Max boost on 91 and 93 Octane gas? - Honda Prelude Forum

BlueShadow · 03-24-2002, 01:38 AM

Hey everybody,

I was wondering whats the max I can boost on the following

91 and 93 Octane gas

9.0:1 compression

And also is it better to use a "stock" thickness head gasket or a thinner one? say if I was to go with 9.0:1 Pistons and a thinner head gasket, what kind of benifits and problems am I looking at?

TIA

BlueShadow · 03-26-2002, 07:21 PM

whoa...everyone is looking at me like I said something stupid...

schwett · 03-26-2002, 09:14 PM

i think people probably need more info... mostly what kind of fuel and timing management are you looking at. more retarded timing=more boost on a lower octane...

00G · 03-26-2002, 10:53 PM

There are 600+whp supras running on pump gas. How much can you afford to handle? Even at a built 10:1 turbo'd motor, it is all about tuning. How much do you want?

BlueShadow · 03-27-2002, 01:40 PM

Quote:

Originally posted by 00G
There are 600+whp supras running on pump gas. How much can you afford to handle? Even at a built 10:1 turbo'd motor, it is all about tuning. How much do you want?

I want to be able to run 15 PSI maybe 18 PSI on 9.0:1 (built) on 91 Octane at the minimum. last I checked CA had 92 at my local pumps, maybe going to 91 soon.

I guess if I retard it enough I should be able to run 91 octane and 9.0:1, but I'd probably ave to swap out exhaust valves too.

schwett · 03-27-2002, 02:55 PM

premium unleaded in CA went to 91 about a year ago.

Quote:

Originally posted by BlueShadow

I want to be able to run 15 PSI maybe 18 PSI on 9.0:1 (built) on 91 Octane at the minimum. last I checked CA had 92 at my local pumps, maybe going to 91 soon.

I guess if I retard it enough I should be able to run 91 octane and 9.0:1, but I'd probably ave to swap out exhaust valves too.

NirVTEC · 03-28-2002, 10:09 AM

Really??? In CHI I have a station down the block pumping 104...It's almost $4 per gallon though!!!

93 is the norm here...Oh, you're in Korea!!!

schwett · 03-28-2002, 10:29 AM

yeah but i assume from his post he was referring to what gas he'd have available once he got back to the u.s.... to california. because of emmissions laws, california gas is formulated differently. because of the extra cost of that, our "premium" gas is only 91 octane. you cannot get anything higher except for race gas, which is available at a few stations at around $3.50-$4.50/gal, 100 octane.

Quote:

Originally posted by NirVTEC
Really??? In CHI I have a station down the block pumping 104...It's almost $4 per gallon though!!!

93 is the norm here...Oh, you're in Korea!!!

BlueShadow · 03-28-2002, 10:46 AM

Quote:

Originally posted by schwett
yeah but i assume from his post he was referring to what gas he'd have available once he got back to the u.s.... to california.

Yep, thats what I was talking about, I left CA (Fairfield, Solano county) about 5 months ago(NOV 01) and the last time I filled up my car It was with 92. I've heard that since then that it has lowered to 91.

I was just wondering what PSI I could run on 91 Octane (minimum) and what timing control I would need, Or how I would go about running 15 PSI on 91 octane.

00G · 03-28-2002, 12:06 PM

Tuning tuning tuning. If you're worried about timing, any boost retard timing will work. But with 14-15psi, you'd probably want some aftermarket ecu to have total control and you won't need any timing retard.

XES · 03-28-2002, 07:31 PM

With Hondata 4B, 9:1, I ran 18psi on the street everyday, with no problems.

92 octane gas.