Noob custom tune question (06 SCREW 5.4)

Grabber523 · #1 Thu, February 5th, 2009, 03:59 PM

I have a custom DIDO with an X-pipe feeding 2 Magnaflow body mufflers. Stock manifolds and Cats and a K&N drop in filter. People rave about the custom tunes over the canned ones so I'm trying to decide what combination of octane, performance and tow to go with. I want to do an 89 tune for sure, but not sure whether to get tow or performance.

So I wonder:

Which would be a better all-around daily driver tune for best economy, the tow or performance? Either way I want to continue to run 89 octane. I'm also tossing around doing an 89 tow, 89 performance, then another performance or tow, either 91 or E85.

Which brings up another question:

E85 or 91? I know ultimately I should probably go with 91 and switch back to stock to run E85 since I want to feel the powaaaah! Any thoughts?

So to recap what I'm trying to decide:

1. 89 tow/performance
2. 89 performance/tow
3. 91/E85 performance/tow

What's everybody else usually run for DD?

Sorry I know this question is asked more than any other on this site, but I haven't really been able to find info specific to my possible tune choices.

Thanks a lot for your input!

Chris74 · #2 Fri, February 6th, 2009, 11:07 AM

I run 87 performance as my DD. Now I have been told that our gas up here in Canada performs very well......probably very similar to 89 in the U.S.

Anyway, it's an excellent "happy medium" of performance and economy for DD'ing!

Do not be scared of the 87 octane.........many good tuners will tell you that our 5.4's actually like the cheap gas pretty well and obviously can save you some cabbage!

Grabber523 · #3 Fri, February 6th, 2009, 11:13 AM

Cool, thanks man. Here in the "Corn Belt" our 89 is cheaper than 87 because of all the E10...even our "premium" (91) is an Ethanol blend. So Performance is the one to use DDing?

Chris74 · #4 Fri, February 6th, 2009, 11:21 AM

Yes......I recommend the performance tune as your DD'er!
Some guys like an economy tune though.

Grabber523 · #5 Fri, February 6th, 2009, 11:23 AM

Word! Thanks of the replies!

***Jackpine*** · #6 Fri, February 6th, 2009, 11:51 AM

Grabber, if you can stand it (I put a reply to this question in your "Hello" thread), I'm going to add to it here.

E85 has a high octane rating, but its available energy is lower than "real" gasoline. I don't know that you're going to feel "power" using it. (If I'm wrong here, everyone will be happy to tell me). :o And, E85 will give you much poorer gas mileage. If you find that it's cheaper though, things might balance out.

E10 has pretty much become the "standard". I imagine it might be difficult to find gas that doesn't have SOME ethanol in it through most of the country.

As I said in my other post, call Bill and discuss what you want with him. Ultimately, there will be some compromise. Find one you can live with.

- Jack