Diablosport Forums

Hi,

New user here. I just installed the MPG Booster Tune to my '08 Charger R/T (5.7) and have a few questions. I have 9r29 installed on my Predator and the only mod I'm running is a K&N drop-in filter.

• - What specific parameters are adjusted in this tune?
  - Can I use 87 octane safely without the risk of ping or knocking?
  - How does this effect long-term engine durability?

I guess I'm asking for specifics since I already know about the statement regarding the tune (1-2 MPG, MDS optimization, etc). Can anybody provide some insight?

Thanks, and great product. I'm looking forward to trying a few tunes over the summer at the track and on the dyno eventually.

-too many paramaters to list them specifically...
-If it is a 5.7, yes, if SRT8, 91 min.
-It will not...

Thanks for the info. I'll run my next tank on 87, set the cruise at about 70-75 on the way to work daily, and see how it does.

I'll post back with my results.

I'm running the MPG Booster tune on my '09 Hemi Ram. Is it supposed to make MDS (Fuel Saver) come on more often? I've been running the tune for a couple days, and it actually seems to be in Fuel Saver mode less often than with the stock tune. I haven't noticed an appreciable difference in mileage yet, but I haven't been on the freeway a lot.

I am curious what the basic changes are for this tune. Quicker upshifts? Quicker TC lockup? More MDS? Advanced timing?

Dave

I have noticed the shift points are much higher when you get on it, and my last tank (I installed the tune halfway through a tank of 89) actually showed reduced mileage from the previous tank (20.8 down to 18.3).

I have looked all over the internet and I can't find any true details on the tune. The above reply from Mike was pretty vague, unfortunately. I did datalog yesterday for about 8 minutes and only saw 1 degree of pulled timing briefly at 5750 or so RPM with the tune at WOT, so it's not hurting anything at least. I think I'll let it burn through this new tank of 87 and see what numbers I get. I've been keeping out of it and cruising at about 70-75 on the highway part of my commute to get an accurate number that will hopefully differ from stock.

I would expect that 87 octane would reduce the mpg, regardless of the tune in the '09+ hemis, because of the compression ratio. The 345hp hemis (which is what yours should have) should be able to run it, though. Please report back and let us know some longer term findings. I'm very interested.

Well, in my experience, the MPG booster tune failed miserably. The June 14 tank was all 87 Octane and the June 8 tank was 89 Octane.



And here are the stats since I drove off the lot with the car back in March.



So this tune just didn't work for me over the stock tune. Before we start talking about gas quality and all that, I think I should have seen some sort of increase instead of a decrease. The car shifted better and there was no ST or LT knock in the logs, but there was definitely nothing to gain from this tune economically (and with less power from the 87 as expected).

Over 400 views, so I'll just update this by saying I'm not trying to bash Diablo, the MPG tune just flat out didn't work for me. YMMV. On another note, the 91 tune is great. I filled up with a tank of 93, tried the 93 tune, got too much knock and then fell back to the 91 tune. Pretty sweet engine response and shifting out of this one.

I was thinking that the 87 tune was meant to save by allowing you to run cheaper gas safely without knock.

You mean the per cal 91oct, or perf 91 Oct

Dwifter wrote: Sat Jun 27, 2026 8:51 am You mean the per cal 91oct, or perf 91 Oct

this thread is from 2011