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I dont think your stupid or misinformed, and your car obviously is in good shape to survive for 200K miles. It just dosent make sense to degrade performance, and have knocking and pinging, just to save a few dollars here and there. I'd rather put the good stuff in my tank and know that I can run my car hard, have maximum engine performance without any possible ill effects. You should dyno your car sometime, with your preferred 87 octane, and see what kind of numbers it puts out and how much pinging there is under load. It would be interesting for comparison sake especially sice you claim to maintain it very well. 
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Originally posted by '99 Contour SE:
What have i started lol!
You started a ruckus. Most of this thread is lame.
You can run low octane fuel in your SVT, period.
Will it cause knock? Maybe. The chances are a hell of a lot better with low octane fuel.
Remember, the first thing that will happen when using poor grade of fuel is pre-ignition, or pinging depending on the load, outside temperature and timing.
Pinging isn't likely to damage the surfaces of the type of piston that we have in our motor.
This pinging will always precede full blown engine knock. The engine knock is what happens after preignition when the flame front (and overall cylinder pressure) gets high enough to slap the piston before the piston gets to top dead center, resulting in pushing against the piston as it comes up versus pushing it down on the downstroke.
So that tells you that preignition happens before the spark plug ignites the fuel and it happens a little too early so that a ping is made but the piston still travels over TDC in time so that the main force of the charge isn't against the piston movement.
The knock sensor is tuned to pinging and will operate as stated earlier in response to it. It will generally stop the pinging before it leads to knock.
Therefore you can run low octane fuel safely in cold weather or low load/highway cruise conditions. Mountain or hilly driving counts as HIGH load.
In summer time even low load conditions will result in pinging in a tuned performance motor and of course some motors will ping with low octane fuel at ANY time.
It is my experience with the duratec and 10:1 compression that 87 octane will suffice if ambient temps are 70F or less. 89 will work most of the time but IMHO it is a waste of money for what you get. 91 or better will always work and is a must for any temps above the 80F range.
If you drive agressively then 91 or better will always be the way to go unless the temps are really cool outside like in deep winter.
Former owner of '99 CSVT - Silver #222/2760
356/334 wHP/TQ at 10psi on pump gas!
See My Mods
'05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red
'06 Mazda5 Touring, 5spd,MTX, Black
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Originally posted by akrump47:
You should dyno your car sometime, with your preferred 87 octane, and see what kind of numbers it puts out and how much pinging there is under load. It would be interesting for comparison sake especially sice you claim to maintain it very well.
Pshhhhh! Dyno'ing the car costs ~$100.00. He'd have to save that $2.40 per fillup for close to a year to be able to afford it. 
Mark
2000 Black CSVT
3.0L Hybrid - 206fwhp & 195fwtq
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Originally posted by Y2KSVT:
Originally posted by akrump47:
You should dyno your car sometime, with your preferred 87 octane, and see what kind of numbers it puts out and how much pinging there is under load. It would be interesting for comparison sake especially sice you claim to maintain it very well.
Pshhhhh! Dyno'ing the car costs ~$100.00. He'd have to save that $2.40 per fillup for close to a year to be able to afford it.
Mark
pwn3d!
Honestly the though of people putting anything but Premium in an SVT makes me mad. Downright GAY!
Sorry but DON'T buy a performance car and then put cheap gas in it. Also I bet a lot of people who do this have power-mods like an exhaust, intake, etc. - which makes them oxymorons.
2000 SVT Turbo 295hp/269ftlb@12psi
#1 for Bendix Brakes Kits!
Knuckles rebuilt w/new bearings $55
AUSSIE ENDLINKS $70
Gutted pre-cats $80/set
A lack of planning on your part does not constitute an emergency on mine!
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Originally posted by Big Jim:
<snip>
Actually, I'm mildly disappoited that my car was factory tuned so that premium fuel is not that critical. I'm also disappointed that there has been so little equipment wise to enable me to tinker with the settings that I used to be able to do by hand.
</snip>
It must not get that hot in your part of CA because mid summer temperatures in Phoenix make it evident that 91 octane is NOT enough. Knock or ping... I don't know, but the car definetely looses power after making a predet type sound. 100 octane resolves this issue, but is expensive... auto parts octane booster sometimes helps, unless I'm doing lots of city street driving.
So how about this... if you live where it can reach 120 degrees, drive with the a/c on, rarely let the secondaries close, and don't have enough faith in the knock sensor to risk your engine, then you CANNOT run less than 91 octane.
morbid
2000 Contour SVT (black)
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Temperature is a big factor in octane requirement. It is not nearly as hot where I live as Pheonix. If I lived in such a hot weather area I may see the need to increase octane.
However, even in hot weather for here (100 Degrees) I can climb either the grapevine grade on Interstate 5 (either direction, but northbound is steeper) or the Conejo grade on highway 101 with the A/C on holding 80 mph (probably more if I wanted to risk the ticket) with no hint of ping or power loss.
Actually I've climbed the Conejo grade much faster than that many times, but I don't remember if any of those times if it was over 100 degrees. It will climb the Conejo at 80 in 5th gear with the cruise control set with the feeling that it could do much more.
I guess that I can't quite get it across to you that I do understand octane. The last car that I owned that could be fully tweeked manually was a 1972 Ranchero. It came with a 429. When I threw a rod, I replaced the bottom end with a Lincoln 460 and added a Cobra Jet cam as well as a Super Cobra Jet intake manifold and liberally ported the heads to match. Carburation was from a Motrocraft 4300D that came off from a Pantera (850 cfm). I could play with the mechanical advance curve, the vacuum advance curve, the carb jetting, the trans shift points, and even the carb secondary openings to my hearts content. Others that drove it at the time referred to it as a bomb because of the explosive acceleration. I could come to a full stop at the foot of the Conejo grade and go over the top at over 120 with a full load of bricks in the bed. It was tuned so tightly to premium fuel that I would get a trace ping just from going from my house at about 1000 feet to a trip to the beach at near 0 feet.
My SVT just isn't near as sensitive, and I'm disappointed.
Jim Johnson
98 SVT
03 Escape Limited
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Originally posted by morbid:
Originally posted by Big Jim:
<snip>
Actually, I'm mildly disappoited that my car was factory tuned so that premium fuel is not that critical. I'm also disappointed that there has been so little equipment wise to enable me to tinker with the settings that I used to be able to do by hand.
</snip>
It must not get that hot in your part of CA because mid summer temperatures in Phoenix make it evident that 91 octane is NOT enough. Knock or ping... I don't know, but the car definetely looses power after making a predet type sound. 100 octane resolves this issue, but is expensive... auto parts octane booster sometimes helps, unless I'm doing lots of city street driving.
So how about this... if you live where it can reach 120 degrees, drive with the a/c on, rarely let the secondaries close, and don't have enough faith in the knock sensor to risk your engine, then you CANNOT run less than 91 octane.
Amen to that! I grew up most and spent most of my life in Tucson. It is hot there and hotter in Phoenix. I could never run less than 91 in AZ except maybe in the coldest part of winter (50F range  )
Former owner of '99 CSVT - Silver #222/2760
356/334 wHP/TQ at 10psi on pump gas!
See My Mods
'05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red
'06 Mazda5 Touring, 5spd,MTX, Black
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Originally posted by Stazi:
pwn3d!
Honestly the though of people putting anything but Premium in an SVT makes me mad. Downright GAY!
Sorry but DON'T buy a performance car and then put cheap gas in it. Also I bet a lot of people who do this have power-mods like an exhaust, intake, etc. - which makes them oxymorons.
The Vulcan Taurus has pinged for over a year now and no ill effects. It has 111K miles and it still runs wonderful. I understand your point about pre-ignition, but I don't think this is as much as a problem as you make it out to be. You might laugh at someone saving some money but not everyone cares about being a boy racer all the time and a penny saved is a penny earned.
People can do what they want and sometimes they know more than you do. The engine is not going to blow up from using 87 octane unless the driver is a fool and never kept his engine clean from carbon buildup and the like.
2000 Contour SE
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Originally posted by Majisto:
Originally posted by Stazi:
pwn3d!
Honestly the though of people putting anything but Premium in an SVT makes me mad. Downright GAY!
Sorry but DON'T buy a performance car and then put cheap gas in it. Also I bet a lot of people who do this have power-mods like an exhaust, intake, etc. - which makes them oxymorons.
The Vulcan Taurus has pinged for over a year now and no ill effects. It has 111K miles and it still runs wonderful. I understand your point about pre-ignition, but I don't think this is as much as a problem as you make it out to be. You might laugh at someone saving some money but not everyone cares about being a boy racer all the time and a penny saved is a penny earned.
People can do what they want and sometimes they know more than you do. The engine is not going to blow up from using 87 octane unless the driver is a fool and never kept his engine clean from carbon buildup and the like.
Now that's just plain dumb to me.
Continuous pinging is still harmfull. Small amounts of it are negligible but for a YEAR? I think Stazi pointed out that your pistons will have pits in them and this is kind of what he was talking about. Your pistons probably look like a small scale lunar surface if you ping all the time for a year (all the time means everytime you accelerate, not cruise).
I stated that the few initial pings befoe the knock sensor pulls some timing wouldn't hurt anything, but that was a very narrow statement with the purpose of pointing out that a knock sensor will save the engine from the damaging knock because it detects the light pings that precede it.
BTW, that's a TAURUS you're referring too, not a high performance car by a long shot. THe SVT is much closer to the realm of performance though some debate that it really is a performance car.
Former owner of '99 CSVT - Silver #222/2760
356/334 wHP/TQ at 10psi on pump gas!
See My Mods
'05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red
'06 Mazda5 Touring, 5spd,MTX, Black
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