Which compression ratio does my 389 have?

Question:
I have a 66 389 with a engine code (YC). I have found that this puts out 290 HP. I am asking this cause I have the orginal owners guide that states (fuel requirements)
2 Bdl, 389 Cu. In. 8.6:1 Regular
2 Bdl, 389 Cu. In. 10.5:1 Premium
So I know theres two different ratios and I cant find any info on which one i have. Can anybody help me??

Answers:

what is this tire size?

yours should be the 10.5.1 with that code,that was the code for the higher horse power engine,,my sister had one in a 66 grand prix,,it had the same engine in it,,good luck hope this help,s.,,have a good x-mas.

---

How To Test A Coil?

with the older engine you would be wise to use premium in it anyway and add some lead replacer as well unless you are going to change the valve seats

---

More Questions & Answers ...

Are the taillights on a 2003 and 2001 Lincoln LS interchangeable?

what can i do to remove dirt from the heat sheild?

I have a leak in my plugged tire and have to fill it up every day. Short on money now. Soultions?

i'm having problems with my 1993 oldsmobile?

Does my boyfriend love his car too much?

Help with transmission problem with my car!?

How do I unfreeze my ignition?

Hyundai, i lifted up my oil filter cap and found it had a white substance on it?

Is there any website telling about the parts of car and how it is designed?

What does the Serpentine belt do?

This article contents is post by this website user, CarQnA.com doesn't promise its accuracy.