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Tuning on 90 octane

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404
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Location
Anchorage
#1
Hello everyone,
I'm brand-new to engine tuning, but would like to get more power out of my FiST. Unfortunately, I am stuck with crappy 90 octane gas here in Alaska, and would like to solicit input on the best way forward to make reasonable, mild gains. What would be the best path forward? I'd like to stay with the factory turbo, for now, and my autocross class (STH) doesn't allow intercoolers, any intake path mods past the turbo inlet, and requires a cat close to where the stock unit is. Any ideas?
 


Messages
119
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39
Location
Naples
#3
Does the Access port allow tuning to different octane fuel- 87, 89, 91, 93? I was thinking of getting one to tune it to E85 but read that these cars cannot run on E85. 93 octane is very expensive and can be hard to find sometimes- especially before and after a hurricane in my area. $500 is a lot to spend for the Ap on my commuter car but it would be nice to have more power in first and second gear.
 


Messages
155
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83
Location
Broward county Fl
#4
Yes it allows tuning in different octanes.
It comes with 3 stages of tunes and each stage has 87,90, and 93 octane tunes.
better yet get a canned tune from Stratified or Dizzy and enjoy buying new tires more often because you
will be smoking them in 1st,2nd and 3rd.
 


Messages
28
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5
Location
Anchorage
#6
Hello OP! I am another Alaskan here and most companies will adjust a tune for lower octane

Sent from my SM-G965U using Tapatalk
 


danbfree

3000 Post Club
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Tigard, Oregon, USA
#7
Does the Access port allow tuning to different octane fuel- 87, 89, 91, 93? I was thinking of getting one to tune it to E85 but read that these cars cannot run on E85. 93 octane is very expensive and can be hard to find sometimes- especially before and after a hurricane in my area. $500 is a lot to spend for the Ap on my commuter car but it would be nice to have more power in first and second gear.
91 tunes should work fine, the AP comes with basic conservative ones but you can get tunes from real tuners as well for $75 or less. Also AP's are sold used ALL the time for ~$350 used, they are allowed to uninstalled from a car and resold as many times as you want. BUT the REAL power comes from an e30 tune, you just add 3 gallons of e85 per full tank, literally just this tune alone will give you 50 fwhp / 80 fwtq with NO other mods!
 


Messages
10
Likes
7
Location
Fairbanks, AK
#8
I know I'm bringing this up a year later, but I'm also in Alaska and just got a FiST in August 2019 or so. I bought the Mountune FB3 package, and haven't put the intercooler on, and my RMM hasnt even shipped.
I ordered the package, and then it snowed. I want to utilize the 45 day free tuning but I can neither get traction in 3rd or 4th, nor do I have anywhere I can safely drive that fast now. Also, I'm stuck with 90 octane as the best I can get.
For kicks, i set up the gauges and have been watching the knock sensors and octane learn ratio, and it's all been fine on 90. OLR at -1.00. Occasional transitional knock...

I contacted Randy at Mountune about postponing the free tune session till next summer. I think it's going to cost me but I'm ok with that. My bad timing.
Also asked him about the 90, with often only 87 available. I also asked about the "Bad gas/panic mode." Here's his reply after I asked for clarification..

Bad fuel would mean the appropriate octane that is not good quality, as you will run into once in a while. This is not for octane levels that we do not support, as indicated on our site. It’s not for less than 91 octane. We don’t have official support for 90 octane.

You selected 91 octane on your order. You can try to use 90 octane, but I make no guarantees about the output. Just wanted to be clear about that.


His first reply:
I can usually offer a price break for repeat customers. Just talk to me first.

As for 90 or 87 octane, those are not supported officially. I'd use Stage 0 in those scenarios.


So, based on his reply I should used Cobb Stage 0, which I think is stock, but I don't know for sure. I've used higher settings and its drastically better, plus my observations show no learning for it to limit based on octane.

We'll see next summer I guess!


Btw, I plan to try autocrossing this car next year around AK, it should be a blast!
 


danbfree

3000 Post Club
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Tigard, Oregon, USA
#9
I know I'm bringing this up a year later, but I'm also in Alaska and just got a FiST in August 2019 or so. I bought the Mountune FB3 package, and haven't put the intercooler on, and my RMM hasnt even shipped.
I ordered the package, and then it snowed. I want to utilize the 45 day free tuning but I can neither get traction in 3rd or 4th, nor do I have anywhere I can safely drive that fast now. Also, I'm stuck with 90 octane as the best I can get.
For kicks, i set up the gauges and have been watching the knock sensors and octane learn ratio, and it's all been fine on 90. OLR at -1.00. Occasional transitional knock...

I contacted Randy at Mountune about postponing the free tune session till next summer. I think it's going to cost me but I'm ok with that. My bad timing.
Also asked him about the 90, with often only 87 available. I also asked about the "Bad gas/panic mode." Here's his reply after I asked for clarification..

Bad fuel would mean the appropriate octane that is not good quality, as you will run into once in a while. This is not for octane levels that we do not support, as indicated on our site. It’s not for less than 91 octane. We don’t have official support for 90 octane.

You selected 91 octane on your order. You can try to use 90 octane, but I make no guarantees about the output. Just wanted to be clear about that.


His first reply:
I can usually offer a price break for repeat customers. Just talk to me first.

As for 90 or 87 octane, those are not supported officially. I'd use Stage 0 in those scenarios.


So, based on his reply I should used Cobb Stage 0, which I think is stock, but I don't know for sure. I've used higher settings and its drastically better, plus my observations show no learning for it to limit based on octane.

We'll see next summer I guess!


Btw, I plan to try autocrossing this car next year around AK, it should be a blast!
I would say that 90 octane *minimum* fuel will work fine on a 91 tune. You would just get the occasional negative correction and see blips in your OAR down into the -.9X range, but that is exactly why an ECU adjusts too, so it wouldn't *hurt* your car, you just wouldn't be able to tune for any more power, of course... I know you dropped a lot on that whole package, so I'd try to explain to Randy that you've spent a lot of money, so as part of the custom tuning for 45 days, just take his 91 tune and and make it a little less aggressive for you? Shoot, I would get some negative corrections turning 91 tune on 91 gas in California, gas quality is going to vary a bit anyway, being only 1 octane point off really shouldn't hurt. I think Randy will work with you once you explain a bit more that all you would expect is a tune that will run consistently for you at 90 octane. If the car can run safely from the factory with 87 octane in it, the adjustments available to a tuner should include a range of settings that would be perfect for 90 octane too, but since Cobb were the ones to Crack the ECU, they may not have included an adjustment range for anything less than 91 to be tuned...

But... already sounds like the base tunes is working fine if you only get a touch of knock at low engines speeds (normal on pump) and your OAR is holding steady at -1.00. Base tunes are by definition conservative to start with, you just likely won't be able to squeeze any more of it with revisions most likely, but just about any base/OTS 91 octane tune are likely to work the same way, and it's totally safe as long as you don't get knock and massive negative corrections during WOT.
 


Messages
10
Likes
7
Location
Fairbanks, AK
#10
You reiterated my thought exactly..I think it's safe, and there just might not be as much extra available. Hoping the OP sees this and either feels comfortable getting an OTS tune or feels validated that hes not going to blow it up with something like Cobb Stg 1.
And the car is a hoot to drive with boost coming in sooner!
 


OP
Pablo Pistoffo
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404
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Location
Anchorage
Thread Starter #11
You reiterated my thought exactly..I think it's safe, and there just might not be as much extra available. Hoping the OP sees this and either feels comfortable getting an OTS tune or feels validated that hes not going to blow it up with something like Cobb Stg 1.
And the car is a hoot to drive with boost coming in sooner!

Quick update- I've been running a Stratified tune since spring, and have been pretty happy- there is definitely an increase in power, and the rules for STH changed to allow intercoolers, so it was more than I was originally thinking I'd be getting. Even with the Quaife, I can break the front loose in some circumstances, so I've been thinking about going to a Dizzy tune, as the general consensus is that they have a bit more linear throttle response.
 


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