340 Vs 360

[justinp61]

Don’t worry, the Chevy guys are laying that just for the rockers never mind what they mount to and… and!!!!

Make them work right.

Yep! Ahead of the curve yet again…..

A few years ago some (Chevy) guys I know were trying to get a heads up class for street/strip cars. I stopped by one of the guys shop and several others were there discussing probable rules. One of the rules was going to be no “shaft mounted rockers”. I sat and listened a bit, then mentioned that the rocker rule would eliminate all the Mopars because they came from the factory with shaft mounted rockers. The reply I got was “oh well, it sucks to be a Mopar guy”. The class never got off the ground because the rules eliminated in one way or another pretty everyone but that little clique.

 

[Ironracer]

lol i won alot of money street racing my 318 with spray
in a model 270 dart
people thought it had 273
chevelles gto vettes mustangs easy money
spray right off the hit

HECK YEAH!!!!!!!

 

[273]

You're right that horsepower is what moves the car.
Horsepower = Torque x RPM / 5,252

But RPM can't be king. Neither can torque.
It takes both.
Taking one variable in an equation and calling it "the king" doesn't work, that isn't science.

My issue with "rpm is king of horsepower" is that it's just the reverse argument of "torque is king of horsepower"

They're both neglecting the importance of the remaining part of the equation.

Let's really bench-race here.

If you built 21 different small block mopar engines, all with the same compression, cylinder head, cam, intake, etc.

All with an equal bore, let's say 4.04"
But each one had a different stroke length.

1st) with 4.00" stroke
2nd) with 3.900" stroke
3rd) with 3.800" stroke
4th with 3.700" stroke
..etc
...etc
21st) with 2.00" stroke

The biggest engine is a going to displace 410ci, the smallest engine is a 205ci

Do you think *any* of the smaller engines could ever realistically create more horsepower than the larger 410ci with the 4.00" crankshaft?

A 410 vs a 305 would more realistic, at similar lbs-ft:cid a 8,000 rpm 410 would be about a 11,000 rpm 305, why same top end? say you base the parts on a 11,000 rpm 305 probably won't work so well on the 410 and vice versa, it's hard to do apple to apple comparison since each combo needs to be tailored for each application. So what's apple to apple if different parts are required ? What it takes to make same hp? Other?

 

[273]

I wonder at what rpm a longer stroke becomes a handicap. Guys like Brett Miller are building high rpm small blocks with longer 4"ish strokes that make huge power and are routinely turned 8500-9000 rpms.

Probably more of an issue for things like land speed, endurance etc.. They do seem to be getting to a point where piston speeds are so high practical rpm is becoming the limiting factor.

 

[frosty_the_punk]

A 410 vs a 305 would more realistic, at similar lbs-ft:cid a 8,000 rpm 410 would be about a 11,000 rpm 305, why same top end? say you base the parts on a 11,000 rpm 305 probably won't work so well on the 410 and vice versa, it's hard to do apple to apple comparison since each combo needs to be tailored for each application. So what's apple to apple if different parts are required ? What it takes to make same hp? Other?

The point of that bench racing comparison with multiple strokes was to demonstrate that RPM *isn't* "king of horsepower".

Incrementally reducing stroke will require you to run more RPM (and usually more cam duration) to achieve the same horsepower but it sure-as-**** won't make *more* horsepower.

As a general rule, whenever you are working on an engine platform with multiple different displacement offerings available, and top end and valvetrain components are interchangeable between.

The best practice for making horsepower is to start with the biggest displacement you can. And build from there according to the required application.

There may be the occasional exception to the rule, but it's extremely rare to increase potential horsepower by reducing displacement.

 

[rumblefish360]

The rpm advantage of stroke, pistons speed for most don't come into play especially if we're talking same crank material.

Really? Crank material has a play in RPM?

That’s a new one on me.

It's head flow a 360 is gonna need more port to turn the same rpm as a 340.

At what level of RPM?

There one thing were leaving out is a 360 is less than 6% bigger, even though torque is tied to displacement in a narrow ish range but range* is huge enough that a 340 could make same even more torque just needs 6% + more in lbs-ft per cid .

So build the smaller engine up more than the bigger engine?

*1:1 to 1.6+:1 lbs-ft:cid

Street range power suggestions?

Just a quick question, was all of the above directed at me?

I ask because the quote is actually someone else’s statement. It got a little messed up when I replied.

A few years ago some (Chevy) guys I know were trying to get a heads up class for street/strip cars. I stopped by one of the guys shop and several others were there discussing probable rules. One of the rules was going to be no “shaft mounted rockers”. I sat and listened a bit, then mentioned that the rocker rule would eliminate all the Mopars because they came from the factory with shaft mounted rockers. The reply I got was “oh well, it sucks to be a Mopar guy”.

Typical asshat comment.
Buicks as well……

The class never got off the ground because the rules eliminated in one way or another pretty everyone but that little clique.

Typical!

 

[273]

The point of that bench racing comparison with multiple strokes was to demonstrate that RPM *isn't* king.

I don't think it is king but at least just as important as torque hp wise as torque, most seem to think or act like it's some kind of byproduct of little importance, since just about everyone is on the torque is king bandwagon. Instead of hp is a ratio of torque and rpm and different cids are gonna be a different ratio. Obviously efficiency comes into play and vary those ratios.

Incrementally reducing stroke will require you to run more RPM to achieve the same horsepower but it sure as **** won't make *more* horsepower.

Depends on the top end it's probably gonna favor one of them, not necessarily the largest one.

As a general rule, whenever you are working on an engine platform with multiple different displacement offerings available, and top end and valvetrain components are interchangeable between.

The best practice for making horsepower is to start with the biggest displacement you can. And build from there according to the required application.

For most builds I'd agree, but really it's goal dependent and if most followed that we all would have at least a 440 in our car, if 20 cid is s big deal between 340/360 than 32-80 plus got to be a bigger deal over 360/408.

There may be the occasional exception to the rule, but it's extremely rare to increase potential horsepower by reducing displacement.

I would say cause generally larger engines have larger bores.

 

[273]

Really? Crank material has a play in RPM?

Piston speed, Would you use a cast cranks for 10,000 rpm motor even a 8,000 rpm ?

Street range power suggestions?

If your building above 1.3 lbs-ft per cid your doing something right, 1:15-1.29:1 is decent average guy above 1.2:1 should be proud.

Just a quick question, was all of the above directed at me?

Nope Justinp61

 

[frosty_the_punk]

I don't think it is king but at least just as important as torque hp wise as torque, most seem to think or act like it's some kind of byproduct of little importance, since just about everyone is on the torque is king bandwagon. Instead of hp is a ratio of torque and rpm and different cids are gonna be a different ratio. Obviously efficiency comes into play and vary those ratios.

I agree, torque and RPM are equally important in making horsepower.

I do think though that for a car, sacrificing RPM to increase torque is a beneficial trade-off for increased performance. This is the appeal of a longer stroke.

If we were talking motorbikes, or go-karts.. sacrificing torque for an increased RPM may be more beneficial. Probably why diesel motorbikes aren't popular.

Depends on the top end it's probably gonna favor one of them, not necessarily the largest one.

I'm not really aware of any top end configuration that would make less horsepower by being bolted to a larger displacement engine.
Would you mind elaborating on this for me?

For most builds I'd agree, but really it's goal dependent and if most followed that we all would have at least a 440 in our car, if 20 cid is s big deal between 340/360 than 32-80 plus got to be a bigger deal over 360/408.

Having an additional 20ci is objectively an advantage.

Whether it's a "big" advantage is relative.
As you get closer to maxing out an engine's potential, the gains get exponentially smaller and cost exponentially more.

Let's imagine our A-body cars had mostly came with 440's from factory.

There would be very few people who would go to the effort and expense of swapping to a smaller, rarer small block engine which also takes a different transmission.
It'd be 440's all day and twice on sunday.

Now, let's instead imagine that you could go to a wrecking yard and pull a 440 from a 2001 ram with closed chamber heads, roller cam, 1.6 rockers and basically bolt all your factory accessories straight on to your 340ci engine.
Again, it'd be 440's all day!

I would say cause generally larger engines have larger bores.

You're right that larger displacenent engines usually have bigger bores, but I'm going to have to disagree that that bore size is the reason they have more potential.

The reason bigger displacement engines have more potential is that they are bigger displacement. And bigger displacement makes more torque.

 

[frosty_the_punk]

There is NO WAY you can build a series of engines with the same camshaft/valvetrain components in each engine to get the results that the stroke of the engine would require.

That 2" stroke engine is going to have to spin hard to make good HP. Like comparing a nascrap 358 engine that turns 8-9K and an F1 2.4L engine turning 18K while making the same peak 850 HP. One has a 3+ inch stroke the other about 1 5/8" IIRC. There is a reason that F1 cars have 7 speed gearboxes. If given the choice, F1 would run more ratios like 10. Keep the engine in the max power level at all time.

That's all true, but do you think the smaller stroke platform guys would be able to pretty much immediately make more horsepower if the rules suddenly allowed them to increase their engine's stroke and displacement?

 

[Rat Bastid]

What’s a Ritter block cost? It’s high end. If you don’t think so, please shine the light on me who has the better block that’s high end but yet not exotic. I’m all ears on this one for sure.

How about a MP R/R3 block for 600hp?

Myself and the forum would like to know what you think about what rod for what purpose?

Yup! It only goes so far. Far enough for a reasonable street car I think.

I like busting my Chevy friends chops when they say, “Inwas thinking about converting to a shaft rocker, what do you think “

Me; “Should have got a Chrysler because they came stock with that ****!”

IDK? I said high end and not exotic. To different categories to me.

A Ritter block is about 4k. And you know what? So is the equivalent SBC or Ford block. You can buy the lower grade blocks from Dart and such but to compare that block to a Ritter requires one to compare apples to apples. The day of the 2k SBC are over and 4k (or damned close to it) is what a quality SBC or Ford block costs.

The purpose of the rods is RPM. Isn’t that what we are discussing? You can buy a QUALITY connecting rod for under 500 bucks. Less than that if you shop around. I bet I can find a good 4340 H beam rod with 7/16 cap screws for 300 dollars. You can’t rebuild a set of stock rods for that, and they will STILL be 1018 steel with 3/8 bolts and nuts.

You can easily get a crank for under 1k that will take all the abuse you can give an NA engine. I beat the living **** out of stock cranks at 8500 and never broke one. And I was magnafluxing my stuff at least once a year. I also ran aluminum rods and didn’t use a rubber band damper.

Chrysler shaft rockers have a huge weak spot and there isn’t much you can do about it. And that’s the 5 3/8 mounting bolts. The Chevy guys get EIGHT 7/16 bolts to secure the rockers. That’s a big deal when you get to 9k and above. Those 5 bolts move around like a wet noodle.

What I just laid out was the truth about what it costs to use RPM. It’s no more expensive for the Chrysler guys when you compare equivalent quality of parts. You can buy cheaper Chevy blocks but even Dart will tell you their low end blocks are replacement blocks and not performance pieces.

The excuse is that it takes exotic or high end parts to make RPM worth doing just isn’t true, unless you are married to OE parts.

If that’s the case then what are we discussing? Are we talking about making horsepower or just mentally masturbating about things some of us don’t have any experience in?

 

[Rat Bastid]

I agree, torque and RPM are equally important in making horsepower.

I do think though that for a car, sacrificing RPM to increase torque is a beneficial trade-off for increased performance. This is the appeal of a longer stroke.

If we were talking motorbikes, or go-karts.. sacrificing torque for an increased RPM may be more beneficial. Probably why diesel motorbikes aren't popular.


I'm not really aware of any top end configuration that would make less horsepower by being bolted to a larger displacement engine.
Would you mind elaborating on this for me?


Having an additional 20ci is objectively an advantage.

Whether it's a "big" advantage is relative.
As you get closer to maxing out an engine's potential, the gains get exponentially smaller and cost exponentially more.

Let's imagine our A-body cars had mostly came with 440's from factory.

There would be very few people who would go to the effort and expense of swapping to a smaller, rarer small block engine which also takes a different transmission.
It'd be 440's all day and twice on sunday.

Now, let's instead imagine that you could go to a wrecking yard and pull a 440 from a 2001 ram with closed chamber heads, roller cam, 1.6 rockers and basically bolt all your factory accessories straight on to your 340ci engine.
Again, it'd be 440's all day!


You're right that larger displacenent engines usually have bigger bores, but I'm going to have to disagree that that bore size is the reason they have more potential.

The reason bigger displacement engines have more potential is that they are bigger displacement. And bigger displacement makes more torque.

Do you ever look at dyno graphs? If you did, you’d understand how whacked your first sentence is.

Go pull up a number a dyno graph and then explain to me how the HP curve is going up while the TQ curve is going flat and then down.

And once you do that, show me ONE power speed calculator that uses TQ to show MPH and ET. Just ONE.

 

[Rat Bastid]

That's all true, but do you think the smaller stroke platform guys would be able to pretty much immediately make more horsepower if the rules suddenly allowed them to increase their engine's stroke and displacement?

Nope. You have to have the induction to feed your displacement.

Adding stroke without accounting for air flow means you LOSE power. Every. Single. Time.

 

[Rat Bastid]

A few years ago some (Chevy) guys I know were trying to get a heads up class for street/strip cars. I stopped by one of the guys shop and several others were there discussing probable rules. One of the rules was going to be no “shaft mounted rockers”. I sat and listened a bit, then mentioned that the rocker rule would eliminate all the Mopars because they came from the factory with shaft mounted rockers. The reply I got was “oh well, it sucks to be a Mopar guy”. The class never got off the ground because the rules eliminated in one way or another pretty everyone but that little clique.

And those dumb asses THINK they are reducing costs by using stud mounted junk.

They love to step over donuts to grab a big handful of **** and then tell you how great that mouthful of **** tastes.

 

[Rat Bastid]

The point of that bench racing comparison with multiple strokes was to demonstrate that RPM *isn't* "king of horsepower".

Incrementally reducing stroke will require you to run more RPM (and usually more cam duration) to achieve the same horsepower but it sure-as-**** won't make *more* horsepower.

As a general rule, whenever you are working on an engine platform with multiple different displacement offerings available, and top end and valvetrain components are interchangeable between.

The best practice for making horsepower is to start with the biggest displacement you can. And build from there according to the required application.

There may be the occasional exception to the rule, but it's extremely rare to increase potential horsepower by reducing displacement.

I can tell you ain’t an engine builder. Any engine builder who has done this for very long will tell you RPM is KING. Because you don’t know it or understand it is a you thing.

I posted a link to the 2023 Engine Performance Expo. I doubt many watched it. But it’s free.

I suggest you spend some time looking at the EFI University LS build and then come back and say RPM isn’t KING.

 

[273]

I agree, torque and RPM are equally important in making horsepower.

I do think though that for a car, sacrificing RPM to increase torque is a beneficial trade-off for increased performance. This is the appeal of a longer stroke.

If we were talking motorbikes, or go-karts.. sacrificing torque for an increased RPM may be more beneficial. Probably why diesel motorbikes aren't popular.

Rpm doesn't have to be sky high taking a 360 peak hp from 4500 rpm to 5000 rpm is a good bump in power probably 50 ish hp same to 5500, 6000 and so on can build pretty good power under 6000 rpm.

I'm not really aware of any top end configuration that would make less horsepower by being bolted to a larger displacement engine.
Would you mind elaborating on this for me?

Different engines are gonna like different cam timings port shape intake exhaust etc.. The differences in a engine that makes from ok to great lbs-ft per cid. Off the shelf parts are gonna respond slightly differently to each and it maybe generally in favor of larger engines but I'd careful from saying always or even near always.

Having an additional 20ci is objectively an advantage.

That's basically what the factory did 170/198/225 318/340/360 350/361/383/400 383/413/426/440 each slightly more power than the one before keep peak hp rpm low

Whether it's a "big" advantage is relative.
As you get closer to maxing out an engine's potential, the gains get exponentially smaller and cost exponentially more.

Let's imagine our A-body cars had mostly came with 440's from factory.

There would be very few people who would go to the effort and expense of swapping to a smaller, rarer small block engine which also takes a different transmission.
It'd be 440's all day and twice on sunday.

I hope one day go from 360 to 470

Now, let's instead imagine that you could go to a wrecking yard and pull a 440 from a 2001 ram with closed chamber heads, roller cam, 1.6 rockers and basically bolt all your factory accessories straight on to your 340ci engine.
Again, it'd be 440's all day!


You're right that larger displacenent engines usually have bigger bores, but I'm going to have to disagree that that bore size is the reason they have more potential.

The reason bigger displacement engines have more potential is that they are bigger displacement. And bigger displacement makes more torque.

A 400 has a easier time than a 408, feeding high rpm high hp, but ya that's gonna be way up there, for the average not so much difference even a 273 bore is probably good for 400-425 hp without going with a super crazy build, so most bore 3.91 and up are big enough for what most people do.

 

[273]

Do you ever look at dyno graphs? If you did, you’d understand how whacked your first sentence is.

Go pull up a number a dyno graph and then explain to me how the HP curve is going up while the TQ curve is going flat and then down.

My guess is torque is somewhat flat runs horizontal ish but as an engine climbs in rpm the ve% start go down having a harder and harder time filling the cylinders even though torque is going down it's around 90% at peak hp so still a reasonable amount being multiplied by high number of powerstrokes as the torque continues to go down it starts to bring the power numbers down with it.

If torque stayed flat from say idle to redline hp would continuously rise in a straight diagonal line.

 

[frosty_the_punk]

Do you ever look at dyno graphs? If you did, you’d understand how whacked your first sentence is.

Indeed I do look at them.
Perhaps you could actually explain your position instead of just calling things "whacked" and accuse people of not having ever looked at a dyno graph?

Go pull up a number a dyno graph and then explain to me how the HP curve is going up while the TQ curve is going flat and then down.

That's the easiest thing in the world to explain, horsepower is dictated mathematically by torque and rpm. Hence why I said both of these things are important.

And once you do that, show me ONE power speed calculator that uses TQ to show MPH and ET. Just ONE.

I can't because torque only tells part of the story in the same way RPM only tells part of the story.

Can you show me a power speed calculator that uses RPM to predict MPH and and ET?

 

[frosty_the_punk]

Nope. You have to have the induction to feed your displacement.

Who's saying otherwise? Certainly not me.

Adding stroke without accounting for air flow means you LOSE power. Every. Single. Time.

Really, so if I add a 4" stroke to my 318 I'll end up with less horsepower than I started with?
I'm going to have to disagree there.

 

[frosty_the_punk]

I can tell you ain’t an engine builder.

Correct, I'm not. Are you?

Any engine builder who has done this for very long will tell you RPM is KING. Because you don’t know it or understand it is a you thing.

I'm not anti-RPM.
RPM is part of what it takes to make horsepower.
The other part is torque.

Neither can be king on their own.
I could put a 1200cc motorcycle engine in my valiant and it might rev to 12,000RPM or beyond

But it'll be slow. Because it won't make the horsepower of a 340 or a 360.

Are we really disagreeing on whether horsepower is the measuring stick for performance?

I posted a link to the 2023 Engine Performance Expo. I doubt many watched it. But it’s free.

I suggest you spend some time looking at the EFI University LS build and then come back and say RPM isn’t KING.

Would love to watch it, is that link somewhere in this thread?

 

[Rat Bastid]

Who's saying otherwise? Certainly not me.


Really, so if I add a 4" stroke to my 318 I'll end up with less horsepower than I started with?
I'm going to have to disagree there.

Build that 318 with a 4 inch stroke and it will make more power than it did BUT you won’t have enough cylinder head on it. It’s IMPOSSIBLE.

Think about it.

The W2 head was developed in the early 1970’s and was for 330 inch drag stuff and 355 inch circle jerk stuff.

And for those displacements and rod to stroke ratios they were too small. They take an incredible amount of work.

So you tell me, how is that a good thing using a 4 inch stroke and being THAT cylinder head limited because I’m thinking if you are starting with a 318 you won’t front for W2 heads?

You will be severely RPM limited unless you run outrageous cam timing.

Here is an example. This may help you understand.

In 2000 I built a 408. It had fully ported Edelbrock heads and a fully ported Strip Dominator. IIRC it was 10.8:1 but it could have been a skosh higher. It had a custom Cam Motion hydraulic roller that IIRC was in the low 240’s @ .050 and was in the low to mid .500’s for lift. It had a 750 Holley and 1 7/8 headers.

And guess what? At 5200 it was OVER. Used up. No more. It’s tongue was out and bloody.

We could have used more cam but then it would have needed more RPM (which is taboo) and it would have lost some bottom end (another fallacy).

It made 545 HP and I forget the TQ because who cares? It was close to the HP or maybe it was more.

Here‘s the real pisser. I would have built it with a 3.58 stroke (or maybe the 3.79 stroke as either would have been better than the 4 inch arm) and instead of the anemic 5200 RPM I would have turned the 365 inch (3.58 stroke) 7200 or the 387 incher (3.79 stroke) 6500ish and I could make the same 545 HP but at the higher RPM and the smaller engine would kick the living **** out of the 408. Every. Single. Time.

Understanding the math of it is relatively simple. Dealing with the facts is the hard part evidently.

 

[Rat Bastid]

Correct, I'm not. Are you?

I'm not anti-RPM.
RPM is part of what it takes to make horsepower.
The other part is torque.

Neither can be king on their own.
I could put a 1200cc motorcycle engine in my valiant and it might rev to 12,000RPM or beyond

But it'll be slow. Because it won't make the horsepower of a 340 or a 360.

Are we really disagreeing on whether horsepower is the measuring stick for performance?


Would love to watch it, is that link somewhere in this thread?

Hang on and I’ll go find it. There is also 3 more of them from years past. Once you have the link for this year you should be able to find all the other years.

They are worth every second if you want to learn from the best minds in the industry. And it’s FREE!

And yes, I used to build engines. I can still do it if I want to.

 

[Rat Bastid]

Correct, I'm not. Are you?

I'm not anti-RPM.
RPM is part of what it takes to make horsepower.
The other part is torque.

Neither can be king on their own.
I could put a 1200cc motorcycle engine in my valiant and it might rev to 12,000RPM or beyond

But it'll be slow. Because it won't make the horsepower of a 340 or a 360.

Are we really disagreeing on whether horsepower is the measuring stick for performance?


Would love to watch it, is that link somewhere in this thread?

Here is 2023 day 1. There are links to day 2 and the rest of them right there.

 

[frosty_the_punk]

Rpm doesn't have to be sky high taking a 360 peak hp from 4500 rpm to 5000 rpm is a good bump in power probably 50 ish hp same to 5500, 6000 and so on can build pretty good power under 6000 rpm.

Agreed.

Different engines are gonna like different cam timings port shape intake exhaust etc.. The differences in a engine that makes from ok to great lbs-ft per cid. Off the shelf parts are gonna respond slightly differently to each and it maybe generally in favor of larger engines but I'd careful from saying always or even near always.

I understand this concept of matching a top end to a specific cubic inch displacement, it seems very theoretical to me though.

I could understand how it might be applicable in perhaps an extreme rpm formula 1 engine at 20,000RPM where everyrting is voodoo to guys like me.

Not so much for a pushrod V8 that won't even see 8000RPM in either the bigger or smaller configuration.

In practice I'm not aware of nor have I ever witnessed any situation where increasing to a larger displacement bottom end configuration was detrimental to horsepower output.

If you know that this can indeed be the case, Would it be possible to provide me with an example?

That's basically what the factory did 170/198/225 318/340/360 350/361/383/400 383/413/426/440 each slightly more power than the one before keep peak hp rpm low

Precisely. It's far more economical to improve performance by increasing torque through larger displacement than it is to increase performance by developing the top end and valvetrain of a given displacement engine to carry it's torque into a higher RPM.

I still think any cylinder head thst makes good horsepower on a 340 will make a little more on a 360.

I hope one day go from 360 to 470

A 400 has a easier time than a 408, feeding high rpm high hp, but ya that's gonna be way up there, for the average not so much difference even a 273 bore is probably good for 400-425 hp without going with a super crazy build, so most bore 3.91 and up are big enough for what most people do.

Agreed, a 400 B engine has entirely different architecture to that of a 408 stroker small block and more horsepower potential.

Engine masters did an excellent test on a 383 mopar big block compared to a 383 chev small block and the small block got roasted, presumably coz big block the top end is intended to support 440ci+

 

[273]

Agreed.


I understand this concept of matching a top end to a specific cubic inch displacement, it seems very theoretical to me though.

I could understand how it might be applicable in perhaps an extreme rpm formula 1 engine at 20,000RPM where everyrting is voodoo to guys like me.

Not so much for a pushrod V8 that won't even see 8000RPM in either the bigger or smaller configuration.

In practice I'm not aware of nor have I ever witnessed any situation where increasing to a larger displacement bottom end configuration was detrimental to horsepower output.

If you know that this can indeed be the case, Would it be possible to provide me with an example?

You need to look at high end builds but it's not necessarily in what parts they use but they do with them, here one build that fits the bill an engine master competition motor not the show but an actual competition, it's a 360 bored to 371 making 515 hp @ 6000 rpm's and 495 lbs-ft @ 4800 rpm and over 400 lbs-ft 2500-6500 rpm, that's the torque of larger like a 408, and hp at reasonable rpms. Pretty sure this is one of the builders on here.

371ci Mopar Small Block - Popular Hot Rodding Magazine