How does cid make power?

[Cheapsunglasses]

That's true, but then they should look at the e.m. episode with the 383 Chevy vs the 383 Mopar. Peak hp and torque, virtually identical. The mopars torque bulge in the midrange was HUGE.

That enforces my statement. Also why you can’t just go by dyno #’s. You look at peak dyno #, they’re the same. Put them in similar cars, I’d bet the mopar torque would embarrass the cheby. This is why engines are so much fun

 

[33IMP]

That enforces my statement. Also why you can’t just go by dyno #’s. You look at peak dyno #, they’re the same. Put them in similar cars, I’d bet the mopar torque would embarrass the cheby. This is why engines are so much fun

I'll bet the Chevy would need 3.73s to run with the Mopar with 3.23s. Mopar big block live off torque. Cause like Brule says, it's a big block with a small block cylinder head.

 

[Cheapsunglasses]

I'll bet the Chevy would need 3.73s to run with the Mopar with 3.23s. Mopar big block live off torque. Cause like Brule says, it's a big block with a small block cylinder head.

There was another episode of engine masters that proved that, can’t remember which one. Even Dulcichs mild 440 saw a major improvement in the entire rpm range with max wedge heads

 

[rumblefish360]

There was another episode of engine masters that proved that, can’t remember which one. Even Dulcichs mild 440 saw a major improvement in the entire rpm range with max wedge heads

Like I always said… Freiburger as well, get the best cylinder head you can afford on top.

 

[Cheapsunglasses]

Like I always said… Freiburger as well, get the best cylinder head you can afford on top.

Goes back to what I said, and many others. Engines are air pumps, they need to breathe, yes cubic inches is factor. But you can do anything you want as far as cubic inches goes, any manifold or header. Any intake, or power adder. If you ignore your cylinder heads, you’re not using your full potential, and frankly wasting your time.

The old way of thinking was bigger is better. Now through research, all it takes is a good set of heads, a good intake, a good cam, and a good set of headers, and you can have a pretty potent engine.

Weather you like him or not, Freiberger really saved the car hobby.

 

[Rat Bastid]

That enforces my statement. Also why you can’t just go by dyno #’s. You look at peak dyno #, they’re the same. Put them in similar cars, I’d bet the mopar torque would embarrass the cheby. This is why engines are so much fun

Damn. How big was the bore on the Chrysler? And what was the bore on the Chevy?

Then compare the torque curves.

 

[66fs]

Airflow is horsepower, displacement keeps the rpm in the survival range.

 

[273]

A shame…. You were getting really funny with the pictures.

What your looking at is the HP @ peak and calling it the final factor in the decision. This is short selling the stroker. Ultimately, the bore size is the limitation on HP being able to be made. The stroke increase is for torque. Since your increasing the cubic inches, the possibility of more HP is possible even with the same bore size but yet still limited because of it.

Being that stroke is increase to make more torque, the HP will increase in all areas as long as the torque is superior against the stock or lesser stroke engine. This is where your he win is.

Unless the engine size becomes vastly different, the change in rpm peak to peak is small. You listed this yourself and claimed it was huge until you seen different but still called the 300 rpm change large, which then called for a gear ratio and/or tire size change. This would inky be needed in the maximizing of the vehicle in a drag race.

I'm not just looking at the peak, again here the under the curve if you lined up the peaks like you would if gearing properly. It basically the same if you don't agree you don't agree I don't what more I can show. Not saying this happens with every combo but you line up the curve there's gonna be less real gain or losses.

410 3000=250 3500=310 4000=365 4500=399 5000=420 5500=431hp
360 3300=252 3800=315 4300=360 4800=399 5300=418 5800=423hp

Cid, lbs-ft, 1st rear , torque to tires
410 480 2.45 x 3.73 = 4386 lbs-ft
360 444 2.44 x 3.91 = 4253 lbs-ft

 

[33IMP]

Damn. How big was the bore on the Chrysler? And what was the bore on the Chevy?

Then compare the torque curves.

383 Chevy was a Blueprint short, so I think 4.030/3.75. The Mopar was +.060 (if I remember right), and actually 391. (Eight cu.in don't mean dick, imo), so 4.310/3.38.
So, more bore, less stroke for the mope, and still killed the chevies torque.
Edit Chevy was .040, so 385, mope was .060, so 394.

 

[273]

Airflow is horsepower, displacement keeps the rpm in the survival range.

That’s how I basically look at that top end for power and displacement for where you want that power to happen.

 

[92b]

That enforces my statement. Also why you can’t just go by dyno #’s. You look at peak dyno #, they’re the same. Put them in similar cars, I’d bet the mopar torque would embarrass the cheby. This is why engines are so much fun

If you're at a dyno and they are only giving you peak numbers then ask them for a graph of the entire curve. Also have them pull the motor in the rpm range that you want data for. There is no good reason that I can think of to leave the dyno with just peak numbers unless that's all you want.

 

[273]

Your logic in this endeavor has been wildly inconsistent.

The question was does CID make horsepower. The answer is absolutely.
The secondary question is whether a comparable engine with more CID will make more HP, and the answer is still absolutely.
The tertiary questions is whether the larger engine will make more PEAK HP, and that's a lot more complex because flow will dictate the rpm range for both, and the answer would depend on WHAT RPM you want the power compared at.
The quaternary question is whether it makes financial sense to increase the CID for more power, and the answer is again complex. If you have a bad-*** top end, then yes - make more CID. If your 273 peaks at 4500 rpm, you probably need to open your wallet for a better set of heads first.

There is no blanket answer for whether CID makes HP in ALL cases because that game is too easy to rig. At what RPM? What is the goal? Where is the torque needed?

A bigger bore wins in every case, but that's physically constrained by the engine design (bore centers). Stroke is the only other way to increase CID once bore is maxed out - but the question isn't about stroking vs boring, it's CID vs CID - and in general more is better unless there's other factors crippling the performance already. If the CID of a PERFORMANCE engine is increased and power doesn't increase, then something else (tight wallet) is holding the engine back - not the CID.

Let's attack this from a different angle, with torque everyone knows it's heavily related to displacement but top end does have some impact like with ve%, efficiency like from chamber shape etc.. The size of the cylinder has the biggest effect why we know a 440 will make more torque than a 273 100% of the time without any other info but with hp you'd need know whats done to these engines.
Cause yes displacement has an effect on hp but it's airflow and how high of an rpm the airflow will carry matters more.

So does say two engine same bore different displacement with same or similar level of top end heads cam etc.. Does the larger displacement always come out on top when laying power curves on top of one another? And if does why how?
Cause if displacement wins every time what is stopping the smaller engine turning enough rpms to make up the difference?

 

[273]

If you're at a dyno and they are only giving you peak numbers then ask them for a graph of the entire curve. Also have them pull the motor in the rpm range that you want data for. There is no good reason that I can think of to leave the dyno with just peak numbers unless that's all you want.

It's not about peak hp but you do have to overlap two engines with different powerbands to get what's going on especially in a drag race where both would be setup for optimal e.t./mph.

 

[rumblefish360]

If you ignore your cylinder heads, you’re not using your full potential, and frankly wasting your time.

Correct to a point and only because taking advantage of the best cylinder head is t always an option. Be it rules of the class or wallet thickness, making the max is t on everyone’s list.

The example I can give here is the popular Edelbrock or TF commonly chosen which work well for the power output most seek and there attractive price is nice or did they waste it all by not purchasing a Victor head?

Is the power worth the expense?
That’s a personal choice made and judged by the person owning and building the engine for what there doing.

The old way of thinking was bigger is better. Now through research, all it takes is a good set of heads, a good intake, a good cam, and a good set of headers, and you can have a pretty potent engine.

I disagree because adding a great set of heads to any displacement should be done. The bigger engine is the power winner every time.

Edelbrock, TF or the Victor, no matter what engine size there on, they’ll improve it.

Weather you like him or not, Freiberger really saved the car hobby.

Love the Frei-Guy.

 

[rumblefish360]

displacement keeps the rpm in the survival range.

I Disagree.
It is a combo of camshaft and valve spring.
The correct combo can spin a 4.50 crank 10K. Or just to 4500 for you RV.

 

[rumblefish360]

I’m traveling in a car and can only read and type so much but I’ll get back to you tomorrow. ;)

I'm not just looking at the peak, again here the under the curve if you lined up the peaks like you would if gearing properly. It basically the same if you don't agree you don't agree I don't what more I can show. Not saying this happens with every combo but you line up the curve there's gonna be less real gain or losses.

410 3000=250 3500=310 4000=365 4500=399 5000=420 5500=431hp
360 3300=252 3800=315 4300=360 4800=399 5300=418 5800=423hp

Cid, lbs-ft, 1st rear , torque to tires
410 480 2.45 x 3.73 = 4386 lbs-ft
360 444 2.44 x 3.91 = 4253 lbs-ft

 

[Cheapsunglasses]

Correct to a point and only because taking advantage of the best cylinder head is t always an option. Be it rules of the class or wallet thickness, making the max is t on everyone’s list.

Ok now you’re just throwing other variables, but I guess it’s my fault, I should have used the phrase I’ve used a lot. “Typically”

 

[rumblefish360]

Ok now you’re just throwing other variables, but I guess it’s my fault, I should have used the phrase I’ve used a lot. “Typically”

Naaaaaa, just sayin….. LMAO

For all out power in making the max?

You dead ringer right!!!!!

 

[66fs]

That’s how I basically look at that top end for power and displacement for where you want that power to happen.

You are trying to over simplify a very complicated thing. You can have a 291 Desoto Hemi, 3.72 bore and 3.344 stroke, in a rail run 200+ mph in the quarter, naturally aspirated. You can have a 71 340, 4.04 bore and 3.312 stroke, Duster run 102 mph in the quarter mile. Part has to do with weight the other is efficiency of the engine and what rpm you can run. rpm can be limited by oiling, valve train, component strength, ignition, fuel, intake, exhaust, aerodynamics, and I'm sure I'm forgetting more. In a typical engine power is not linear, a stock 340 and 273 hit 3,000 rpm and really start pulling hard. It is also helpful to know the intended use of the car. I'm not going to drive a drag race car on the street. I'm not sure what you are looking for in this exercise?

 

[66fs]

I Disagree.
It is a combo of camshaft and valve spring.
The correct combo can spin a 4.50 crank 10K. Or just to 4500 for you RV.

I disagree, much more complicated than that. And I'm not talking about a 7 second wonder that only runs the quarter mile at a time.

 

[Rat Bastid]

I Disagree.
It is a combo of camshaft and valve spring.
The correct combo can spin a 4.50 crank 10K. Or just to 4500 for you RV.

But the 4.50 will need a HUGE cross section intake port, a highly tuned exhaust port and cam timing to get there.

Not even a Pro Stock head can feed that at 10k. So you need to be looking at 9* MBE heads and things like that.

Plus, you’d have to look at BMEP and VE after peak torque.

 

[rumblefish360]

I disagree, much more complicated than that. And I'm not talking about a 7 second wonder that only runs the quarter mile at a time.

But the 4.50 will need a HUGE cross section intake port, a highly tuned exhaust port and cam timing to get there.

Not even a Pro Stock head can feed that at 10k. So you need to be looking at 9* MBE heads and things like that.

Plus, you’d have to look at BMEP and VE after peak torque.

The both of you are right and my comment is not in the example of 273’s use of everything, the top stock from one engine to the next for comparative purposes.

We must keep the stock heads for this talk and not the threads title and question!

No worries! Freiburger answered his question with a lie Print 598 stroker big block that used stock 454.
LMAO!!!!

But pay no attention to the second half of the episode.

 

[273]

You are trying to over simplify a very complicated thing.

I’m trying to complicated this subject, the ones saying “no replacement for displacement” are over simplifying the subject.

I'm not sure what you are looking for in this exercise?

Most Everyone says if you add displacement you automatically adds hp, now we all now that statement is true when it comes to torque since I’d say cid makes up at least 80% of torque. But the same can’t be said of hp far as I can see, yes displacement plays a part, but going from a 273 to a 360 amount cid ain’t automatically gonna give you X amount of hp like it would with torque. So I’m asking people to prove, show, explain how cid makes hp, since most think it does.

 

[rumblefish360]

I’m trying to complicated this subject, the ones saying “no replacement for displacement” are over simplifying the subject.

incorrect as I has been shown a million times via videos and the dyno’s

Most Everyone says if you add displacement you automatically adds hp,

100% true. IF the only thing you are looking at is the CID.

now we all now that statement is true when it comes to torque

100% true. IF the only thing you are looking at is the CID.

since I’d say cid makes up at least 80% of torque.

100% IF the only thing you are looking at is the CID.

But the same can’t be said of hp far as I can see,

Yes it is since HP is the result of torque. Increased displacement will increase torque. IF the only thing you are looking at is the CID.

yes displacement plays a part, but going from a 273 to a 360 amount cid ain’t automatically gonna give you X amount of hp like it would with torque.

Yes it will if it was a only looking at the cid only.
The parts of the engine will dictate how much HP will be delivered and how the curve comes in. Here is where you open up the argument to be subject to parts used. And the source of your argument.

So I’m asking people to prove, show, explain how cid makes hp, since most think it does.

Everyone (as far as I know) think it does except you.
It’s funny though because you say HP is from torque and torque pm. The more stroke, the more torque is added. The more rpm you give it, the more hp it makes, this you know and have shown but still say you don’t know the answer but there is your answer, you gave it yourself!
So now you know that you know.

 

[Rat Bastid]

incorrect as I has been shown a million times via videos and the dyno’s


100% true. IF the only thing you are looking at is the CID.

100% true. IF the only thing you are looking at is the CID.

100% IF the only thing you are looking at is the CID.

Yes it is since HP is the result of torque. Increased displacement will increase torque. IF the only thing you are looking at is the CID.

Yes it will if it was a only looking at the cid only.
The parts of the engine will dictate how much HP will be delivered and how the curve comes in. Here is where you open up the argument to be subject to parts used. And the source of your argument.

Everyone (as far as I know) think it does except you.
It’s funny though because you say HP is from torque and torque pm. The more stroke, the more torque is added. The more rpm you give it, the more hp it makes, this you know and have shown but still say you don’t know the answer but there is your answer, you gave it yourself!
So now you know that you know.

You missed one Rob. Horsepower is NOT the result of torque. It never is. It is the result of torque and RPM. You can have all the torque in the world and without RPM you have zero horsepower.

A quick look at a dyno graph shows this clearly. As torque starts to fall after its peak, the horsepower keeps going up. If you had to have torque to gain horsepower, once torque peaks and starts heading down (or even if it just went flat) you’d lose horsepower.

You absolutely can not ignore RPM in figuring horsepower. And without horsepower a car won’t move.