How can you determine how much you can increase the HP/boost with an increase in octane? Let me give an example: Say, you increase your R+M/2 octane from 93 to 98 by some additives (such as xylene, etc). How can you determine how much more boost you can run (or I should say, how much more HP you can make) with such an octane increase?

I imagine that it all depends on your specific setup (your turbo, first and foremost). Is there a general rule of thumb that can be followed? How about a complex set of equations that I can pound away at?

 

Bump for the question...

 

octane boosters suck. take a look at your plugs when you're done

 

there is no exact calculation for this. this is why there are tuners

 

Well, there has to be some sort of method of determining this. I mean, If I put in 104 at the track instead of 91 from the pump, can I boost 2 more psi? 10 more psi? Make 20 more horsepower? 100 more horsepower? Any personal experiences could work too.

 

bumpski

 

its not really plug and play, you'll have to get it tuned for track and street. 2 chips.
i think this topic was up last week or so, i forgot, but try the search. there is some info on the gntype.org website as well.

 

Well i just would like to point out that fuel, weather it be leaded race gas, or pump gas, may not increase HP by alot unless you have a high HP application. Keep in mind that octane is the rating of a fuels ability to resist detonation and preignition. Octane is rated in RON, MON and R+M/2. Also, with race gas, a major issue i the burning speed. Burning speed is the speed at which the fuel releases its energy. There are many other factors, such as energy value and specific gravity, but ill leave it at that, hehe.... well unless someone can elaborate futher.

 

Boost increases the speed at which the fuel burns. This is why we retard timing per psi to prevent the fuel from burning so fast that it detonates.. higher octane burns slower so it allows you to run more boost or more timing. It allows you to make more power because of its resistance to detonation. If ur car is tuned for 93 don't put in race gas it will hurt more then it helps! and no, sorry I don't know any formula's for how much you can increase boost per octance. Wish i did!

 

Very well said chris. Also, some people neglect to research the gas they put in their car. Some people might go to the track, etc, and see a few types of race gas. Little do they know that even tho some gasses have slightly more octane, it might not be well suited for their application, due to burning characteristcs, and/or specific gravity.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIXTYdashONE &raquo;</TD></TR><TR><TD CLASS="quote">Very well said chris. Also, some people neglect to research the gas they put in their car. Some people might go to the track, etc, and see a few types of race gas. Little do they know that even tho some gasses have slightly more octane, it might not be well suited for their application, due to burning characteristcs, and/or specific gravity. </TD></TR></TABLE>

thats true ron, don't some race gas' have more oxygen in them then others too?

 

Well chris, im not a 100% sure what the calculatons are, but for instance, the fuels energy value is an expression of the potential of the fuel the energy vaue is measured in BTU's per pound, and not per gallon. Its relevant becaise the air fuel ratio is measured in weight, not volume.
Look at C12 and C16 for example; C12 has a specific gravity of .717 A 60* F.. C16 has .730 @60* F... C16 has a much higher lead rating tho, at 6 grams per gallon,, as opposed to C12's 4.2 grams per gallon