I know you are suppose to run 87 in stock and 91 with a pipe but what about y pipe and can. Also why do you have to run 91 with a pipe. If you do not increase compression, or advance timing. These are the things I would think you need to increase your octane rating.Thanks for any input.
87 or 91 octane gas with a y pipe and can
- Thread starter walker
- Start date
Not sure why you say you "have to run 91" with a pipe.........I have an '07 M1000, piped, can, y, high comp head and I run 87 all day every day ......much of the time cobbed WFO and the sled rips and rips consistantly.
Keep in mind.....the elevations I ride are 9-12K. The story may be different for someone who runs in the 2500-6K elevations.
Keep in mind.....the elevations I ride are 9-12K. The story may be different for someone who runs in the 2500-6K elevations.
If it was my sled i would run 91
better safe than sorry, it's a mod sled now, not stock
better safe than sorry, it's a mod sled now, not stock
I run 91 all the time regardless of what manufacturers say or aftermarket parts people say. You don't know what's in gas now a days. At least with 91 you should be close to 87. ( I hope that makes sense). My M8 and M7 run well on 91. You have a $10,000 sled, $5,000 trailer, all pulled by a $40,000 truck, why worry about .10 cents a gallon.
The same argument we hear ALL THE TIME. The answer is, because it's a waste of money & power. You're PISSING performance down the drain by running more octane than needed. Do a search of the hundreds of conversations about it, there is no reason to run that. If you are that worried about octane, toss a 16oz bottle of toluene in your trunk in case you have problems with the octane light. We have warning sensors on these sleds for a reason. (btw, this is assuming you're talking about stock)
btw, we can't get non ethanol fuel anymore in CO... such BS
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The reason slp says up the octane is because the pipe increases the rate of compression.
If you are at 0-3000 ft you want to for sure, if your in the deep at 3-6000ft then yes as well, from there it all depends how good of fuel map you have. I run 91 from 7-11000ft just because, there are few times I have had extreme under hood temps that could cause deto, so its just a saftey, Think of it this way at 10,000 ft you are loosing 1/3 of your hp, even with the slp pipe that drops you down around 130hp, less than stock, but you are running a little more rpm. I would think 87 would be fine as long as you don't get extreme heat under the hood. I'll stick with non-e 91 for now, but wont go over that. Thats with my m1000 anyway, if I had the det sensor I would prob run less.
If you are at 0-3000 ft you want to for sure, if your in the deep at 3-6000ft then yes as well, from there it all depends how good of fuel map you have. I run 91 from 7-11000ft just because, there are few times I have had extreme under hood temps that could cause deto, so its just a saftey, Think of it this way at 10,000 ft you are loosing 1/3 of your hp, even with the slp pipe that drops you down around 130hp, less than stock, but you are running a little more rpm. I would think 87 would be fine as long as you don't get extreme heat under the hood. I'll stick with non-e 91 for now, but wont go over that. Thats with my m1000 anyway, if I had the det sensor I would prob run less.
im going to throw this out there... 09 m1 with full slp, open intake, pc3, 2200ft run 87 octane with 7% eth. i havent ran just straight 87. tried a few bottles of lucas octane booster and going to give a few cans of torco a try and see if egts get somewhat affected. 150 miles like this and havent burnt down. had to take ypipe off and get egt probe mounts welded up and pistons looked good all around. soo i continue.....
Like I said, prob never have a problem until you create some extreme heat in the cylinders, Only time its happened to me is after 15 seconds of WOT with snow plugging all the vents, hot enough under the hood stuff was starting to melt.
FYI At WOT if your egts ever start to go down after they went up, its because the heat is staying in the cylinder, DETO. You will also hear a rattling noise like a exhaust spring bouncing on the pipe, and a loss of power.
FYI At WOT if your egts ever start to go down after they went up, its because the heat is staying in the cylinder, DETO. You will also hear a rattling noise like a exhaust spring bouncing on the pipe, and a loss of power.
by that time its probably tooo late.
B
I had a y-pipe and can on my 09 m8 and ran 87 with no issues
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