[demarques_191]

I have read many hotrod magazines, read through forums and seen so many people post HP and TQ numbers of what 355's can put out identical power or close to it... Well the torque was down some but... The 355 would basically need a little more compression than the 383? opinions... opinions...

[1Gary]

The real question when it comes to C.I. is where in the rpm range the torque curve begins.The 383 is going to be a lower rpm and likely broader if matched parts are selected to the natural attributes of a 383 torque monster.

[vinniekq2]

you can make a certain amount of power based on how much fuel you convert to heat. The process has air and fuel. The 383 has more space to burn air and fuel than the 355

[killerformula]

I agree with the above. If you look at the area under the curve of horsepower in the usable power band (idle-5500 or 6000 RPM for a street motor), you'll see some very real increases with an extra 30 cubes.

K

[ap72]

A 350 and a 383 will have very close peak power levels but the power will come in early with a 383, which means less RPM which is usually what you want on the street. Same thing with a 302 chevy vs a 383 chevy, about the same peak power but the 302 will have to rev higher to make it which means the valve train will take more abuse.

On the street its safe to go with the most cubes you can reasonably achieve.

[vinniekq2]

Originally Posted by ap72

A 350 and a 383 will have very close peak power levels but the power will come in early with a 383, which means less RPM which is usually what you want on the street. Same thing with a 302 chevy vs a 383 chevy, about the same peak power but the 302 will have to rev higher to make it which means the valve train will take more abuse.

On the street its safe to go with the most cubes you can reasonably achieve.

before this gets out of hand:

what AP72 says is true if the same parts are used in each engine

If you compare maximum power potential,then the bigger engine will make more power

[ap72]

Originally Posted by vinniekq2

before this gets out of hand:

what AP72 says is true if the same parts are used in each engine

If you compare maximum power potential,then the bigger engine will make more power

that all depends on what is limiting power.

Often RPM is the limiting factor, because of the valvetrain, not the rotating assembly, if that is the case then obviously the 383 will make more power. If both are held to 7,000 RPM to get away with a fairly low cost valve train then the 302 or 350 wouldn't have a chance against the 383.

I'm building a 302 chevy, but besides just being different a large part is because I'm also running a fairly stock WC T5 trans which can't take the torque a 383 will produce.

[spinn]

Originally Posted by ap72

A 350 and a 383 will have very close peak power levels but the power will come in early with a 383, which means less RPM which is usually what you want on the street. Same thing with a 302 chevy vs a 383 chevy, about the same peak power but the 302 will have to rev higher to make it which means the valve train will take more abuse.

On the street its safe to go with the most cubes you can reasonably achieve.

That is not a very true statement. If they are built at the same level internally, then its flat wrong.

I have never stroked or destroked a build. Just built a 350 with the performer package and a 305. Similar build the 350 made more hp and torque. The 283 and 307 is example with only stroke changing.

At same street level, size or forced pressure makes a difference. If you are discussing engine potential about how, if it could be done, the peak would be similar.

[strokermax]

just add a blower and call it a day lol. just messing im interested in this actually

[oldbogie]

Originally Posted by demarques_191

I have read many hotrod magazines, read through forums and seen so many people post HP and TQ numbers of what 355's can put out identical power or close to it... Well the torque was down some but... The 355 would basically need a little more compression than the 383? opinions... opinions...

Check the RPMs where the power peaks occur. It all gets into how much fuel and air can you pump through the thing. A smaller engine has to turn more often than a larger engine to pump the same amount of air and fuel to make the same peak torque and horsepower numbers. Certainly the efficiencies of the parts need to be equal to the task to show this.

Bogie

[bigblockragtop]

No replacement for displacement, except maybe nitrous, blower or turbo, but that is another thread

[ap72]

Originally Posted by bigblockragtop

No replacement for displacement, except maybe nitrous, blower or turbo, but that is another thread

or RPM.

Those tiny displacement F1 engines will put most circle track engines to shame on the dyno, but they are revving around 20,000 RPM now.

Hell even the import guys are getting Honda 4 bangers and the like into the 400hp range NA, and buzzing to the moon to do it.

[68NovaSS]

Originally Posted by ap72

or RPM.

Those tiny displacement F1 engines will put most circle track engines to shame on the dyno, but they are revving around 20,000 RPM now.

Hell even the import guys are getting Honda 4 bangers and the like into the 400hp range NA, and buzzing to the moon to do it.

Yep, limited to 18,000 rpm, they were cramming 450 litres of air per second into a little 2400 cc motor, 146 c.i. and making around 1,000 hp. After 2005 regulations required 2.4 litre V-8 motors and power dropped about 20%.

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