What octane gas do you run in your TGP???

[dbtk2]

Just wondering if everyone here runs premium or what.  Over the amount of time that I've had my STE, when I had the turbo Lumina, and when I drive my dads TGP, I have scanned each of them and noticed that none of them ever saw any KR under WOT with 93 octane.  Of course they all had chips in them, with the stock chip this might be a different story.  In the Lumina I dropped the gas to 89 octane once just to see and it got no KR until it shifted into 3rd gear where it would start to develop 1-2 degrees.  Other than that I have always run 93+ octane in all of them.

Except, I have been scanning the STE a bit over the past few days and it seemed impossible to make it see KR.  It seems that the topgun 160 chip is not very aggressive with timing at all, and with my cammed and 3100 topend setup, the T25 just doesn't keep up and at the boost levels you can run with the topgun chip (pretty much 12psi or less otherwise it pulls mad timing) and it just can't move enough air to get it hot enough to get KR.  So today it was pretty much completely out of gas.  I drove by the gas station and 2.14 for 87 octane sounded like not too bad of a price to me.  I haven't put regular gas in a car for like 9+ months.  So, I filled the tank up to the top with 87 octane.  I think it was 14.7 gallons IIRC. 

I went out and scanned the car and I was letting the chip control the boost, and it seemed to be right around 10-11psi the whole time.  The car gets no KR at all still unless I really really try to make it get some.  If I take the tv cable off so the tranny stays in 3rd gear and go WOT from a 30mph roll then it will generate 1-2 degrees that goes away once its not under so much load anymore, thats pretty much the only way I could get it to get KR.  I was playing with the throttle in normal cruising trying to generate KR and couldn't get it to get any.  Next I'm going to look and see just where the chip starts pulling timing and probably run just a hair less boost than that with a manual boost controller and see where that gets me.  The car seems to be running healthy, but since I've been driving a 12 second capable car daily for the last month, this car just doesn't seem to impress me much.

Anyways, I was impressed by what I found and will be doing a bit more testing on this.  Basically what this tells me is that my chip is WAY too conservative for my setup and I need more timing and/or a bigger turbo.  For now, I'm enjoying the $.20 a gallon I'm saving, but I do still need to see if there is a gas mileage difference with the lower octane.  My injector pulse widths are also approacing 30 so I think its time for an upgrade since 23 is maxxed.  :icon_redface:  The car does seem to be running a bit lean at WOT.

Anyways, I figured I'd see if any of you guys are doing anything like this (running regular gas), or if you all are pretty much running premium...

Shawn

[Invasion1]

91 V-Power Shell most of the time here at home....

If im in a bigger city i use 94 Ultra Sunoco cause we don't have any Sunoco's here in town

[LukeZ34]

91... always.

[R Dubya]

I have never run anything besides 93 octane in either of my TGP's.  My brother used to run 87 in his Passat 1.8T and he didn't know any better, finally I mentioned it to him, he read the sticker by the filler neck and on the dashboard  :icon_rolleyes: and started running at least 91.  You could actually hear the turbo spooling after that..

[TGPilot]

I have done a similar test and as soon as I drop below 91 Octane (85 is minimum here with 92 max at the pump) I see GOBS of knock! I am running 14 PSI...now if I torque it down to 11-12 PSI I can run 89 Octane with minimal knock and 87 we will not discuss! ;)

Now I did run a tank of Ethanol (106 rated) with the injectors maxed out to not fry the pistons it was so lean. I saw ZERO knock in any load range at 14 psi, but that is the same with pump 91 Octane. I need to play some with the big turbo with max boost on the built engine (22-25 PSI and Ethanol) this winter. She may end up being a Dyno Queen if I can not find an alternative to the stock 282...but it will be fun non the less! ;) :laugh:

[mfewtrail]

I always run 93 octane/premium in the TGP.

[GOT2B GM]

Sunoco or GTO Ultra 94 for me, unless I'm somewhere that its not available then I get 91 octane.

[dbtk2]

Has anyone else other than TGPilot scanned to see what their KR level is, to see if they are able to run lower octane?  I know its not really a big deal, I've never worried about it before and just always used 93+ octane, but knowing that I don't have to is a nice peace of mind. 

[Invasion1]

Mine does not like 87 at all....

Had to get it once as all the premium was gone.

ran like a bag of crap untill i got 91 to fill the rest of the tank

[GangstGP]

If you ever get that regular gas again, just dump in some paint thinner in there.

Xylene or toluene. it will bring back up the octane level.

but you got to add 3 to 6 oz.  tranny fluid/marvel mystery oil or lucas fuel injector cleaner to avoid SERIOUS engine AND fuel system damage . :icon_razz:  ;)

[mfewtrail]

Has anyone else other than TGPilot scanned to see what their KR level is, to see if they are able to run lower octane?  I know its not really a big deal, I've never worried about it before and just always used 93+ octane, but knowing that I don't have to is a nice peace of mind. 

I haven't scanned the TGP, but I will soon. I pretty much know I probably need 93 at a minimum if I want to romp on the gas anytime from spring to early fall here w/ our weather(very hot & really humid...feels like the car loses about 50hp in those conditions :laugh:).

[TGP Nick]

I always run 92-93 octane in mine.  And whenever possible I run it with NO ETHANOL.

[TGPilot]

If you ever get that regular gas again, just dump in some paint thinner in there.

Xylene or toluene. it will bring back up the octane level.

DO THIS AT YOUR OWN RISK! TGPFORUMS DOES NOT AGREE WITH ALL STATEMENTS MADE BY IT'S MEMBERS! EXTREME DAMAGE MAY HAPPEN TO YOUR MOTOR AND FUEL SYSTEM IF YOU DO NOT MIX THIS PROPERLY!

[kuntzie]

94.... or better

[twinturbosedan]

i always use 91 (highest available here).  i'm seeing 7-10* KR at WOT.  i don't have a boost gauge at the moment but i think it's around 12psi.  i scan with OTC 4000E.  it might be false knock i'm not sure...i can't hear it pinging like i can with my GTS.  while swapping the turbo the other day i found a few things that were loose (bellhousing bolt, downpipe bracket etc) so that might have been the cause....hopefully.