Hi guys,

I have a H22 5th gen car and I wonder if there is any way I can benefit from 98RON octane gas that is sold in my country. My compression is stock. Perhaps just buy type S pistons? What do you think? Shall I advance my ignition. If a H22 works with 91-93 octane I guess with 98 I should be aple to squeeze more horsepowers?

Thanks

 

Well if I'm right I believe the octane ratings there are different, so it might not necessarily be the way you are thinking, but if it was 98 octane on our rating hell yea you could benefit from higher compression, and type s pistons would be the cheap and easy way to go in my opinion

 

It is 98RON octane and it costs 15% more than standard 95 octane. I am sure it is the same grading as in US.
I always use 98 octane but at this point i guess I should put some typs S pistons or even advace ingnition perhaps?
BTW can I use Type S piston without having to sleeve the block? It is all stock?

 

I see you point. I made some reseach and figured it out. So 98 octane in Europe is like 98 minus 5 points = 93 US octane rating. Well this means that Type S pistons are a good choice then How wonder if only the pistons will increase something like 5-6hp?


Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Raven_22 &raquo;</TD></TR><TR><TD CLASS="quote">I see you point. I made some reseach and figured it out. So 98 octane in Europe is like 98 minus 5 points = 93 US octane rating. Well this means that Type S pistons are a good choice then How wonder if only the pistons will increase something like 5-6hp?


Thanks</TD></TR></TABLE>

depends on what else you've done to the car.

breathing mods and bolt ons, yield much higher gains when compression is higher. so let's say you've done it all, and are now getting type s slugs, it might be a 15-20 whp increase. on a stock engine it might be 5-6.

it also depends on the tune, and who's tuning the engine.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Raven_22 &raquo;</TD></TR><TR><TD CLASS="quote">...98 octane in Europe is like... ...93 US octane rating...
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98 x 0.95 = 93.1

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sport Compact Car Magazine &raquo;</TD></TR><TR><TD CLASS="quote">
...there is no direct conversion from RON to AKI[Anti-Knock Index(The US standar)]... sometimes denoted as RON+MON/2(The average between these two tests), but as a general rule, if you take the RON rating and multiply by 0.95 you'll come pretty close to the U.S. AKI rating...</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Raven_22 &raquo;</TD></TR><TR><TD CLASS="quote">Hi guys,

I have a H22 5th gen car and I wonder if there is any way I can benefit from 98RON octane gas that is sold in my country. My compression is stock. Perhaps just buy type S pistons? What do you think? Shall I advance my ignition. If a H22 works with 91-93 octane I guess with 98 I should be aple to squeeze more horsepowers?

Thanks </TD></TR></TABLE>

The H22 runs fine on 91-93 RON+MON/2, which is the way North America rates its gas. 98 RON isn't going to be signifigantly better than 93 RON+MON/2.

You can still crank up the CR with tuning, though. 11:1 type-s pistons are cake on pump gas. And yes, they work on stock sleeves.