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All problems are fixed for now BUT my 09 Challenger RT is getting terrible gas milage. Example: before the 93 CAI tune 20 mpg in town NOW with the 93CAI tune 14.1mpg. I have a catch can, resinator delete with deltaflow Flowmasters, and of cource a CAI. Can I tune anything up or down to try to help. PS this is actual gas milage and not the computer. Kev

Drive it exactly the same way. I found when driving it exactly the same way I get an increase in mpg with the 93 tune. Many enjoy the newly found power and use it, so then by getting on the throttle harder the mpg goes down, not because of the DS tunes.

kev2.5 wrote:All problems are fixed for now BUT my 09 Challenger RT is getting terrible gas milage. Example: before the 93 CAI tune 20 mpg in town NOW with the 93CAI tune 14.1mpg. I have a catch can, resinator delete with deltaflow Flowmasters, and of cource a CAI. Can I tune anything up or down to try to help. PS this is actual gas milage and not the computer. Kev

I got the same thing with my Charger RT running 93 CAI tune. That was even with the MDS on. Switched to the 91 CAI tune and turned off MDS and getting better mileage.

cheesewizard wrote:

kev2.5 wrote:All problems are fixed for now BUT my 09 Challenger RT is getting terrible gas milage. Example: before the 93 CAI tune 20 mpg in town NOW with the 93CAI tune 14.1mpg. I have a catch can, resinator delete with deltaflow Flowmasters, and of cource a CAI. Can I tune anything up or down to try to help. PS this is actual gas milage and not the computer. Kev

I got the same thing with my Charger RT running 93 CAI tune. That was even with the MDS on. Switched to the 91 CAI tune and turned off MDS and getting better mileage.

This ^ I've constantly heard bad things about the 93 octane tunes on the predator, the 91s are the best.

Well, I will try the 91 tune. It seems funny that none of the Diablo guys will respond to this post. If there's no fix just tell me and I will tune a different way. Thanks Again.

We dont touch anything in the part throttle/cruise area of the tune that would affect mileage negatively.

I fail to see where the 91 vs. 93 octane tune thing fits in here at all either?

This whole 91 tune is better is just plain silly. If you feel the 91 tune is better, it means the 93 tune does not like your 93 octane fuel. Period.

There is no vehicle on the planet that will make better power with the 91 tune than the 93 tune if there is no KR and good fuel in the tank. I mean, do you guys think we just make this stuff up?
If the 91 tune was so much better, why would we continue to swear to you guys that the ONLY difference between the 2 tunes is how much timing is commanded at WOT?

Seems most 93 these days is inferior crap. Its the damn Ethanol. The Hemi doesn't like it. Its supposed to have a higher octane then gas, so are they using it as a booster? That could be the problem. If they were adding it to real 93 octane I think it would work better.

I've been talking to some people about the Fitch Fuel catalysts. I think I may give it a shot. Supposedly it adds 1-2 octane points and can improve mileage. My gut said Bullshit, but after reading some articles and talking to the VP of the company, it seems like it may actually work.

Just B.S It dose not work waste of money

Mike_Levy wrote:Seems most 93 these days is inferior crap. Its the damn Ethanol. The Hemi doesn't like it. Its supposed to have a higher octane then gas, so are they using it as a booster? That could be the problem. If they were adding it to real 93 octane I think it would work better.

I've been talking to some people about the Fitch Fuel catalysts. I think I may give it a shot. Supposedly it adds 1-2 octane points and can improve mileage. My gut said Bullshit, but after reading some articles and talking to the VP of the company, it seems like it may actually work.

FWIW, the VPs of some of the HHO conversion companies would likely make you believe that works too....but I can tell you that unless you are running a carb'd vehicle (and even then...), theres no chance in hell.

mikel wrote:We dont touch anything in the part throttle/cruise area of the tune that would affect mileage negatively.

I fail to see where the 91 vs. 93 octane tune thing fits in here at all either?

This whole 91 tune is better is just plain silly. If you feel the 91 tune is better, it means the 93 tune does not like your 93 octane fuel. Period.

There is no vehicle on the planet that will make better power with the 91 tune than the 93 tune if there is no KR and good fuel in the tank. I mean, do you guys think we just make this stuff up?
If the 91 tune was so much better, why would we continue to swear to you guys that the ONLY difference between the 2 tunes is how much timing is commanded at WOT?

As a consumer of the product YOU support I would think people should be able to come to this site and voice their experiences without getting major attitude from you. Do you honestly think people have made this stuff up about their cars running better on 91 than 93? Could there be that many stations with bad 93 gas from all areas of the country? Judging by how aggrevated you are by this there should be plenty of people having this problem. With my car on 93 I can barely get 16mpg with a mix of city/hwy. On the 91 tune I can get 18mpg in city only driving. Same driving style.

Not only does the mileage suffer in the 93 tune but also the erratic behavior of the transmission. It shudders like mad on decel and generally shifts inconsistantly. Especially downshifting to 2nd and 1st gear. Can you explain that? I put in the 91 tune and no more issues with trans shudder or shifting. Overall the car doesn't like the 93 CAI tune. Believe me or not. I drive this car every single day so I have first hand experience with how my car is acting and it's aggrevating that I can't use the 93 CAI tune. This car doesn't like it, PERIOD.

You need to keep in mind that some of us consumers don't have the expertise and knowledge that DiabloSport representatives have and we are going on real world experiences of how this product is interfacing with our vehicles.

There is another issue.
It is not the tunes.
I will be glad to show anyone who wants to see every table modified in the 91 and 93 tunes, and aside from how much timing is commanded at WOT, they are exactly the same.

cheesewizard wrote:

mikel wrote:We dont touch anything in the part throttle/cruise area of the tune that would affect mileage negatively.

I fail to see where the 91 vs. 93 octane tune thing fits in here at all either?

This whole 91 tune is better is just plain silly. If you feel the 91 tune is better, it means the 93 tune does not like your 93 octane fuel. Period.

There is no vehicle on the planet that will make better power with the 91 tune than the 93 tune if there is no KR and good fuel in the tank. I mean, do you guys think we just make this stuff up?
If the 91 tune was so much better, why would we continue to swear to you guys that the ONLY difference between the 2 tunes is how much timing is commanded at WOT?

As a consumer of the product YOU support I would think people should be able to come to this site and voice their experiences without getting major attitude from you. Do you honestly think people have made this stuff up about their cars running better on 91 than 93? Could there be that many stations with bad 93 gas from all areas of the country? Judging by how aggrevated you are by this there should be plenty of people having this problem. With my car on 93 I can barely get 16mpg with a mix of city/hwy. On the 91 tune I can get 18mpg in city only driving. Same driving style.

Not only does the mileage suffer in the 93 tune but also the erratic behavior of the transmission. It shudders like mad on decel and generally shifts inconsistantly. Especially downshifting to 2nd and 1st gear. Can you explain that? I put in the 91 tune and no more issues with trans shudder or shifting. Overall the car doesn't like the 93 CAI tune. Believe me or not. I drive this car every single day so I have first hand experience with how my car is acting and it's aggrevating that I can't use the 93 CAI tune. This car doesn't like it, PERIOD.

You need to keep in mind that some of us consumers don't have the expertise and knowledge that DiabloSport representatives have and we are going on real world experiences of how this product is interfacing with our vehicles.

I have a question for you. Do you really believe that all of us would tell you that the 93 tune dose not work well with most of the 93 oct gas that you can get. One reason for the fuel mileage to go down with bad gas is the pcm is pulling timing. Mikel dose not have a bad attitude he giving you the facts but you refuse to listen. No one can help some one who will not listen.

Well put Brandy.....If you already made up your mind as to the answer, why ask the question?

I hate that this turned into a bad situation. Don't get me wrong, we are a Diablo family with Fords and Dodges. The Fords have responded great especially the Ford SuperDuty with tons of power and better fuel mileage. That is why I asked the question about the 09 Challenger RT: throttle seems slugish and honestly the MPG on the 93 CAI went to crap. I do believe you about the program being the same except for WOT timming and that IS my point and I wanted you (Diablo guys) to know about the bad MPG on the Challenger RT. Is it only the Challenger or has there been other vehicles with a huge change in MPG for the bad? I just want to try to figure this out. I am a gear head and love this stuff BUT i also know that I am not driving a 1000hp street ride BUT sure seems like I am feeding one at the pump.Thanks Again

Please try the 91 tune and see what happens. The only reason for the 93 tune to use more gas would be a lead foot and crapy 93 oct. There is one more thing you can do to figure this out. Do a data log to see how much long term and short term knock you are getting with the 93 tune and then log the 91 tune. Post your logs here and some one will help you.