Running Octane Higher than Tune Rating

[laterider]

I simply could not remember last time I filled up, was it 89 or 93 I put in there? I really think 93, but I sometime can't remember if I shut the garage door - so this morning when I loaded a Tune from the Brenspeed tuner I got yesterday, I selected the 89 Tune because I didn't want to have detonation, knock, etc. But, since this is a custom tune, is doing this a mistake? I've got half a tank to go, then I'll fill with 93 and load the 93 tune, but am I asking for trouble, should I go back to stock until I fill up? I really wouldn't think there would be an issue, but I am a newb at this... Too much traffic on the way to work this morning, but I did notice: 1) Didn't have the throttle lag I remember. 2) shifts seem different - more crisp. 3) the same car, with subtle differences. 4) Did I remember to shut the garage door?... Waiting to fill with 93 so I can check out that tune for sure!!!

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[Sancho805]

well from what you said, you either have 89 or 93 in your half-full tank. just run your 89 brenspeed tune until ur on empty then fill up with 93 and load the 93 tune. no need to go back to stock.

so you only feel a subtle difference? are you running with an oversized CAI or factory air box? can't remember.

[laterider]

Originally Posted by Sancho805

so you only feel a subtle difference? are you running with an oversized CAI or factory air box? can't remember.

LOL... No I have the factory air box. The tuner was part of my plan as I begin mods, next on the list is gears (or takeoff 8.8, I'll post the reason why after I take some pics). For some reason I just didn't find a CAI I was happy with the looks of and decided against it for now. Actually I think the FRP one looks the best (like it came with the car), but that comes with the FRP tuner box, so If I can ever find one on ebay and get Doug to do a tune for it.. well I will have spend more money than a combo...

I was in bumper to bumper traffic this morning and really didn't have a chance to get on it, then I was on the base. Tonite I plan to further investigate.

How many of U carry your Tuner in the trunk in case you are close to empty and can't get 93???

[Nuke]

You can run a higher octane than the tune calls for with no problem other than wasting a few bucks. Most of the difference between stock a nd a custom tune can be felt when going WOT from either a dig or a roll in addition to the driveability improvements you've mentioned.

I carry my tuner in the car since I run an 89 tune 99% of the time and I've had 2 occassions where I could only get 87 octane while on a road trip.

[laterider]

Ok, got to drive some more, more time to check it out than the traffic jam to work this morning. In addition to what I mentioned, on the bottom end it seems like there is more to be had, and when getting on it as the engine was reving up, like it had more coming on.
I do like:
1) The missing throttle lag
2) The shifts - see more below
3) The extra I think I feel

Ha, the pic is in no way a cool burn out, but at work after backing out of the space I stomped it and both wheels immediately started spinning. I let off right away, I need these tires for a while. Hmm, its not posi, but we know this can happen in some situations..



All of the shifts seem more firm, crisp, I guess this feel comes from changing the RPM of the shift. They just feel better, like the points let the engine come up a little better. What I did notice is that although it feels better on all shifts, that upshift to overdrive can still have that less than good feeling if your foot is not in it. I want to continue to check that shift out and want to feel it with the 93 tune. All in all this is fun way to spend just under $400. lol. Hoping the gear swap will keep me smiling too. :-) If it seems I don't know what I'm talking about concerning shift points, consider me a newb idiot and carry on!!!

[Sancho805]

a more noticeable difference can be felt with a oversized CAI. that factory airbox is VERY restrictive. the tune is still being held back. i think the best bang for buck on a "full" CAI is the JLT and DeMolet. i almost pulled the trigger on a DeMolet until i found a used C&L for sale which is what i'm running right now. i think they also offer color choice on the intake tube.

i have personal experience with different CAI setups running the same tune. you still have more noticeable performance to gain with the proper setup. basically, upgrade your setup before you judge your tune.

[157db]

3 words


waste of money

[laterider]

Originally Posted by Sancho805

i have personal experience with different CAI setups running the same tune. you still have more noticeable performance to gain with the proper setup. basically, upgrade your setup before you judge your tune.

Thanks Sancho, the more I drive it the more my opinion actually goes up for becoming a Brenspeed Fan and may never make it too needing a different tune from elsewhere (I think you made that comment in another post). It continues to make me smile as there is a definite improvement in 'a dig' and shifts, and more. I am itching to get the last of the gas out of the tank and try the 93 tune, but I could be happy with running the 89 tune if gas goes up more.
I gotta cut it out, but parked in the same spot today at work, then I did more than just stomp and release when leaving today. LOL - put another set of marks down almost directly on top of the pair from yesterday, this time with the right side being very heavy. Too much fun, but I'm gonna break somethin or get a ticket soon.

I also notice now I seem to get up to 80 around town when I was getting up to 60 before. Again I gotta take it easy!!! Look out with the 93T!!!

[laterider]

Originally Posted by 157db

3 words


waste of money

LOL!!! 157 you are always able to give a no bs answer to one's question!!!