with v20
My experience has been that at WOT with the auto shift disabled, and rev limit raised to 7,000 rpm, that if the shift does not occur prior to 6,600 rpm the car will go into limp mode. When I am at partial throttle I can go up to 7000 rpm. If I have auto shift enabled the shift is at 6,200 rpm.

I wonder why our cars shift differently? It may be that it is because of mine being a AWD with different gearing (3.07) or maybe the overseas production has a different TCM?

I would again caution you that with the stock 5.7 crank and balancer you are tempting fate if you shift above 6,200 rpm. At the very least you should routinely check the dampener for signs of wear along with the belt.
 

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I have a question. Are you saying that raised shift points will not work unless you disable auto upshift? I thought that all you had to do was raise shift points and raise the rev limiter in drive to get the raised shift points to work. I hope I just learned something here. The car will have raised shift points in D also or just in autostick? Thanks
My experience is that raised shift points in auto will only get me to 6,200 rpm. To get higher than that I must shift manually.
 

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I'll tell you what I did n see if its what you did,here goes.Raised shift points to 6700 rpm,disabled auto upshift,shift firmness on,TCM off,basically everything to the MAX,left o2 sensors alone,left fuel and timing alone,fan settings around the 200 mark(cant remember the actual settings I set but the fans dont come on full time and the needle stays at mid point and no CEL's)speed limiter to 190 mph(never gonna get there in there in the UK but you never know but at least it sounds impressive.lol)did a data log and it showed a glimmer of KR at WOT(slow mo mode on pc,couldnt see it at normal speed on pc)been running this for last 4 months and no probs yet on v18 except for idle surge on coldish mornings for about 10 seconds.Bonus factor is that with normal driving mpg is up,only by 2-3 mpg but at least when I floor it at 30 mph it lights the rear tyres up.You pays your money,etc,etc.
 

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I'll tell you what I did n see if its what you did,here goes.Raised shift points to 6700 rpm,(mine @ 7000)disabled auto upshift,(yup)shift firmness on(yup),TCM off(not sure what this is),basically everything to the MAX,(yup)left o2 sensors alone,left fuel and timing alone(I played with my fuel and timing tables quite a bit but it never effected the shifting),fan settings around the 200 mark(cant remember the actual settings I set but the fans dont come on full time and the needle stays at mid point and no CEL's)speed limiter to 190 mph(yup)(never gonna get there in there in the UK but you never know but at least it sounds impressive.lol)(you never know until you try.:) )did a data log and it showed a glimmer of KR at WOT(slow mo mode on pc,couldnt see it at normal speed on pc)been running this for last 4 months and no probs yet on v18 except for idle surge on coldish mornings for about 10 seconds.Bonus factor is that with normal driving mpg is up,only by 2-3 mpg but at least when I floor it at 30 mph it lights the rear tyres up.You pays your money,etc,etc.
It sounds like life is good for you. I wish I could get my car to auto shift at 6700. It is a little nerve racking trying to shift 6600 manually in 1st gear when I have to hit shift at 5700 because of the lag. There is little room for error.
 

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I don't get a lot of this..! (duh) I'm thinking about getting the predator and a CAI but can't afford an exhaust upgrade yet. Question; am I waisting my time without doing the exhaust too?!
 

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uhhhh

:pat: A Couple questions about the diablo. They claim that I will get better mpg. How is it getting me better mpg? Also, what about using the diablo at higher altitudes? Im in SLC at 5000^ feet. I heard i should use the 91 octane (highest we have) and use the 93 tune because it burns differently at this altitude. !? !?
 

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It sounds like life is good for you. I wish I could get my car to auto shift at 6700. It is a little nerve racking trying to shift 6600 manually in 1st gear when I have to hit shift at 5700 because of the lag. There is little room for error.
manually???,I never use manual.I stick it in "D" and let the tranny do the dirty.The only time I use manual is if something behind me thats pushing me that I'm not sure of,then as long as your below 80mph shift it to 2nd gear then you're good to go(with predator installed otherwise its 65-70mph).If you have the pred installed and you're at 30 mph ish,shift to 1st but get get ready to shift to 2nd real soon,you will smoke just about anything that challenges you,"There goes the last contestant"
 

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:pat: A Couple questions about the diablo. They claim that I will get better mpg. How is it getting me better mpg? Also, what about using the diablo at higher altitudes? Im in SLC at 5000^ feet. I heard i should use the 91 octane (highest we have) and use the 93 tune because it burns differently at this altitude. !? !?
I havent a clue what my altitude is in the UK,tune your Pred and judge it by the seat of your pants.My motor is stock,I run 93 CAI tune(no cai,cos all it does is make your motor sound like its struggling for air)340 hp is enough for anyone,its how you utilise it that counts and that's what the diablo(italian for the"DEVIL")does with rpm limits and shift limits.All my ass knows is that when I go back to factory tune(warranty issues) the "C" is so much slower.Getting back to mileage,it stands to reason if you dont need so much pedal to sustain a constant speed,you aint using gas but who the [email protected] cares,if you got a hemi,run it.You didnt buy a hemi for mpg,you bought it for mph and hp,correct me if I'm wrong
 

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You should also join the Diablosport forum at DiabloSport :: Gas and Diesel Tuning Systems. There is a forum for the Predator Dodge Gas group that applies to us. You can get answers direct from the devils mouth as it were.

jimt
 

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A Couple questions about the diablo. They claim that I will get better mpg. How is it getting me better mpg? The canned Diablo tunes leans the A/F a little so the engine is burning the available gas more efficiently. Also, what about using the diablo at higher altitudes? Im in SLC at 5000^ feet. I would imagine that the PCM pulls fuel in response to the thinner air. I heard i should use the 91 octane (highest we have) and use the 93 tune because it burns differently at this altitude. !? !? Always match the octane rated tune for the same octane rated gas. If you run the 93 tune with 91 gas you will be asking for detonation. As a rule of thumb the higher octane gas allows the timing to be advanced, which creates more combustion pressure, which give you more power.
 
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