SCT question

Discussion in '2005 - 2009 Specific Tech' started by ThatOneFastKid, Jun 28, 2006.

  1. ThatOneFastKid New Member

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    i have an SCT2 tuner and i havn't installed it yet. but i am going to tune the car for 91 octane fuel, is it bad if i do it when i have almost a full tank of 87 octane still left in it?
  2. DarrinB New Member

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    Make sure you back out of the throttle if and as soon as you hear any pinging. With knock sensors you might not hear any at all, but don't overdo it regardless. As long as you stay out of the throttle and don't have a power adder then its probably ok to do it and run the gas out.
    Darrin
  3. bigcat start with the upper hole, and if more traction is

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    its just a tank of fuel, wait a few days to be safe. a few days wont kill you, no matter how excited you are.
  4. red05bullitgt New Member

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    I guess you'll be ok, if you follow Darrin's advice..However, as Bigcat mentioned..why not just wait, a few more days ? or at least wait, until your close to running out of 87 before installing, your SCT 91 oct tune..It's one thing to be excited, but it's much better to be safe, than sorry..After all you've waited this long, right ?? so what's a few more days going to hurt ?? Anyway, if I were you, I'd much rather wait, then take a possible risk, of damaging your pistons, due to detonation problems..:shrug:
  5. ks44142 Member

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    I have the SCT 2 w/ the 91 program loaded and had I about 1/2 a tank of 87 when I got mine. The guy at the place where I got mine said to run it down to about 1 gallon of 87 being left then fill will 91 and retune. I'd wait... as much as it will feel like it's taking forever it is well worth it to not have any wories that you might be messing your ride up... cause you know you'll want to get on it to see what/how it has change... just my 2 cents good luck!
  6. anthony05gt New Member

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    Wait! All it takes is a little detonation to burn through the 1/8" thick top of the 3-valve engine's pistons. Run it down to half and top it off with 93 before the reflash.
  7. mhanksii New Member

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    I would have to agree with everyone else, WAIT! It would be a shame to have a hole in a piston over a tank of gas, besides with your foot on the floor your only getting something like 3-4miles to the gallon anyway. I say it's time to go to the track or some wide open highway
  8. killertomato New Member

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    What does everyone do when they need to go back to the stock tune when taking a there GT into the shop with a tank of 91-93?
  9. Saleen-wana-be New Member

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    running with higher then you need cant hurt anything but running with to low can. If you need to put the stock tune in, just put it in, keep the 93 in the car so once you get it back you can just put the new tune back in.
  10. DarrinB New Member

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    Yeah, I don't see why you want to do it either, but I just answered your question accurately without telling you what I think you should do. The fact is that many people do exactly what you are talking about. They shouldn't, but you can't stop them.
    With that said, on a stock engine with knock sensors and no power adder then the liklihood of breaking ring lands or burning up valves just really isn't very big. You would flat be amazed how many vehicles come to me that are detonating and they drive them like that every single day and have been for years. A lot of them don't have knock sensors, and I don't know if your vehicle does either.
    Now, if there is a power adder involved then don't do it under any circumstances. That is a sure fire way to break your engine.
    Again, should you do it? No. Are you going to? Its probably very likely, regardless of people telling you not to. Nothing against you personally, but I just know what really happens in these situations. I gained that perspective on exactly this subject from a lot of experience and I just told you how to drive it that way until you get the proper fuel in there. I have to tell people that often. I get the " I know you said not to, but I went ahead and put the premium file in already and it knocks really bad. Did I hurt anything?" phone call way too often.
    Remember, detonation is BAD.
    Darrin
  11. krang00 Founding Member

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    If you are in a hurry, just drive the car around until you run out of gas .... or ciphon it :)
  12. MARKCORE New Member

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    Can you turn off the O2's wtih the SCT?
  13. bigcat start with the upper hole, and if more traction is

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    yes, the rear O2s can be turned of with the SCT.
  14. MARKCORE New Member

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    Cool thanks man. I was reading about it but never found anything that says just that as the Predator discrption does.

    I've also been told that everyone is using the SCT vs the Predator(diablo) for the 05-06 GT's. Any truth to this? and if so Why??
  15. bigcat start with the upper hole, and if more traction is

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    many people prefer the SCT over the diablosport. IMO SCT has the edge in tuning the S197s. word of mouth gets out, and people purchase the tuner that gets more positive feedback from users.

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