jackass_25 Posted September 4, 2008 Report Share Posted September 4, 2008 hey there, i was just looking around and reading all these posts about heads, dome sizes, elevation, and compression. I was just wondering if someone who knows can make a graph chart or something to compare what PSI the cylinder is running at to what octane of gas should be used. maybe even make it a sticky post so everyone can just look at that after they do their compression test to find out what fuel to use. Thanks Aaron Quote Link to comment Share on other sites More sharing options...
mawcusb Posted September 5, 2008 Report Share Posted September 5, 2008 Do a search, idiot. Man you must be a newbie or something hahahahahahaha Quote Link to comment Share on other sites More sharing options...
TeamRealtreeHD Posted September 5, 2008 Report Share Posted September 5, 2008 Do a search, idiot. Man you must be a newbie or something hahahahahahaha You're telling him he is an idiot and a newbie? Look at you and the date you signed on. You need a punch in the mouth or something you fucking loser. This site is known and is proud of the guys on here willing to give the information needed to another member. Then we have guys like you. Quote Link to comment Share on other sites More sharing options...
BlntdEyez Posted September 5, 2008 Report Share Posted September 5, 2008 You're telling him he is an idiot and a newbie? Look at you and the date you signed on. You need a punch in the mouth or something you fucking loser. This site is known and is proud of the guys on here willing to give the information needed to another member. Then we have guys like you. Well said Realtree!!! Quote Link to comment Share on other sites More sharing options...
spurdy Posted September 5, 2008 Report Share Posted September 5, 2008 I think my "sig" says it all!! Quote Link to comment Share on other sites More sharing options...
MikeNick Posted September 5, 2008 Report Share Posted September 5, 2008 I think my "sig" says it all!! lol Quote Link to comment Share on other sites More sharing options...
TeamRealtreeHD Posted September 5, 2008 Report Share Posted September 5, 2008 hey there, i was just looking around and reading all these posts about heads, dome sizes, elevation, and compression. I was just wondering if someone who knows can make a graph chart or something to compare what PSI the cylinder is running at to what octane of gas should be used. maybe even make it a sticky post so everyone can just look at that after they do their compression test to find out what fuel to use. Thanks Aaron Aaron, there isn't a chart right now... but I can guarantee you one thing. If you do a compression test and come back here with the reading, you will have the answer to the octane needed to suit your motor. I too think there should be a chart. But as of right now, it is a toss up in the air as everyone will be different. Usually anything above 150 PSI it is a general rule of thumb to mix 50/50 with premium pump and race fuel. I am running 190 PSI and run 105 Octane (93 premium pump mixed with 116 Race 50/50) Report back when you get a reading, we can guide you. Quote Link to comment Share on other sites More sharing options...
fastrthnu Posted September 5, 2008 Report Share Posted September 5, 2008 You're telling him he is an idiot and a newbie? Look at you and the date you signed on. You need a punch in the mouth or something you fucking loser. This site is known and is proud of the guys on here willing to give the information needed to another member. Then we have guys like you. I think that was sarcasm, its possible he just dealt with the same thing? Anyways, yes there is. Google search a psi to compression ration chart, then search your compression ratio to octain. with oil Id say 9.5-10:1 is the best for 93. IMO. There have been previous posts on here and I know I have posted this info before too. Or abouts 155-160psi on 93. This is a safe baseline. timing advance and other variables apply too. The chart you find will most likely be for straight gas w/o oil, but with oil, I like to be safer with a less efficient hotter burn. If you run a cool head with engine ice and have a good tad rich jetting, its safer to run lower octain than say someone who is running a hot motor reving all the time with a stock head, std antifreeze and timing advanced 7 degrees yadda yadda. Just my .02 Quote Link to comment Share on other sites More sharing options...
spurdy Posted September 5, 2008 Report Share Posted September 5, 2008 Aaron, there isn't a chart right now... but I can guarantee you one thing. If you do a compression test and come back here with the reading, you will have the answer to the octane needed to suit your motor. I too think there should be a chart. But as of right now, it is a toss up in the air as everyone will be different. Usually anything above 150 PSI it is a general rule of thumb to mix 50/50 with premium pump and race fuel. I am running 190 PSI and run 105 Octane (93 premium pump mixed with 116 Race 50/50) Report back when you get a reading, we can guide you. Just curious.....why would everyone be different? Compression determines what fuel. Several factors determine compression, but once compression is known, fuel octane can be determined. Do you worry at all with your 50/50 mix at 190 compression? I am at 195 compression running VP Red at 110 octane and was thinking of going to VP C12 because of the high compression. I really wanted to be at the 180 - 185 range for the 110, but we had to go up to a 21cc dome cut for a 4 mil just to get it down that far from 210! Quote Link to comment Share on other sites More sharing options...
TeamRealtreeHD Posted September 5, 2008 Report Share Posted September 5, 2008 Ok, let me say this quick... I said "general rule of thumb" "Everyone's application will be different" Quote Link to comment Share on other sites More sharing options...
boneyardbanshee. Posted September 5, 2008 Report Share Posted September 5, 2008 Do a search, idiot. Man you must be a newbie or something hahahahahahaha What an ignorant prick. the guy has been a member for nearly a year before you a has two posts. What do you think he has been doing? HHMMM probably using the search feature. Hell I was all over this site for almost two years before I even signed up, just learning, so I didnt have some bag of ass like you shoot your mouth off. On top of that he said he had read alot of posts and he made a valid point. This would not be a FOURUM if people were supposed to come on here and just read. FUCKING NEWB Quote Link to comment Share on other sites More sharing options...
TeamRealtreeHD Posted September 5, 2008 Report Share Posted September 5, 2008 Do you worry at all with your 50/50 mix at 190 compression? I am at 195 compression running VP Red at 110 octane and was thinking of going to VP C12 because of the high compression. I really wanted to be at the 180 - 185 range for the 110, but we had to go up to a 21cc dome cut for a 4 mil just to get it down that far from 210! Your engine builder will guide the way... My motor, with all my mods, and timing, etc. is calling for 104-105 octane. If you were worried about your octane levels, and if there was a case to worry about, you would have known by now. Whoever built the motor will tell you what to run. To the T I could have easilt been running 110, running it straight, and I would have if I needed to. But I don't. And in that case, I am more than happy to mix. Wasted money otherwise if not needed Quote Link to comment Share on other sites More sharing options...
spurdy Posted September 5, 2008 Report Share Posted September 5, 2008 Ok, let me say this quick... I said "general rule of thumb" "Everyone's application will be different" The last post after yours explained the difference why it isn't necessarily just "compression = octane". I wasn't considering the effect of the oil mixture and timing. Perfectly logical though. It wasn't posted at the time I started my reply. SP Quote Link to comment Share on other sites More sharing options...
TeamRealtreeHD Posted September 5, 2008 Report Share Posted September 5, 2008 The last post after yours explained the difference why it isn't necessarily just "compression = octane". I wasn't considering the effect of the oil mixture and timing. Perfectly logical though. It wasn't posted at the time I started my reply. SP I know what you meant... :thumbsup: Quote Link to comment Share on other sites More sharing options...
OKCterror Posted September 5, 2008 Report Share Posted September 5, 2008 total ownage.lol. Quote Link to comment Share on other sites More sharing options...
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