Octane and compression discussion
#11
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I have heard that you can use toulene(sp) but never used it.
I always put some 110 in at the start of the season just in case. Running 10.7:1 i don't want to take any chances.
http://www.motorsportsracingfuels.co...alculator.html
I always put some 110 in at the start of the season just in case. Running 10.7:1 i don't want to take any chances.
http://www.motorsportsracingfuels.co...alculator.html
#12
I hate the winter!!
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I have heard that you can use toulene(sp) but never used it.
I always put some 110 in at the start of the season just in case. Running 10.7:1 i don't want to take any chances.
http://www.motorsportsracingfuels.co...alculator.html
I always put some 110 in at the start of the season just in case. Running 10.7:1 i don't want to take any chances.
http://www.motorsportsracingfuels.co...alculator.html
My friend who is in the same situation as me, came across a stroke of luck today. He found that a local fuel dock, will be getting a shipment of 91 delivered tomorrow. If it sells enough, he will keep getting more. If that is the case, all our problems are solved. Maybe I should hire a sign plane to fly by the ocean beaches advertising for this guy. May as well start here... Anyone looking for 91 in the area of Jones Beach, head over to Scotty's in Point Lookout..
#13
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I run 8.9 to 1 comp & 36 deg timing with iron heads. I use 89 octain and have not had any issues. Keep your fuel fresh and only buy what you will use in a couple of weeks. I learned my lesson with old E10 fuel, I took out the tops of my rod berrings.
#14
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interesting thread, I just bought 500 gal. of 90 octane premium fuel with no ethanol. my engines call for 93, my fuel dist. told me because this fuel has no ethanol is should be fine. I have some avgas was thinking of mixing some in, what do you fuel guys think? should I add some avgas or is the high test 90 good?
#15
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interesting thread, I just bought 500 gal. of 90 octane premium fuel with no ethanol. my engines call for 93, my fuel dist. told me because this fuel has no ethanol is should be fine. I have some avgas was thinking of mixing some in, what do you fuel guys think? should I add some avgas or is the high test 90 good?
#16
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as most of you know I operate a fuel distributorship and we make and blend our own race gas. I will be more than happy to attempt answering your questions. If it were me I would mix mixed race gas instead of just av gas. It will take more av gas ratio than race gas. Your beat option is to buy some higher grade race gas and mix it. That way you could raise the octane level with smaller quantities of fuel
#18
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I think you answered your own question with the knock sensor set up. Everything else is just a guess....or expensive.
It should only be necessary to install a knock sensor on one engine. As a base like, test with 89 as is. If you detect any knock, start dialing the timing back. We see minimal HP change in the timing on 9.3 CR and iron heads....maybe 10 HP between 34-38 degrees. If you still have detonation and you aren't willing to give up the HP, you can blend in 110 race fuel in five gal increments until you like the answer.
Share the results and everyone on OSO that reads will all buy you a beer
It should only be necessary to install a knock sensor on one engine. As a base like, test with 89 as is. If you detect any knock, start dialing the timing back. We see minimal HP change in the timing on 9.3 CR and iron heads....maybe 10 HP between 34-38 degrees. If you still have detonation and you aren't willing to give up the HP, you can blend in 110 race fuel in five gal increments until you like the answer.
Share the results and everyone on OSO that reads will all buy you a beer
#19
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I run 93 and only add the 110 to the fuel that sat in the tank all winter. I put about 5 gallons to the 60 gallon tank. After that I just run 93 and have had no problems. I did snap a crank last summer and have not pulled the motor yet
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I hate the winter!!
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I found this interesting write up on octane. You guys thinking of avgas, beware, page 2 says it may contain lead. Not that many of us, if any, run cat converters. Its just good info to know.
http://auto.howstuffworks.com/fuel-e...question90.htm
zzsupeboat,
Didnt know the anchorage has good fuel. Thanks for the info.
http://auto.howstuffworks.com/fuel-e...question90.htm
zzsupeboat,
Didnt know the anchorage has good fuel. Thanks for the info.
Last edited by Vinny P; 05-17-2010 at 09:53 PM.