SI models...premiume or regular unleaded? - Honda Prelude Forum

KB798 · 01-14-2002, 11:57 PM

what's the requirement? i know on vtec models you need premium (sp?)

Machine Head · 01-14-2002, 11:58 PM

with all my mods I have to run premium..it bogs if I don't and my milage sucks

cantdrive55 · 01-15-2002, 12:05 AM

Premium, states so in the owner's manual. 91 octane or higher.

KB798 · 01-15-2002, 12:38 AM

even si's need premium.

brendon2k · 01-16-2002, 09:02 PM

Si's and vtec's say you need premium but the compression ratio isn't really that high. Rember high octane fuel does not have any more power is just resists detonation more. I have ran premium, midgrade and regular. No real difference. If your car pings when your hard on the throttle then you need higher octane. My friend has a car with a 13:1 comp ratio and he runs off 91 octane I think 10.0 or 9.8 could do fine on regular.

Crate · 01-16-2002, 09:16 PM

when i first got it the guy only used premium...
then when i was broke. .tried 89.. used itever since.. runs fine. no choking, no hesitation.

Deepmist · 01-17-2002, 04:34 AM

It says premium unleaded only on my dash.

Dark Si · 01-17-2002, 02:27 PM

the owner's manual says to use premium unleaded, and that is what i always used with my Si engine. You can get way with 89 octane, maybe even 87, but unless u are very pressed for cash i wouldn't recommend it. Using a lower octane rating than recommended can result in a slight loss of power, and so can using a higher than recommended octane rating. For an Si prelude though, I would say your best bet is to use premium like the manual states.

DClude757 · 01-21-2002, 01:10 PM

damn you crate!!! You had to go and mess with my baby. What the hell is the difference in a couple bucks. Im dissapointed

Crate · 01-22-2002, 06:23 AM

In June if my job offer goes as planned. I might sell you back the lude if you want it? Might do a Lexus sc300 w/ 2jz swap.

DClude757 · 01-22-2002, 06:47 AM

yes i def will want it back. Just keep me posted. Thanks man

brendon2k · 01-22-2002, 01:48 PM

Quote:

Originally posted by Dark Si
the owner's manual says to use premium unleaded, and that is what i always used with my Si engine. You can get way with 89 octane, maybe even 87, but unless u are very pressed for cash i wouldn't recommend it. Using a lower octane rating than recommended can result in a slight loss of power, and so can using a higher than recommended octane rating. For an Si prelude though, I would say your best bet is to use premium like the manual states.

Higher octane fuel does not have anymore power.

Dark Si · 01-22-2002, 08:47 PM

Quote:

Originally posted by brendon2k

Higher octane fuel does not have anymore power.

You're right, it doesn't add more power. However, using too low of an octane can result in a loss of power. Car and Driver did a comparison of octanes in cars. Using too high of an octane in a car that didn't need in resulted in lost power, and using too low of an octane in cars rated for premium also resulted in power losses. They're not significant.. few hp or so, really no big deal