If 15 is better why 10?
03-03-2006, 08:10 PM
#2
6th Gear Member
Join Date: Sep 2005
Location:
Posts: 5,128
RE: If 15 is better why 10?
not neccessarily gas milage, but so you can run regular gas. You start advancing your timing then you need to run mid grade or premium. They set it at mild so you can run 87.
I do think you get a bit more mpg when you do that kinda tinkering, but you spend more on gas so it kinda cancels out
GEorge
I do think you get a bit more mpg when you do that kinda tinkering, but you spend more on gas so it kinda cancels out
GEorge
03-03-2006, 08:21 PM
#4
6th Gear Member
Join Date: Sep 2005
Location:
Posts: 5,128
RE: If 15 is better why 10?
they both do. Timing is the degrees before top dead center (BTDC) on the compression/power strokes that the spark occurs. The sooner it occurs, the slower the fuel needs to burn so you do not get pinging. Higher octane fuel burns slower than lower octane.
The compression factor has to do with heat. If you have higher compression, then more heat will make the gas want to explode more. Higher octane resists this effect.
That is why unless you either have high compresion or advanced timing, regular gas is fine.
This is about the extent of my knowledge on the octane thing. I know what cases you need which fuel, but as to the physics of it and why it is the way it is I'm not too sure.
My buddy has a 1972 chevy nova... 10.5 : 1 compression and his timing is wayyy advanced (he's always messing with it not sure what it is now) and he HAS to run premium. Running race gas makes the engine happy, usually he mixes a few gallons of 100 octane with the premium.
By the way what do you need to know for? Wantin to know what fuel to run in your car? what kinda car do you drive?
George
The compression factor has to do with heat. If you have higher compression, then more heat will make the gas want to explode more. Higher octane resists this effect.
That is why unless you either have high compresion or advanced timing, regular gas is fine.
This is about the extent of my knowledge on the octane thing. I know what cases you need which fuel, but as to the physics of it and why it is the way it is I'm not too sure.
My buddy has a 1972 chevy nova... 10.5 : 1 compression and his timing is wayyy advanced (he's always messing with it not sure what it is now) and he HAS to run premium. Running race gas makes the engine happy, usually he mixes a few gallons of 100 octane with the premium.
By the way what do you need to know for? Wantin to know what fuel to run in your car? what kinda car do you drive?
George
03-03-2006, 08:39 PM
#5
2nd Gear Member
Thread Starter
Join Date: Nov 2005
Location: Whitehall, Michigan
Posts: 170
RE: If 15 is better why 10?
I have an 04 GT 5 spd. cat back SLP ,intake K&N and after reading about the timing issue on MUSTANGS & FAST FORDS they set theirs at 15 degrees and got a real good power gain but did not say if they would have to up the octane. they just said at 16 degrees it started detonating so 15 was the highest they could go. So if I buy an adjuster for my car and set it at 15 would I still beable to run 87 octane?
ORIGINAL: monkeydude3
they both do. Timing is the degrees before top dead center (BTDC) on the compression/power strokes that the spark occurs. The sooner it occurs, the slower the fuel needs to burn so you do not get pinging. Higher octane fuel burns slower than lower octane.
The compression factor has to do with heat. If you have higher compression, then more heat will make the gas want to explode more. Higher octane resists this effect.
That is why unless you either have high compresion or advanced timing, regular gas is fine.
This is about the extent of my knowledge on the octane thing. I know what cases you need which fuel, but as to the physics of it and why it is the way it is I'm not too sure.
My buddy has a 1972 chevy nova... 10.5 : 1 compression and his timing is wayyy advanced (he's always messing with it not sure what it is now) and he HAS to run premium. Running race gas makes the engine happy, usually he mixes a few gallons of 100 octane with the premium.
By the way what do you need to know for? Wantin to know what fuel to run in your car? what kinda car do you drive?
George
they both do. Timing is the degrees before top dead center (BTDC) on the compression/power strokes that the spark occurs. The sooner it occurs, the slower the fuel needs to burn so you do not get pinging. Higher octane fuel burns slower than lower octane.
The compression factor has to do with heat. If you have higher compression, then more heat will make the gas want to explode more. Higher octane resists this effect.
That is why unless you either have high compresion or advanced timing, regular gas is fine.
This is about the extent of my knowledge on the octane thing. I know what cases you need which fuel, but as to the physics of it and why it is the way it is I'm not too sure.
My buddy has a 1972 chevy nova... 10.5 : 1 compression and his timing is wayyy advanced (he's always messing with it not sure what it is now) and he HAS to run premium. Running race gas makes the engine happy, usually he mixes a few gallons of 100 octane with the premium.
By the way what do you need to know for? Wantin to know what fuel to run in your car? what kinda car do you drive?
George
03-03-2006, 11:31 PM
#6
5th Gear Member
Join Date: Dec 2005
Location: Okla.
Posts: 2,060
RE: If 15 is better why 10?
ORIGINAL: ForeverFord
I have an 04 GT 5 spd. cat back SLP ,intake K&N and after reading about the timing issue on MUSTANGS & FAST FORDS they set theirs at 15 degrees and got a real good power gain but did not say if they would have to up the octane. they just said at 16 degrees it started detonating so 15 was the highest they could go. So if I buy an adjuster for my car and set it at 15 would I still beable to run 87 octane?
I have an 04 GT 5 spd. cat back SLP ,intake K&N and after reading about the timing issue on MUSTANGS & FAST FORDS they set theirs at 15 degrees and got a real good power gain but did not say if they would have to up the octane. they just said at 16 degrees it started detonating so 15 was the highest they could go. So if I buy an adjuster for my car and set it at 15 would I still beable to run 87 octane?
03-03-2006, 11:42 PM
#7
2nd Gear Member
Join Date: May 2005
Location:
Posts: 349
RE: If 15 is better why 10?
if you dont really know alot about timing it's better to let someone else do it, you could lose power if you advance it too far, and yes you do need a higher octane gas if your going to advance the timing.