GT4 - Unlocking the Power Potential!
07-03-2016, 08:34 PM
#751
To the best of my knowledge there have been no reports of any GT4s having oil or coolant temperature issues so I'm not sure an upgraded radiator would make that much of a difference here.
A modified engine might be more prone to pulling timing and might see higher combustion temps but not higher coolant or oil temps. This can be prevented by running a few gallons of 100 octane mixed with 93 or a booster like Torco Accelerator to keep combustion temps lower and reduce chances of timing being pulled.
A modified engine might be more prone to pulling timing and might see higher combustion temps but not higher coolant or oil temps. This can be prevented by running a few gallons of 100 octane mixed with 93 or a booster like Torco Accelerator to keep combustion temps lower and reduce chances of timing being pulled.
Removed the tune and limp mode problem have not reappeared in three track days after that in similar very hot temps.
Last edited by myBailey07; 07-03-2016 at 10:29 PM.
07-03-2016, 10:04 PM
#752
Rennlist Member
Never saw oil temps above mid 160's.
07-03-2016, 11:35 PM
#754
2 and both Cobb. Extreme conditions though, 95-100F track temps. And myBailey is the pretty much the fastest guy out there, so you have to be pushing hard. I don't want to have to drive my car with pink bunny shoes to make sure it can survive the weekend. What comes from the factory is very solid if that is what you care about. The other issue I had was that my car was slower with the tune somehow. I was getting pulled by other stock GT4s. A tune for a dyno-princess is different than a track car I guess.
That's exactly what I always do - mix in 2 gals of 100 octane per tank simply to protect against engine pulling time prematurely or a bad tank of gas, and some heat protection; however, car still went into limp mode with OTS Cobb tune (93 octane). Never saw oil temps above mid 160's. (Corrected: meant 260's)
Removed the tune and limp mode problem have not reappeared in three track days after that in similar very hot temps.
Removed the tune and limp mode problem have not reappeared in three track days after that in similar very hot temps.
07-03-2016, 11:46 PM
#755
Shake ran into other problems after that, but it was unrelated to the tune. My car was fine for the rest of the weekend and has been since leaving the stock tune on.
07-04-2016, 08:45 AM
#756
I know Cobb has a 100 octane tune. When I asked if it increases performance I was told that it was negligible and rather that it was done for those running on the track. They explained to me why it was beneficial, but I forget the specifics. Perhaps if you were running the 100 octane tune on a full tank of 100 on the track it would have eliminated the issue.
07-04-2016, 12:01 PM
#758
Please don't mention Donald Trump and Cobb Tuning in one breath 
07-04-2016, 12:53 PM
#759
I know Cobb has a 100 octane tune. When I asked if it increases performance I was told that it was negligible and rather that it was done for those running on the track. They explained to me why it was beneficial, but I forget the specifics. Perhaps if you were running the 100 octane tune on a full tank of 100 on the track it would have eliminated the issue.
Cobb also recommended that I mix in the 2 gals of 100 octane per tank of regular 93 for a bit of safety margin. I have done this for a long time on multiple cars here in the summer when it gets super hot. I am an engineer working in the refining industry and makes gas for a living and also know that when your car is optimally tuned for 93 octane it is not going to like any less. Not all gas is going to be 100% on spec and you can occasionally get some small variances or a bad batch. It is rare, but possible. Bumping the octane a point or two protects against the above and will cause no damage.
I think Shake said it best. We don't want to drive the car around on pink bunny slippers to get through a weekend and the stock setup has proven this. Running the stock tune with 93 octane + 2gals of 100 octane also made the problem go away and I was no slower in lap times.
I will stay stock from now on, as I still have driver mods to make and reliability is my number 1 consideration.
Please note that I am NOT saying to not mod the car at all. Various respectable shops like BGB/GMG etc. have power solutions in play, or working on it, with years of race experience. I am just saying that the more "race car" you turn your car into, the more time you're likely going to spend chasing that car and reliability becomes more of a consideration. Take that into consideration. I also think that going with solutions from one vendor such as BGB is wiser than slapping things from various vendors on your car and then having to chase various vendors if things do go wrong.
Anyway, just my thoughts, from now on my $'s go towards professional coaching.
07-04-2016, 12:55 PM
#760
I am pretty sure the stuck open TB is not cobb. It is my understanding that they were trying to offer assistance, but this problem is not tune related. I am not talking from first hand experience as I do not have TB.
07-04-2016, 01:07 PM
#761
Rennlist Member
I plan to tweak the suspension and leave the engine alone.
Has anyone recorded oil/water temps on their base car versus tuned over a 30 minutes session?
Has anyone recorded oil/water temps on their base car versus tuned over a 30 minutes session?
07-04-2016, 08:10 PM
#762
Yes, they do have a 100 octane tune, but I have no interest in running $10 gas for negligible power, especially not when I am using half a tank per session LOL. The benefit is basically that the higher the octane in a fuel, the slower it burns. This prevents premature ignition of the fuel, especially when ambient temperatures and/or the engine becomes very hot which can cause knocking. As a result, it also allows a tuner to then advance timing on the engine a bit to gain power, or otherwise it can prevent an engine from starting to pull timing to prevent knocking when the knock sensors start noticing it or it gets very hot. Cobb also recommended that I mix in the 2 gals of 100 octane per tank of regular 93 for a bit of safety margin. I have done this for a long time on multiple cars here in the summer when it gets super hot. I am an engineer working in the refining industry and makes gas for a living and also know that when your car is optimally tuned for 93 octane it is not going to like any less. Not all gas is going to be 100% on spec and you can occasionally get some small variances or a bad batch. It is rare, but possible. Bumping the octane a point or two protects against the above and will cause no damage. I think Shake said it best. We don't want to drive the car around on pink bunny slippers to get through a weekend and the stock setup has proven this. Running the stock tune with 93 octane + 2gals of 100 octane also made the problem go away and I was no slower in lap times. I will stay stock from now on, as I still have driver mods to make and reliability is my number 1 consideration. Please note that I am NOT saying to not mod the car at all. Various respectable shops like BGB/GMG etc. have power solutions in play, or working on it, with years of race experience. I am just saying that the more "race car" you turn your car into, the more time you're likely going to spend chasing that car and reliability becomes more of a consideration. Take that into consideration. I also think that going with solutions from one vendor such as BGB is wiser than slapping things from various vendors on your car and then having to chase various vendors if things do go wrong. Anyway, just my thoughts, from now on my $'s go towards professional coaching.
I'm having the IPD Plenum and 82mm TB installed by Fabspeed this Wednesday. They're also doing their sport headers, exhaust and custom protune on the car (using the Cobb Accessport). I'm hoping that by having everything done at once, with the tune done specifically for my car, future issues will be avoided. It's going to be around 95-100 degrees on Wednesday. I'm running mostly on the street, though, so even in the heat I'll probably never see the engine temps you were seeing on the track.
As an aside, regarding the throttle body, I'm having Fabspeed update the ECU for it with the Porsche PIWIS before the protune so that it won't throw codes. I know this may be seen as redundant, as Cobb has apparently been able to access this part of the ECU programming. My logic is twofold. First, my dealer doesn't like to see cars come in for service with a tune in place. By coding the ECU with the PIWIS the TB won't throw codes and should function without issue. Second, if I do have issues with the tune, I can remove it and still be able to take advantage of the upgrades without throwing codes. Being that I went with catted headers, I shouldn't have to worry about CELs.
07-05-2016, 11:19 AM
#764
really hard to get any real info as every one with a tune seems to be having issues !!
but put a stock map back on and every one is happy !
we really need to know if a Tune and a TB will work 100% as no one is saying this yet ! or giving any real 100% YES
07-05-2016, 11:19 AM
#765
As an aside, regarding the throttle body, I'm having Fabspeed update the ECU for it with the Porsche PIWIS before the protune so that it won't throw codes. I know this may be seen as redundant, as Cobb has apparently been able to access this part of the ECU programming. My logic is twofold. First, my dealer doesn't like to see cars come in for service with a tune in place. By coding the ECU with the PIWIS the TB won't throw codes and should function without issue. Second, if I do have issues with the tune, I can remove it and still be able to take advantage of the upgrades without throwing codes. Being that I went with catted headers, I shouldn't have to worry about CELs.
That would be great as you would only need to flash the ECU back with the stock maps when taking the car for service but I'm afraid you will still get CELs if running on stock maps...anyway, it doesn't hurt to do any updated to the ECU + the TB calibration if that's available.