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87 octane in a stock 1g AWD?

DSMopar

10+ Year Contributor
610
13
Oct 6, 2007
Vista, California
Anyone do this? It doesn't specifically say 91 or high grade on the dash like the 2g's, it's running less compression and less boost than a 2g, so why not? Doesn't feel like it's making enough power to warrant 91 :rolleyes:.
 

97 4G63

5+ Year Contributor
1,040
4
Mar 27, 2006
RALEIGH, North_Carolina
Yeah it may not say that but i'm sure every turbo car needs the higher octane ..
But i'm sure you can get away whit it for a year or so till your car starts to have problems..
 

tqmx1

5+ Year Contributor
668
3
Jan 17, 2007
Sacramento, California
Been running 87Oct in our 91TSI for about the last 100k. Have not knocked a hole through a piston yet. Total milage 186kROFL
 

toyotaturbo

5+ Year Contributor
389
3
Apr 10, 2006
Aberdeen, Maryland
Don't run 87 octane gas!!! You will knock like crazy and your head gasket will ultimately fail! Hopefully your entire head won't fail! I've seen terrible engine damage from running cheap gas. I wouldn't do it if I were you. Don't ever go below the manufacturer's recommendations.
 

talon187

5+ Year Contributor
1,046
0
Feb 11, 2003
torrington, Connecticut
yeah when i first got my awd i picked it up and it had 87 in it valvues were pinging under 8lbs of boost not good at leat run 91 i run 93 in mine but im built and all tuned for 93
 

tkelly27

5+ Year Contributor
1,712
26
Mar 11, 2007
Gresham, Oregon
... well, you could waste your money on 91, or you could get a logger and watch your knock counts. If you don't go into boost, you're less likely to knock with the turbo car than if you had the NA version which has no octane recommendation. If you do go into boost, it's not as if the factory didn't set up the computer to be able to run on crappy gas. If the engine blew up every time someone put 87 in their tank there wouldn't be many DSMs left.

I've run 15psi without audible knock, but I wasn't running a logger so I can't tell you for sure if it was actually knocking or not. Everything looked hunky dory (plugs, head, pistons, gasket) after 3 months of that when the timing belt let go. Your experiences may vary, and the only way to know is to have a logger and figure it out for yourself.
 

tunethis

10+ Year Contributor
882
7
Jan 29, 2008
GVL, Florida
Please pay the extra cents for the higher octane. It's worth it.
 

JayRolla

5+ Year Contributor
5,630
32
Feb 23, 2006
Colorado Spring, Colorado
Valves could also burn up. I have a 93 TSi and it says right on the dash premium fuel only. All forced induction cars need to run the highest octane available.
 

SlickGSX

Proven Member
137
0
Aug 14, 2006
Chicago, Illinois
The stock ecu's have "octane value" or knock counts stored into its memory so if you drive around on 87 and get some occasional knocking your ecu will pull timing and stay in that mode until you put miles back on with 91(crappy Cali gas).
 

tqmx1

5+ Year Contributor
668
3
Jan 17, 2007
Sacramento, California
Valves could also burn up. I have a 93 TSi and it says right on the dash premium fuel only. All forced induction cars need to run the highest octane available.

Jay, But the 92.5 and up they went with the 7bolt = higher CR. The 6bolts running stock boost+timing are happy as clams on lowtest.

Now if you want to crank up the boost and go crazy then you can start paying the extra 20c+ per gallon.

To each His or Her own driving style.
 

Mr Peepers

DSM Wiseman
1,272
27
Oct 16, 2005
Janesville, Wisconsin
I can't say for sure, but you are forgetting that 1g's have an extremely aggressive timing curve compared to 2gs. If you stay out of boost you won't have a problem, but then what's the point?

Get a logger and see for yourself.

Jay, But the 92.5 and up they went with the 7bolt = higher CR. The 6bolts running stock boost+timing are happy as clams on lowtest.

Now if you want to crank up the boost and go crazy then you can start paying the extra 20c+ per gallon.

To each His or Her own driving style.

Just because it's a 7bolt doesn't mean it has 8.5:1 compression. All 1g's have 7.8:1.
 

JayRolla

5+ Year Contributor
5,630
32
Feb 23, 2006
Colorado Spring, Colorado
Jay, But the 92.5 and up they went with the 7bolt = higher CR. The 6bolts running stock boost+timing are happy as clams on lowtest.

Now if you want to crank up the boost and go crazy then you can start paying the extra 20c+ per gallon.

To each His or Her own driving style.

90-94's had the lower compression. I think some later 94's may have come with the higher compression pistons but not many. I bought a 89 Turbo Shadow for real cheap because they thought it had a bad injector. It would not boost at all. I filled up with premium fuel and about 5 miles later it came back to life. I asked them and they said they ran 87 since it was new and started acting up about 10 years later. It took a long time to start acting up, but it did.
 

tlikethedrink

5+ Year Contributor
362
90
Sep 11, 2007
ABQ, New_Mexico
IMO its worth not worring and just shelling out the extra 2 bucks. i mean come on, what are you gonna do with those 2 bucks anyways. you dont need the xtra burgers from the dollar menu...LOL
 

xveganxcowboyx

5+ Year Contributor
1,525
23
May 15, 2005
St. Paul, Minnesota
I've run low octane gas (accidently) in the past. My experience was shitty performance, and a loss in mileage. My guess is the engine saw knock several times, pulled timing which hindered performance and cost me some mileage. With the loss in mileage I would have spent the same or less just forking over the extra $0.20 per gallon for premium. For the record, this was a completely stock car at ~120,000 miles.

In my opinion, it's a short sighted and irresponsible decision to try to save a few cents now at the potential cost of your engine later.

Also, I'm pretty sure the owners manual specifies 91 octane, even if it's not written on the dash.
 

Bud92gsx

Welcome Wagon
22,926
307
Jan 16, 2008
Wisconsin, Wisconsin
Ya no doubt I had like cheap stuff in there ### I wasnt driving my car. Well I ran it dry and put the highest octane shell gas in there and she runs good now. I miss the higher octane! Stay with it!
 

tqmx1

5+ Year Contributor
668
3
Jan 17, 2007
Sacramento, California
I've run low octane gas (accidently) in the past. My experience was shitty performance, and a loss in mileage. My guess is the engine saw knock several times, pulled timing which hindered performance and cost me some mileage. With the loss in mileage I would have spent the same or less just forking over the extra $0.20 per gallon for premium. For the record, this was a completely stock car at ~120,000 miles.

In my opinion, it's a short sighted and irresponsible decision to try to save a few cents now at the potential cost of your engine later.

Also, I'm pretty sure the owners manual specifies 91 octane, even if it's not written on the dash.

OK 90 DSM owners manual.
[ Cars Equiped with turbocharged engine:
Your car will operate satisfactorily on premium unleaded gasoline having a minimum octain rating of 91, (R+M)/2. These designations are compaired to 95RON (Research Octane Number)

However, you may use unleaded gasoline with an octane rating of at least 87 (91RON)

If prolonged heavy engine knocking (audible pinging) occurs on your car, consult your dealer.]

So as I was saying it depends on how you drive it what you can get away with. For racing HELL YES the higher the better For the wife 100miles freeway a day the engine is happy on 87
 

voodoogsx

5+ Year Contributor
312
9
Jun 2, 2004
Sherman Oaks, California
One of the reasons why I've considered going to something slightly lower than 91 myself....
Mind you, this is not the norm and most places around the area are 30 cents less...but damn...

I honestly don't know how people go to this place when one block away you can save.....maybe they put flakes of gold in there like goldschlagger???

Also note the race gas sign...price on the pump is8.50 I beleive.....I paid 4 something at the track....yeesh

Good ole LA, ca....wooot :notgood:
 

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Executionerhk

Proven Member
130
0
Feb 21, 2008
Topeka, Kansas
because my car runs 13 mpg... so i start putting 87 in the car...
after I found out what is wrong and fix it, maybe I will put 91 back...

but guys... 91 is nothing in europe...
the cheapest gas in Austria is 91... and then 95 and then 97...
haha~ funny that we have 91 top around towns in USA!!
 

PIMking

10+ Year Contributor
2,782
3
Jan 29, 2008
tuscaloosa, Alabama
God Forbid that 91 would be the cheapest gas here in the us.

I use majority of 93 octane but if I am just going to run up to my hockey games which is 30 miles away I will sometimes put cheaper gas in because I know that I will burn it all by the time I get home.
 

tqmx1

5+ Year Contributor
668
3
Jan 17, 2007
Sacramento, California
I think he was thinking 91RON what works out to 87.
 

Hmong_1G

Probationary Member
22
0
Feb 16, 2008
City of Trees-NORCAL, California
I know I responded to a similar thread in DSMTALK.COM. SO here is the exact run down.


The main purpose of running higher octane is not the rating but the flash point. Go research on it. Octane boosters don't do anything more than a cleaning additive. 87 octane has a lower flash point then 91. Regardless of location. Different seasons see different octane values. Colder areas will receive lower octane value and flash point. While hotter areas will receive higher octane values and flash point. Its best to run 91, since it will be more efficient and economical in a hotter running vehicle (turbo). (FLASH POINT- A point of temp when fuel starts to evap)
 

hypnoticpimp

Proven Member
226
1
Sep 14, 2005
hawthorne, California
One of the reasons why I've considered going to something slightly lower than 91 myself....
Mind you, this is not the norm and most places around the area are 30 cents less...but damn...

I honestly don't know how people go to this place when one block away you can save.....maybe they put flakes of gold in there like goldschlagger???

Also note the race gas sign...price on the pump is8.50 I beleive.....I paid 4 something at the track....yeesh

Good ole LA, ca....wooot :notgood:

Where is that gas station located at? I'm sure by racing fuel they mean 100 octane right?
 

kapllia

Probationary Member
2
0
Nov 2, 2007
daly city, California
i ran 87 i pay for it , now getting rebuilt because i try to save
few dollar ,i have hole inside piston :nono:
 

tqmx1

5+ Year Contributor
668
3
Jan 17, 2007
Sacramento, California
i ran 87 i pay for it , now getting rebuilt because i try to save
few dollar ,i have hole inside piston :nono:

Man after reading your engines bio (4g64 big turbo yada yada yada) trying to make it run on 91 was no easy job let alone LOLey 87.

I have been talking mostly stock engines (min mods).

As I said before if you are pounding the PISS out of it one a daly bases the highest Oct. you can find + some ADI wont hurt.
 
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