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California 91 octane and comp. ratio
I'm considering a Ford crate engine such as the 460/535hp. This one has a 10.5:1 comp. ratio. Will this run on 91 octane? If it knocks, will retarding the timing be enough to be safe or should I look at lower compression engines? I can add a little 100 octane, but it's $4.25/gal at my local 76 station!
Thanks, |
Many people run this engine. Haven't heard of any detonation problems.
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I currently run Turbo Blue in my bike and will run a mixture of it with pump gas in the cobra. Would love to run straight Turbo Blue in the car, but at $4.00 a gallon that would be cutting into my DVSFII car raffle ticket money!!!
Jeff - what fuel do you run?? Brian p.s. it don't smell too bad either :D :D |
Thanks all. If the price of pump gas keeps going up, race gas may not seem so bad ;). Any comments regarding the best street engine of the crate motors 514, 460 or 392?
Regards, |
Barry, I opted to spend a couple bucks more and go the custom built route as I did not want the engine to be the weakest link. I'm sure that the crates are good although I was concerned about the internal components. I also received a warranty with my motor......it is not a long warranty but will cover me for this years driving season (just a little piece of mind).
Brian |
Isn't 93 octane available? I thought it would be throughout the state of CA. SInce that is an aluminum-headed motor, 10.5:1 is like 9.5:1 on an iron-headed due to better dissipation. Should be fine.
Bill |
I opted for the Ford factory 514
It has 9.5 to 1 compression, and as stated, you can knock off about 1 point for the aluminum Cobra Jet heads...so it's like 8.5 to 1
Several guys have related their total satisfaction with this motor, and it (like the other SVO motors) cannot be beat for price vs what you get. Will be here soon in my turn key West Coast...looks like April or May at this point....I will be reviewing the car and all accessories in the months after I get it. |
BinB:
I though the 535 HP motor has 10.5:1 and the 514 has 9.8:1 Either way, not much of a problem. Bill |
California is 91 octane max throughout, as far as I know. And they charge the same price as if it's 93! Yes, the 460 is supposed to be 10.5:1 while the 514 is 9.8:1 according to spec. Is it insane to put a 600 hp engine in these cars? I guess too much is just right. How often do you think you need to adjust valve lash on this motor? How long will it last with street use?
Barry |
Barry:
The pumps say 93 octane, am I missing something? Wouldn't surprise me. General rule of thumb on valve lash is 2 -3000 miles. Bill |
Maybe 91 is just an Los Angeles thing. What brands in San Diego have 93? None available here except for "76" 100 octane race gas at 1 or 2 stations ($4.25).
Barry |
Barry:
I used to live in L.A. and the Bay Area, now San Diego. My recollection is 93 octane in all those places. Bill |
All major distributors in San Diego and the rest of California have dropped the octane rating to 91. Just some owners haven't changed the sticker on the pump. They will change the next time the wieghts and measures people come in to test the pumps.
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Thanks xlr8or.
Bill |
91 Octane
I just moved from Michigan to California and am running a supercharged 350 in my Chevy truck. I have only one problem with running 91 octane and that is when I am towing and climbing a grade the engine will ping. I just put a bottle of octane boost in the gas and no more ping. California is all 91 octane and will stay that way for good. My engine does have aluminum heads and runs 8 lbs of boost at 8.5:1 compression ratio. It was dynoed at 500 hp at 5500 rpm so it is no slouchin the performance. But if you have aluminum heads life can go on with 91 octane. You can also ceramic coat the piston tops and that also reduces the need for higher octane.
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Yep, it's 9.8 to 1...
As far as 600 horsepower, yes, it's a lot, my West Coast weighs a bit more than the more original designs, mine has all the running gear to handle the horsepower...the weakest link might be the Richmond Over Drive 6 speed, but I suspect it will last way longer than most think it will...
I have been informed that the valve adjustments need to be done on the mechanical lifters about every 3,000 miles...this is very similar to many motorcycle engines, and does not bother me..they are readily accessable ....the only problem would be if you used the car for long distance touring....we will instead tow it in a warrior trailer, deploy the cobra or motorcycles along the way. 600 horsepower can get you in a lot of trouble fast, and if you have leadfoot, not recommended....but the 535 horse model is scant difference, you can get in just about as much trouble there ! |
How long do these crate motor last? The more and more i look at these engines the more i want to scream...It is such a tough choice. I just dont want to have huge upkeep costs just because of the engine. Venting done.
GS |
What was the official reason for the lowering of the octane. was it emissions?
rphubbard, I don't know if you have read the previous thread on laquer thinner instead of octane boost but you should look it up if you haven't. I've been running in my big block chev. I mix about 1 gal with a full tank of 91 (approx. 20 gal.). It really wakes up runs nice. A lot nicer than boost. |
Tongue Pirate,
The reason for the switch to 91 is for only one reason and that is the supply pipeline only wants to handle as few different levels of gas as possible so everyone agreed to 91 octane. It has nothing to do with emissions. As far as octane booster, I worked for Roush for a couple of years and just left the company due to downsizing, I have stayed with octane booster because of things I have seen at work. But you have to be careful on what brands you do buy. I like the NOS brand and some others. I would also recommend mixing turbo blue with your fuel. But I am just leary of paint thinner but it doesn't seem to hurt. I found one bottle does the trick for me in my 65 gallon tank so a little bit goes a long ways for me. |
Too bad they didn't ditch the 91 and keep 93 and 87.
Bill |
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