I have an Accord w/JDM H22A 10.6:1 with a built head everything except cams (i'm saving up for it)

My question is is 87 octane gas ok?? I have a 75 Shot of direct port nitrous, my bottle is empty and I don't see myself filling it anytime soon. I drive hard, hitting vtec. Gas is expensive but I don't want to throw $$$ away.

 

Higher compression = higher octane

 

I don't know about prices of gas every where else, but in TX it is about $1.45 a gallon for regular and $1.55 for super. I fill up at about 10.6 gallons, that's $15.37 for regular or $16.43 for super. At 10.6:1 you need the highest octane. For about one or two dollars more at each fill up you can save spending thousands on another headgasket or replacing pistons with holes in them. $2 is cheap insurence if you ask me.

 

It'll run, just not very good on 87.

 

I still don't understand how people can spend thousands of dollars on a swap, but cheap out on the fuel.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX PAT &raquo;</TD></TR><TR><TD CLASS="quote">I still don't understand how people can spend thousands of dollars on a swap, but cheap out on the fuel.</TD></TR></TABLE>

me either......it says to put premium in, so DO it......

 

So in other words, 87 if fine for my 91 LS Teg with no performance mods? Even if I drive it hard into 6000 RPM durring auto-x.

 

I run 92 daily, but will be going to 110 soon. If you're that concerned about saving$ for taco bell, fill 1/4 tank with 87 and the rest with 91. won't really save you much though.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Brolli007 &raquo;</TD></TR><TR><TD CLASS="quote">So in other words, 87 if fine for my 91 LS Teg with no performance mods? Even if I drive it hard into 6000 RPM durring auto-x.</TD></TR></TABLE>

that's right..
If you don't change the pistons in favor for higher compression pistons, put a thinner headgasket on, or mill your head, you don't need to change to higher octane fuel. 90+ LS engines are rated at around 10.0cr & under if I'm not mistaken, which is fine to run on low octane fuel. But, running higher octane is better in general, it burns hotter creating better performance and I believe petrol companies use better cleaning agents in 91+ octane vs. the other grades of fuel.

 

That was very informative. Thanks.

 

Jason,

You missed the boat on this one (jfwy).

Higher octane burns slower than low octane. This is the reason it is good for high compression motors. The slower burn leads to better knock resistance. If your motor is not optomized for the higher octane, you will actually lose power. If you make no changes to your motor, and it is not a high compression (11:1 plus) motor, and runs fine on the lower octane, you will lose power as the high octane fuel will actually burn slower. That means a smaller bang, which means less power.

However, the gains from higher compression, and advanced ignition timing will easily surpass the losses from the slower burning high octane fuel.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jaker &raquo;</TD></TR><TR><TD CLASS="quote">Jason,

You missed the boat on this one (jfwy).

Higher octane burns slower than low octane. This is the reason it is good for high compression motors. The slower burn leads to better knock resistance. If your motor is not optomized for the higher octane, you will actually lose power. If you make no changes to your motor, and it is not a high compression (11:1 plus) motor, and runs fine on the lower octane, you will lose power as the high octane fuel will actually burn slower. That means a smaller bang, which means less power.

However, the gains from higher compression, and advanced ignition timing will easily surpass the losses from the slower burning high octane fuel.</TD></TR></TABLE>

doh!
thanks for the fix on that .. I had a feeling of tech dislexia when I was done typing my reply.
Check email..jumper question.