Anyone switched to 87 octane?

HEMIMANN

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So I wonder then, how "long term" are the "lt" tables. For those who are getting knock, it might be better then to pick an octane and run with it permanently, instead of switching back and forth with towing etc. If it takes longer than a tank for the LT table to update then the silly thing is permanetly confused as we mix and match octanes.

You guys are convincing me to go back to 89 full time.
Now tell me if 91 really benefits the Hemi compared to 89.

Did I mention how much I hate software? Gimmee back a screwdriver and actuator screw!
 

CheechDogg.0n37s

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You guys are convincing me to go back to 89 full time.
Now tell me if 91 really benefits the Hemi compared to 89.

Did I mention how much I hate software? Gimmee back a screwdriver and actuator screw!
Try 91 out , I am back to 91 full time after running 89 for a whole year like I have said in previous posts and my truck just feels strong, from shifting to acceleration, the difference is undeniable and very noticeable ...

Also my MPGs went up almost 2 mpg which I don't mind at all lol .... it's going to benefit the "HEMI" no doubt ....
 

HEMIMANN

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Try 91 out , I am back to 91 full time after running 89 for a whole year like I have said in previous posts and my truck just feels strong, from shifting to acceleration, the difference is undeniable and very noticeable ...

Also my MPGs went up almost 2 mpg which I don't mind at all lol .... it's going to benefit the "HEMI" no doubt ....

Does your 91 have ethanol blend? If so, how much?
 

HEMIMANN

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No ... 89 doesn't either ...

Both of ours has 10% ethanol mandated by state law, via agrigiant bribery .

There are nonoxy 91 pumps dedicated to small engines, but nobody enforces use compliance.
I'll try the 91/10 blend. We don't need to add supplemental alcohol in winter to prevent gas line moisture freeze up.
 

Hemi395

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You guys are convincing me to go back to 89 full time.
Now tell me if 91 really benefits the Hemi compared to 89.

Did I mention how much I hate software? Gimmee back a screwdriver and actuator screw!
Amen, I miss the days of adjusting a screw on a carb and tweeking the distributor a bit to tune your motor
 

kayjo

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at 2mpg difference, it offsets the price for me right now. I am going to give more octane a try. Ive been cheap because not having any problems with 87.
 

Hemi395

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So I wonder then, how "long term" are the "lt" tables. For those who are getting knock, it might be better then to pick an octane and run with it permanently, instead of switching back and forth with towing etc. If it takes longer than a tank for the LT table to update then the silly thing is permanetly confused as we mix and match octanes.
I agree, stick with one fuel. Unless they've updated the PCMs on newer trucks, the "learned" data from Knock is erased every time you the truck has a cold soak. When I ran 87 it would knock like crazy for a bit until LT started every time cold started. But mines a 2013 sp it's possible the newer trucks have a longer memory
 

CheechDogg.0n37s

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Ethanol free gas is a whole different thread lol
That is one of the reasons out here in California we get better mpg with 91 .... I do remember when working for Dish network and we went to the east coast and the 91 out there had ethanol and we were getting questioned about the amount of times we filled up the trucks and vans with gas lol all due to the ethanol blend ...
 
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