Octane rating

[Duck Vader]

A question for you about the tunes. Getting a custom tune done here shortly.

Any noticeable benefits to using a higher octane/performance tune on my 5.3?

Currently running 87 on the stock motor.

I have 92 here in Oregon and it's about $5-$10 more a tank than 87 and I use a tank a week. Still getting the rear end, transfer case, and transmission rebuilt but was curious for when I actually get a chance to run the tune along with the cai I picked up.

[DCIV]

Look into Torco, raises full points not decimals. I got two for my car based on my neighbor who has a 700+ hp mustang.


Coop

[Duck Vader]

That's just an octane booster. That's not what I'm talking about. I'm asking if worth running a tune designed for higher octane and thus using higher octane has any real benefits over a tune designed for 87 octane when it costs about $500 a year more in fuel.

[ChargerX3]

Yes octane is important. Especially on higher compression motors. I don’t know what yours is but build your tune to the fuel you have access to and will be using most often. Your gains will be minimal if you are looking to run on 87 though at sea level.

[Duck Vader]

My 5.3 was built to run on 87, but I have access to 92 and a custom tune based off running 91/93 and I'm at a couple hundred feet above sea level. Just wasn't sure how much better these engines perform on the higher octane and if worth the extra 500 a year.

[Chris GTO TT]

It basically just allows them to run more aggressive timing. I pretty much only run ACN catpiss 91 in my F150, but its factory tune is supposed to take advantage of the high octane.

Only way to really tell if it's worth it is to load the 92 tune and then the 87 tune and test them side by side.

[vr4]

TBH you probably won't notice a difference until you go cam/headers.

[Duck Vader]

More than likely I'll end up getting headers but doubt I'll get a cam for it.

Mechanic is going to open up everything Monday and let me know total damage. By the way it felt he is guessing transfer case is also going to need work. Depending on the transmission will determine what I decide to do. If I want to have him swap in a 4l80e, which requires a decent amount of work, or what. I'm kind of nervous. Lol.

[DCIV]

Have you kept up with how much you spent on the vehicle and all the repairs? Just curious if you could have gotten a low mileage one and had less issues?



Coop

[Duck Vader]

About $7500 total in between what I paid and needed repairs. Rest was stuff I wanted to do.

The g80 is just a matter of time no matter what you do.

Transmission hopefully is fine. But I'm having them rebuild parts of it anyway to extend the life. Transfer case is what I'm most worried about. When he was loading onto the trailer he said he thinks it might be messed up too.

[Duck Vader]

So will be starting to tune this hopefully next week. Has about a half tank left of 87. Still going back and forth between tuning for 87 or tuning for 92. From research I've seen I might get about 10 more crank hp out of the 92. Not sure if that is worth the extra 20-30 cents a gallon. That would be like I said, $40 more a month for maybe 5-8 rwhp and maybe one more mpg.

Don't really think it's worth it.

[ChargerX3]

How much is the tune? How much MPG will you improve? Your tune might not even be worth the cost in the long run.

[Duck Vader]

$175 custom tune. Found an unmarried diablo i3 on fb for $200, so $375 total and comes with free retunes for 1 yr and reduced rate tunes for lifetime Reviews say about 2-3 mpg gain and 15-40 hp depending on supporting mods.

[Duck Vader]

It's more about the transmission side. Tune will also help with that.

[ChargerX3]

Why do i get the feeling the tune is going to increase fuel consumption.

eelout: