Board index (Legacy) Predator Technical Discussion Predator Dodge Gas 91 tune vs 93 tune

91 tune vs 93 tune

Predator support for Dodge gas vehicles

Moderator: mikel

Post Wed Apr 29, 2009 11:11 am

Posts: 53
Try Sinclair... I know there were a bunch in Oklahoma City when I was stationed there and their 93 octane allowed me to advance timing 5-6 degrees over other 93 octanes... This was in my 1.8t Audi of course though...

Post Tue Jul 28, 2009 7:32 pm

Posts: 124
I am seeing a lot of people complaining about getting kr with both 91 and 93 tunes with all brands of 93 octane fuel. Mutiple people on mutiple forums with either the 5.7L or 6.1 (primarally the 5.7L) Many say use 93 octane fuel with the 91 octane tune. Various people have done datalogging for kr, and find kr with either tune and 93 octane fuel in the tank.
Typically I would agree it is bad gas, but I have seen a lot of different people experiancing the same problem, and most just use the 91 tune to reduce the kr. I am wondering if someone at DiabloSport can look into this the next time they get their hands on an LX.

Post Tue Jul 28, 2009 8:35 pm

Posts: 1283
Got any logs or anything? Did these lot of different people log their stock tune first to compare? Do you think it effected their performance? or do you think it's going to do any damage or shorten their engine life?

Did you have this problem?

(my apologies. I just paid my back taxes with penalties. I'm not in a good mood)
2006 Magnum SRT8
AFE Stage II
Mopar Cat Back
185* T-stat
RDP tune by Steve

Post Sat Aug 01, 2009 10:18 pm

Posts: 136
I use Texaco 93 octane in my 08 Hemi Ram and it runs best on the 93 octane tune. It's ok on 91, but seems to pulsate some under hard acceleration like the torque management is playing with the throttle. Not so on 93 tune. I'm quite happy with the results.
I have added a Airaid MIT pipe with a K&N drop-in filter and a Magnaflow #16700 cat back system. I wonder if I should add a little fuel to compensate for the extra airflow?
2008 Hemi powered QC RAM

Post Wed Aug 05, 2009 3:45 pm

Posts: 6
I have made some initial logs on an 09 SRT Challenger and an 09 SRT Charger and with 93 octane in the tanks, they are getting knock on both the 91 and 93 tunes. On the 93 tune I am seeing anywhere from 3-6 degrees of ST Knock and on the 91 tune I am seeing anywhere from .5-3 degress of ST Knock. On the 93 tune both cars are running timing advance of only 14.5-18 degrees which seems really low to me. On the 91 tune, the cars are getting up to 20.5 degrees of timing advance. I am going to log the stock tune on the Challenger next for comparison, but so far the timing seems low to me and the cars don't feel any faster than stock. Next week I am planning on taking at least the Challenger to the dyno to do some fuel tuning.

Post Thu Aug 13, 2009 6:23 pm

Posts: 13
jara97 wrote:
Good question as I am wondering the same thing. I was using the 91 Octane tune but since I can only get 93 Octane I switched and I think the 93 runs better. I hope this can be cleared up as it is a confusing.


I ran the 91 cai tune with 93 octane gas for 3 tank fulls to see, by the way I have a 5.7 R/T '08 charger, and it felt ok, then I took it to the track and my best time was a 14.24 @99mph, I then, a tank later I put in 93 cai tune on the same 93 octane gas and holy friggin crap it felt way better, waiting to take it back to the track, mind you the low 14 sec run was in the south Florida heat, I thought I'd squeeze in a 14.0? with the 93cai tune or quicker, I also removed my Mopar cai and re-installed my SRT tube and box/ K&N drop in as well. to keep the engine heat out of the intake.

Post Sun Apr 21, 2019 7:18 am

Posts: 7
Well I am glad I came here. I've owned two Camaros and a Corvette .. all modded and always knocked on shell and Chevron. Right now I have a 6.1 hemi and she knocks on shell and Chevron a lot but when I put racetrack or quick trip it severely drops. I am going to switch to the 91 octane and keep using racetrack and quick trip.

Very useful thread!!


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