Ok im looking around ebay at 350 crate motors
http://cgi.ebay.com/ebaymotors/CRATE-ENGINE-MOTOR_W0QQcmdZViewItemQQcategoryZ46093QQitemZ46429 28257QQrdZ1QQsspagenameZWDVW
At that site it is a 350 small block and i want to learn more so i thougt you guys would be able to help most
1.The compretion ratio is 9.1:1 what are they comparing
2.the rocker arm ratio is 1.5:0 ehat are they comparing
3.what is a rocker arm
4.How many miles to a gallon do you think this motor would get
5.How much is the 92 octane gas
Thank you!

The compression ratio is the ratio at which the pistons compress inside the motor during movement.

Rocker arm is a part that pushes valves down.

As for MPG.. i cant help you there, can be anything but dont expect great mileage.

92 octane gas runs for around 3.10 here in Pittsburgh.

Hope i helped you some.

You did thanks does onyone still know how many miles it would get

1.The compretion ratio is 9.1:1 what are they comparing

The compression ratio is an indication of how much the volume decreases for the swept area. In other words the engine is in the middle of the useable compression that can be supported by gasoline sold today. Really old cars like late 40's had 6.0:1 compression ratios; Olds started a horse power war raising the compression of their Rocket Power™ engines to 8.5:1 in the mid fifties; which peaked in the early seventies with factory hot rods having 12.5:1 compression ratios that required very high octane gasoline (only available today as racing fuel).

Even at 9.1:1 compression you could be burning 89 octane grade gas to support it (unless it has a long duration cam to bleed off some of the compression as it runs (called the dynamic compression ratio) it depends upon the tune of the engine.

2.the rocker arm ratio is 1.5:0 ehat are they comparing

They are stating that it has the same rocker arm ratio as a stock Chevy small block for a first gen 350. Aftermarket and later Chevy engines offer 1.6:1 rocker ration to get more lift out of the cam.

3.what is a rocker arm

The rocker arm sits beneath the valve cover above the valve and spring held in place by a stud. It converts the upward lift of the cam into the downward force to open the valve. In a stock Chevy they are made of stamped steel mounted on a stud and rely upon a hemispherical ball to act as a fulcrum. The ratio above gives an indication to the efficiency of this third class lever arm. Aftermarket parts are made of aluminum (thought not necessarily lighter than the stock piece they are definitely stronger) and use roller bearings to act as a fulcrum, with another roller at the tip of the arm to reduce friction.

4.How many miles to a gallon do you think this motor would get

Have no way of determining that. Best guess, as sold, would be zero miles to the gallon, because it isn't going anywhere until mounted in a car or truck. Then mileage is a factor of vehicle weight, rolling resistance (that's why they say keep your tires inflated), dynamic factors such as air resistance and parasitic loses in the drive-train, carburetor size, cam choice, final gear ratio, and driving habits.

5.How much is the 92 octane gas

Where I live today BP/Amaco White 93 octane (the closest station to my house) is selling for $2.929 a gallon.

Thank you!

Your welcome.


Larger Dave

You did thanks does onyone still know how many miles it would get sorry repost!

02 camaro you are asking a question that no one can answer for you, Larger Dave gave you a great explantion for why it can not be answered. Just keep reading here and buy you some books to read and you will learn a lot fast,Myself i sarted working on farm trucks at 9 and reading all the hot rod mags i could and anytime i could get a chance to turn a wrench on something i did. just hang in there,,Frank

You did thanks does onyone still know how many miles it would get sorry repost!

MPG will very according to,
1) Type of vehicle the 350 goes into?
2) Rear gears
3) Street/highway use.
4) Are you a lead foot.

I have a 350 9to1 in my 1973 Jeep CJ5. SM420 tranny. I'm lucky if I get 8/gal around town.