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-   -   is 87octane ok w/ N20 for an N/A? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/87octane-ok-w-n20-n-278515/)

theflatlander 03-03-04 03:07 PM

is 87octane ok w/ N20 for an N/A?
 
i have search on this and read the whole nitrous write-up by scathcart. but i haven't seen any info on octane levels and nitrous. so is 87octane ok or am i going to have to bump to 91? also i know timing is good stock up to a 75 shot but is that with other mods i'm putting a RB off-road header to straight pipe and i've got a ported Intake that will be going on.

scathcart 03-03-04 03:14 PM

NO. Octane requirements depend on jetting size.

Also, there is a habit of N/A owners to bump their timing advance. Don't do this. Minimalistic gains during normal use, and not worth any risk with forced induction.

theflatlander 03-03-04 03:16 PM

man that was quick, thanks.

scathcart 03-03-04 03:24 PM


Originally posted by theflatlander
man that was quick, thanks.
What can I say? I rock.
Generally, increase by 40 points octane for every 50 hp increase in jetting.
Here's my rule of thumb:
<40hp: 87 Octane, stock timing.
40-50hp: 89 Octane, stock timing.
50-75hp: 91 Octane, stock timing
75-100hp: 94 octane, 2 degrees WOT retard.
150 hp: 98 octane (4:1 94 pump gas/tolulene), 4 degrees WOT retard
200 hp: 104 octane (1:1 94 pump gas/tolulene), 6 degrees WOT retard.
250 hp: 110 octane (Avgas), 9 degrees WOT retard.

120:1 Premix used in all situations.

This is for 86-91 N/A's, assuming supportive mods existed for each power level.

DEZERTE 03-03-04 04:04 PM

scathcart nose his nauce

Lodivigo 03-03-04 04:46 PM

Posting so I can find this later, great info.

pontious 03-03-04 05:23 PM


Originally posted by Lodivigo
Posting so I can find this later, great info.
Click the little link at the bottom that says SUBSCRIBE. Then you can go to your control panel and it will be there..


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