89 Octane Minimum

[grasscutter]

Have you ever heard of a car that requires 89 octane as a minimum? Usually the minimum will be 87 octane or 91 octane.

 

[The Critic]

5.7L HEMI engines recommend 89 octane for optimal performance.

 

[eljefino]

Nearly every entry level car in the 1960s.

They had modern OHV designs and decent compression. Regular (leaded) gas was 89 octane. When it was banned in the 80s gas stations offered unleaded 89 and people bought it for their 87-spec cars as a "treat."

Also what Grasscutter wrote-- there were other some semi-modern Dodges that took 89, even an Intrepid IIRC.

 

[SC Maintenance]

Certain years of the R51 pathfinder did. And some years spec 87. Most believe it was due to CAFE and run 87 anyway.

I believe the LR3 Land Rover was like this also?

 

[kschachn]

Have you ever heard of a car that requires 89 octane as a minimum? Usually the minimum will be 87 octane or 91 octane.

Which one do you have that has this recommendation?

 

[hemitom]

Chrysler 300 that I had recommend 89

 

[Skippy722]

All 5.7 HEMI’s with automatic transmissions recommend 89, but can operate on 87.

When equipped with a manual, they lose MDS and REQUIRE 91 octane.

 

[Jetronic]

Have you ever heard of a car that requires 89 octane as a minimum? Usually the minimum will be 87 octane or 91 octane.

95 ron minmum on mine. that still causes some knock in summer, but 98 doesn't. the lowest I can get is 95 ron.

 

[y_p_w]

Saab I think. But for the most part it's 87/91/93, even though most vehicles can tolerate lower by dialing back the timing.

I think motorcycles often called for 89 AKI. Not sure if that's the case now.