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Unichip....will higher octane fuel increase its performance ability?

4681 Views 34 Replies 17 Participants Last post by  spydertoph
So after 2 years of debating if its worth paying between $400 and $500 for a Unichip I broke down and bought one. I already had the AEM CAI, TM Duals, Che header and a Che catless downpipe so I figured I might as well complete the circuit. I got my Unichip in the mail the other day and hooked it up and really didn't feel much of a difference driving around town. The seller suggested using higher octane gasoline with the chip....89 or 91, I have always used 87 since I bought my MR2 back in 2007. Will upgrading to 89 or 91 really help improve performance in my Unichip and my MR2? With gas being so expensive these days every penny counts. On a side note after plugging in my Unichip I noticed that my check engine light actually went off....it had been on ever since I installed the Che catless downpipe. Is that normal? Thanks for any advice or info!!
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So after 2 years of debating if its worth paying between $400 and $500 for a Unichip I broke down and bought one. I already had the AEM CAI, TM Duals, Che header and a Che catless downpipe so I figured I might as well complete the circuit. I got my Unichip in the mail the other day and hooked it up and really didn't feel much of a difference driving around town. The seller suggested using higher octane gasoline with the chip....89 or 91, I have always used 87 since I bought my MR2 back in 2007. Will upgrading to 89 or 91 really help improve performance in my Unichip and my MR2? With gas being so expensive these days every penny counts. On a side note after plugging in my Unichip I noticed that my check engine light actually went off....it had been on ever since I installed the Che catless downpipe. Is that normal? Thanks for any advice or info!!
Most of the Unichip tunes are programmed for higher octane fuel. The manual that came with mine says it was 87 octane on one map, and 93 on the other.

The only time you will gain power with higher octane is when the car is programmed to use it- more timing advance, etc. If the car is tuned to use it, and you're still using 87, there's a chance the knock sensor is retarding timing back to the point where you may actually have reduced power with your unichip.

My advice is to figure out exactly what the chip is tuned for.
Firstly you need to understand what Octane means, a higher number means the fuel is more resistant to explosion, so if your engine is designed and tuned to run on 87, running 92 will do you no good. Basically engines are tuned so that they will not have any knock or detonation at the fuel they're tuned for, you can tune for more power with a higher octane because it will handle higher pressure/temperature without blowing up at the wrong time in simple terms. If the unichip were tuned to take advantage of a higher octane you'd probably get a check engine light.

This brings me to the second point, if your light is on, you need to address the issue, use a code reader, find out what is going on, and take care of your engine. Driving around with the light on is stupid and reckless, so unless you've got some cash saved away for a 2zz and you're just really wanting your engine to blow up I recommend taking better care of it. Trust me I'm on my 4th engine.

I don't know anything about the unichip myself though so understand you may have to call them and find out what you've got, from what I understand different tunes are available so you may be able to get more out of it by having it set up for your mods and running a higher octane.

-Spargo
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yep mine is mapped for 91 octane cali cat piss works fantastic noticable gains but i have mine disabled cause of the constant hosing we are experiencing at the pump need some newt 250 gas lol :lol:
Interesting thread....so, if running stock, what octane?

Rick
87 with a stock computer
Yes to this.
87 with a stock computer
^^^ Godamnitsomuch.

Anyway.

Most out of the box Unichips will at least have an A/B map switch.

A is for 87, gave me some increased HP (sensation) because the out of chip expects aftermarket exhaust.

B is for higher octane and gives a very noticeable gain in but HP (I feel torque too). The fuel efficiency changes (B vs. A) are not detectable. I feel that miles per. dollar are less in the city, equal on the highway, and I did many daily 100mile commutes. Don't fret about the price of premium vs. regular, the more gas prices go up, the closer in price they become.

I recommend you reset your ECU when you plug in the unichip or switch switch octanes.

Regarding the $400-$500 investment: don't forget you can sell it to the next guy when you are done.
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I use premium because it's cleaner. :lol:
Trust me I'm on my 4th engine.

I don't know anything about the unichip myself
Seriously, I cannot understand why you weigh into some of these discussions.
I use premium because it's cleaner. :lol:
Good one Dev! :lol:

I would suggest a tour for everyone of our nasty refineries. All vehicles operated by the company in one such "unnamed" nasty refinery have a huge added fuel filter.

Following the tour, most people would be at the local parts store buying an inline fuel filter to add to their car.

On a sad note, I can no longer find fuel that has no ethanol, so gas mileage has gone to sheet on all of our vehicles.

Ethanol is like putting cracker crumbs in meatloaf. Makes 5 gallons out of 4, but you can only travel the distance of 4 gallons, however you have to pay for 5 gallons. Science at work. No offence intended to our friends who are scientists, the oil companies would've used water, but couldn't get it to stay mixed!

Bend over America.
I have a unichip in mine tuned for 87/91 depending on which map is selected. I have never used the lower octane map since installing mine but with the higher octane map selected I can tell a positive difference with the unichip, it's not a night and day type difference but it can be felt more than the other mod's done ie intake, exhaust etc. It's most noticeable to me when getting on a highway at wot.
Run PFC everybody :lol:
Love both mine

my first one came with my Tk.com Kit
and my 2nd for my MR2 2zz i got for 550$
Seriously, I cannot understand why you weigh into some of these discussions.
+1 :lol:

Why are you guys talking about cheaper gas when your putting a part for more performance. That just doesn't make sense. Its like saying you turbo'd your car but then you drive really slow so you don't eat up all the gas boosting. :lol: You know what they say.. if you can't afford to play buy a god damn Hyundai.
Part of the problem is the red LED light that is supposed to turn on when you toggle back and forth isn't lighting up, so I can't tell if I am on Map A or Map B. I'm going to double check my connections in the morning.

I'm down to about an 1/8 of a tank of gas so I will fill it up with the premium 91 or 93 octane and see if that makes a difference. I just won $3 on a Mega Millions ticket so I will donate those profits to cover the cost of the premium gasoline.

About the check engine light...the Che catless DP confuses the 02 sensors thats causing the CEL. I check it every now and again just to make sure.

Today while driving some back roads I thought I felt a nibble of power gain, especially in 2nd and 3rd gears. Maybe the Unichip is learning?
Seriously, I cannot understand why you weigh into some of these discussions.
Well he clearly didn't know what octane meant so I told him, I'm glad you're here to review my posts though :wub:

-Spargo
Well he clearly didn't know what octane meant so I told him, I'm glad you're here to review my posts though :wub:

-Spargo
Your post was reviewed and condensed to the most useful information: You are on your fourth engine, and you state you know nothing about unichip. So the message is "Don't listen to this guy when he's giving technical advice."
Run PFC everybody :lol:
Love both mine

my first one came with my Tk.com Kit
and my 2nd for my MR2 2zz i got for 550$
excelent choice

why use a stinky piggyback when you can go completely fully programmable
excelent choice

why use a stinky piggyback when you can go completely fully programmable
I did it because SMT and PFC don't mix.
Part of the problem is the red LED light that is supposed to turn on when you toggle back and forth isn't lighting up, so I can't tell if I am on Map A or Map B. I'm going to double check my connections in the morning.
No sure witch model is yours. Maybe the instructions will help you guess which way to put the rocker switch. Heck, mine doesn't have a LED (siimilar to below image) so I assume it's designed so I'd guess correct: The switch says "A/B" so I assume I depress the right side to get B:



I did it because SMT and PFC don't mix.
Same here.
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