Quick Answer: What Is The Compression Ratio On A Stock 454?

What octane is needed for 11 1 compression?

95 Octane.

Gasoline with this octane number is known in Indonesia under the brands Pertamax Plus (produced by Pertamina), Super Extra (produced by Shell), and Primax (produced by Petronas).

This type of gasoline is advisable for car engines with compression ratios of 11:1 to 12:1..

What keeps a camshaft in place?

The lifters push the cam to the rear and the thrust on the timing gear holds it from going any further back so the two of them hold the cam in place.

How does a camshaft increase horsepower?

Performance cams increase the duration and timing of the valve openings during the engine stroke, increasing horsepower and making your car accelerate more quickly. You’ll idle slightly rougher with a performance cam, but get a throaty rumble that’s desirable for some gearheads, depending on your vehicle.

How much compression should a 454 have?

The stock compression for a 454 with 781 heads and flattops is around 7.75:1 cr. Then the bigger cam with the later intake valve closing point will reduce cylinder pressure even more. I would except to see 110 to 125 psi numbers.

What’s the biggest cam for a stock 454?

Edelbrock 7162 Performer Cam and Lift Kit – the best cam for stock 454. Duration at 050” Lift: 240 int./246 exh.

What is a good compression ratio?

Compression ratios usually range from 8:1 to 10:1. A higher compression ratio — say, from 12:1 to 14:1 — means higher combustion efficiency. Higher compression ratios and combustion efficiency mean more power with less fuel, and fewer exhaust gases.

What compression ratio is too high for pump gas?

High compression pump gas engines, I wouldn’t be afraid to run 11.5-12:1 on pump gas with an EFI Alum.

Is 90 psi a good compression?

Generally, readings below 90 PSI for modern two-stroke outboards indicate a problem; most will produce cranking compression readings in the 90 to 105 PSI range, depending on the engine year, make, and model. … If your compression readings are low, or some cylinders low but others high, there are a few potential causes.

How much horsepower does a 454 have stock?

250hpSo the average stock 454 is 250hp. They changed the rating system from gross horsepower to net horsepower in 1972 net is more realistic but not always dead on.

What is the highest compression ratio for 91 octane?

9.3 : 1To release all the potential power of 91 octane gasoline, it is necessary for an engine to have a compression ratio higher than 9.3 : 1. _______3. Any gasoline engine will efficiently burn any octane fuel.

Is 120 psi enough compression?

You should start to worry if one of your cylinders is getting close to 100 psi. Most new engines in good condition compress at around 175 psi. … Suppose that #4 cylinder were at 120 psi, the difference ratio would be 31.4% which would indicate excessive wear in the cylinder.

How much compression should a 4 stroke have?

A compression test reveals the condition of your engine’s valves, its valve seats, and piston rings and whether these parts are wearing evenly. Healthy engines should have compression over 100 psi per cylinder, with no more than 10 percent variation between the highest and lowest readings.

What size is a 454 bored 30 over?

SO assuming a 454 bored . 030″ it should be around 462 cubic inches.

What year did Chevy stop making the 454?

1975The Chevrolet 454 was eliminated from most passenger cars by 1975 but remained a viable powerplant in heavy-duty Chevrolet trucks through 1996.

Does higher compression make more horsepower?

All other factors being equal, an engine with a higher compression ratio will deliver a higher thermal efficiency. This means that the engine is able is turn more of the heat generated from the combustion process into horsepower instead of wasted heat.

Can you run nitrous with high compression?

Nitrous complements high compression engines well mainly because of its extremely cool intake charge temperatures. This cooling effect wards off detonation when run on pump gas in high comp engines.

How can I get more power out of my 454?

How Do I Get More Power out of a Chevy 454?Improve the fuel and air intake system. The more fuel and air you are able to get into your Chevy big block engine, the more power it will be able to produce. … Replace the stock exhaust system with a high-flow system. … Replace the stock timing parts with ones tuned for racing. … Bolt on a supercharger.

How much compression should a 350 Chevy have?

You should have probably somewhere in the 150-170 psi range.

What is the highest compression ratio for 93 octane?

9.5:1We are being told by most piston manufacturers that 9.5:1 is the most you should run in an engine with cast iron heads on 93 octane pump gas. Because aluminum conducts (dissipates to the cooling system) heat much faster than cast iron does, you can run 10.5:1 with aluminum heads on 93 octane.

What octane do you use for 10 1 compression?

10.5 to 1 comp, with 93 octane, timed right will be fine.

Which is better a 454 or a 350?

In a light to medium weight car, a 350 will probably offer you the happiest experience, especially in a daily driver role. In a truck, the 454 will probably feel better to your foot. In an all out performance car, the 454 will probably be more likable as long as the car is a straight line car (drag racing etc).