knocks on 87, so let's use 91!
10-04-2006, 03:37 PM
#1
1st Gear Member
Thread Starter
Join Date: Jul 2006
Location:
Posts: 91
knocks on 87, so let's use 91!
After all the talk on how our (stock) S197s ping on 87 gas, why not use 91 octane? I know it's more expensive but beyond that, higher octane should cure the pinging. And think about this: Since our ECUs retard timing when pinging is detected, we're losing HP on 87 gas. If we used 91 and eliminated the pinging then the ECU would allow all available timing advance.
And I've been reading on the SCT company site. Ryan, one of the techs there, states that they have seen an increase in HP on stock-tuned s197 GTs using premium fuel alone. That makes sense if everyone is pinging on 87. I know that on newer cars normally higher octanes do nothing (even can lose HP) if there are no knock sensors to control timing advance but our cars appear to be "over-advanced" for 87 octane.
thoughts?
And I've been reading on the SCT company site. Ryan, one of the techs there, states that they have seen an increase in HP on stock-tuned s197 GTs using premium fuel alone. That makes sense if everyone is pinging on 87. I know that on newer cars normally higher octanes do nothing (even can lose HP) if there are no knock sensors to control timing advance but our cars appear to be "over-advanced" for 87 octane.
thoughts?
10-05-2006, 03:25 PM
#6
4th Gear Member
Join Date: Jun 2006
Location: Maryland
Posts: 1,284
RE: knocks on 87, so let's use 91!
I dunno, I never had problems when my car was stock running 87.
+1 Was not stock long though.
Also no 91 in my area 87---89---93 only Always better to step up a level when you have issues like that as some stations are rated a little lower than what they say (bastards!) I ran 93 Oct gas on 91 tune for a while before going 93/93.
10-05-2006, 06:36 PM
#7
RE: knocks on 87, so let's use 91!
The main problem I have read on using 91 or 93 with out the tune is the excess carbon buildup on the plugs, making them damn near impossible and dangerous to pull, I have not expreianced this yet, but have read it many times. If you car is pinging on 87 and is tuned for 87, try a diff brand of gas, if that doesnt work take her back to the stealer and have them reflash it.
10-05-2006, 06:42 PM
#8
5th Gear Member
Join Date: Dec 2004
Location: Small walk way by big walk way
Posts: 4,717
RE: knocks on 87, so let's use 91!
I actually feel sorry for people who have the 91 tune because the 93 tune is a homerun. I've tried both and there is a big difference.
ORIGINAL: RCT06GT
All I have to say is 91 octane tune! Try it out and you wont be dissapointed.
All I have to say is 91 octane tune! Try it out and you wont be dissapointed.
10-05-2006, 07:56 PM
#9
6th Gear Member
Join Date: Sep 2006
Location: Gainesville, FL
Posts: 11,278
RE: knocks on 87, so let's use 91!
There's a noticeable difference, but I don't think i'd call it big. First gear is a little unrulely with the 93 tune, you really have to step on the gas or it will get angry.
ORIGINAL: Daniel60
I actually feel sorry for people who have the 91 tune because the 93 tune is a homerun. I've tried both and there is a big difference.
I actually feel sorry for people who have the 91 tune because the 93 tune is a homerun. I've tried both and there is a big difference.
ORIGINAL: RCT06GT
All I have to say is 91 octane tune! Try it out and you wont be dissapointed.
All I have to say is 91 octane tune! Try it out and you wont be dissapointed.
10-05-2006, 08:52 PM
#10
5th Gear Member
Join Date: Dec 2004
Location: Small walk way by big walk way
Posts: 4,717
RE: knocks on 87, so let's use 91!
My car just reacts to the 93 tune bigtime that's all I'm going to say.
ORIGINAL: moosestang
There's a noticeable difference, but I don't think i'd call it big. First gear is a little unrulely with the 93 tune, you really have to step on the gas or it will get angry.
There's a noticeable difference, but I don't think i'd call it big. First gear is a little unrulely with the 93 tune, you really have to step on the gas or it will get angry.
ORIGINAL: Daniel60
I actually feel sorry for people who have the 91 tune because the 93 tune is a homerun. I've tried both and there is a big difference.
I actually feel sorry for people who have the 91 tune because the 93 tune is a homerun. I've tried both and there is a big difference.
ORIGINAL: RCT06GT
All I have to say is 91 octane tune! Try it out and you wont be dissapointed.
All I have to say is 91 octane tune! Try it out and you wont be dissapointed.