Why oh Why...

Who wants a Supercharged mouse when Chevy can make a Big Block?

:confused:

I wouldn't call a 6.2L a mouse.

Vortec 8100 (L18) 8.1L Big Block = 325HP/447tq

Vortec 6200 (L92) 6.2L small block = 403HP/417tq

LS7 427ci. 7.0L small block = 505HP/470tq

Even without the supercharger I'd take the small block, 6.0,6.2, or 7.0L

Why coulnd't you call a 6.2L a mouse? The difference between the mouse and rat motors wasn't the power rating but the physical size or the block and/or overall archtecture.

Where the cut off is between mouse and rat no ones been able to tell me, but if the 6.2 is an evolution of the 6.0 which has roots to the 5.7, then it's a mouse.

Getting back to the thread, I'd rather have a mouse motor. Lighter weight will mean much better chassis dynamics. Of course, I'm concerned with how the car handles at speed...not cruising the boulivard at 20 mph.

I think people should forget the days of the big block motor (besides in trucks). I will take a light all aluminum small block any day of the week.

Would a all aluminum big block weigh less then a Supercharged Ls9?

Why coulnd't you call a 6.2L a mouse? The difference between the mouse and rat motors wasn't the power rating but the physical size or the block and/or overall archtecture.

Where the cut off is between mouse and rat no ones been able to tell me, but if the 6.2 is an evolution of the 6.0 which has roots to the 5.7, then it's a mouse.

Getting back to the thread, I'd rather have a mouse motor. Lighter weight will mean much better chassis dynamics. Of course, I'm concerned with how the car handles at speed...not cruising the boulivard at 20 mph.

I forgot the mouse/rat motor terms. I thought he was just putting down the Gen IV small blocks compared to a big block.

It's cool.

Would a all aluminum big block weigh less then a Supercharged Ls9?

An interesting question I suppose. The power GM was--and is--making with its small blocks rendered the big block motor obsolete. However, if we're now going to supercharged small blocks, and the same power can be made with a N/A big block, you'd wonder if the BB could actually weigh less, thus making it relevant again.

Larger piston diameter tends to leave more unburned fuel, and therfore will be difficult to make emission compliant. For better or worse (depending on your vieew) the 60's and early 70's are gone. I would love to see LS style improvements to a true BB style platform, but I doubt we will ever see it.

Not all big blocks are as heavy as others.

For instance, a big block 455 from Buick weighs substantially less than a Chevy 454 (sorry, I don't have numbers). I think that I heard that it was barely more than an iron SBC.

Then again, you can get 472ci out of a small block, so unless you're planning on going even bigger than that, I'm all for the additional weight savings. :)

The Vortec 8100 has remained unchanged for quite a while. I imagine that GM could re-engineer a few things and get substantially more power out of it than the numbers in post #2.

You're right. the 8100 has a lot of potential...just swapping the exhaust and adding a tune gives you a noticeable difference....add in a different intake manifold, throttle body, maf, headers....you can easily got over 500 hp out of this bad boy...

call me ignorant for posting a noob question, but where is the cutoff btwn big and small blocks? Is it the switch from cast-iron to aluminum, a certain # of CIs, a certain # of litres, what?

To me, there is nothing small about a 7.0L LS7 bored to 427ci. I assume the line has been blurred by technological advancement, but hey, what do I know, as evidenced by my Q.

Who wants a Supercharged mouse when Chevy can make a Big Block?

I do, you can make same amount of power cheaper, more reliable and with better gas mileage.

You won’t be seeing any "big blocks" again in the Camaro.

call me ignorant for posting a noob question, but where is the cutoff btwn big and small blocks? Is it the switch from cast-iron to aluminum, a certain # of CIs, a certain # of litres, what?

To me, there is nothing small about a 7.0L LS7 bored to 427ci. I assume the line has been blurred by technological advancement, but hey, what do I know, as evidenced by my Q.
GM has two basic block designs, one "small" and one "big". Both blocks have a tremendous range of options in terms of bore and stroke. The small block supports a maximum bore and stroke of about 4.2", yielding 472ci in the largest configuration I've seen. There is very little room to spare in that setup. The "big block" supports displacements in excess of 600ci. The largest I'm aware of is in the 630ci-range, but I don't know how close to the limit that was.

All small blocks (from a given manufacturer) share the same bore spacing. Pretty much everything else can change, and it will still be a small block. Ditto for big blocks.

A big block is longer, taller, and wider than a small block.

I tend to agree..with the power yu can got from a small block, you really don't need a big block...if you want insane power, you can get it...it's been done...TT 427's in vette's for 1200+ hp worth...that should satisfy anyone...

I think people should forget the days of the big block motor (besides in trucks). I will take a light all aluminum small block any day of the week.

Many people think we should forget the days of v8 motors all together.

A well executed, freshly designed all aluminum big block would be a pretty awesome top of the line motor. Nothing beats big block torque, and this is coming from a "younger guy".

Then again, you can get 472ci out of a small block, so unless you're planning on going even bigger than that, I'm all for the additional weight savings. :)


You can make a small block a 500CI motor, but GM isn't about to do that anytime soon.

I tend to agree..with the power yu can got from a small block, you really don't need a big block...if you want insane power, you can get it...it's been done...TT 427's in vette's for 1200+ hp worth...that should satisfy anyone...

That should satisfy anyone who is happy running his car on race gas. There are NA big blocks out there turning 1000hp and running on pump gas.

Many people think we should forget the days of v8 motors all together.

A well executed, freshly designed all aluminum big block would be a pretty awesome top of the line motor. Nothing beats big block torque, and this is coming from a "younger guy".

Ok here is a better question….tell me how a big block is going to sell the 5th Gen anymore then the planned LS9/LS8/LS3 small block combo?

You can make a small block a 500CI motor, but GM isn't about to do that anytime soon.
500ci?

The biggest bore you can get out of a small block is 4.200". Many people would call you insane for going that high, let alone higher.

So let's assume you are only slightly insane, and you use a 4.200" bore. To hit 500ci, you need a 4.515" stroke. Modifications are required almost everywhere in the bottom end to handle a 4.250" stroke, and you're asking for a heap of trouble to go even higher.

I suppose it could be done, but if you need that kind of displacement, a big block is probably right for you. :)

Nothing beats big block torque, and this is coming from a "younger guy".
The size of the block has nothing (directly) to do with the torque. Nothing beats big cube torque.

OK, even on pump gas you can get 725 hp easy...compare that against a 8100 w/ a Whipple SC (good for ~700 hp)...let's just call them even in hp...now, compare the weight & size (packaging) differences...i wouldn't even try to stuff that blown 8100 into a car...

idk bout you guys but i rather have a like a 540ci big block puttin out like 600+hp then a supercharged mouse.. an they probably weigh the same 2. Then it would be different then a GT 500... oh yea could you imagine throwing 4 grand on a supercharger for it? umm 1000hp with just a simple supercharger

Alright.....for me, my 76 T/A is getting a 572 BB, simply because it's a 76 T/A and I feel it needs a BB. My 5th Gen, for that matter....a BB would be out of place. Give me a SC SB and I'll be happy.....I suppose I can "settle" for and LS9 instead of and LS7 ;)

Why coulnd't you call a 6.2L a mouse? The difference between the mouse and rat motors wasn't the power rating but the physical size or the block and/or overall archtecture.

Where the cut off is between mouse and rat no ones been able to tell me, but if the 6.2 is an evolution of the 6.0 which has roots to the 5.7, then it's a mouse.

Getting back to the thread, I'd rather have a mouse motor. Lighter weight will mean much better chassis dynamics. Of course, I'm concerned with how the car handles at speed...not cruising the boulivard at 20 mph.

According to GM, the LSx series is a medium block. Their internal specs required a platform that could act as both a small block as well as a big block.

The LSx series has produced displacements of 346 ci, which used to fall under the small block category. The same series includes a 427 ci displacement, which used to fall under the big block category.

I think it is was PH who did a great test between an old school Chevy 427 and an LSx based 427. Not surprisingly, the LSx based 427 produced extremely comparable results in terms of torque, compared to a classic BB 427. The classic 427 started generating torque quicker than the LSx 427. However, the LSx 427 could spin up higher than the classic 427. The main difference was in the efficiency between the two engines. The LSx 427 was more than twice as efficient as the classic 427.

All in all, GM did wonders with the LSx series, and the platform is hardly dated, as it continues to be evolved, perfected and extended to address technologies such as DOD.

good point greg_nate...let's look at a ZL-1 vs. LS-7...both with tuned headers...the ZL-1 was good for aorund 585 hp (in the Berger camaro's)...and from what has been recently done with a LS-7 in a Solstice, it was also good for 585 hp...same output, but much different at the same time...both very desireable and something to drool over...

The size of the block has nothing (directly) to do with the torque. Nothing beats big cube torque.

Big cubes come from big blocks.

500ci?

The biggest bore you can get out of a small block is 4.200". Many people would call you insane for going that high, let alone higher.

So let's assume you are only slightly insane, and you use a 4.200" bore. To hit 500ci, you need a 4.515" stroke. Modifications are required almost everywhere in the bottom end to handle a 4.250" stroke, and you're asking for a heap of trouble to go even higher.

I suppose it could be done, but if you need that kind of displacement, a big block is probably right for you. :)

Biggest LS1 type blocks are I believe the World style blocks with a taller deck. 4.2" bore and 4.5" stroke. 496 cubes. Pretty close to 500 cubes.

Ok here is a better question….tell me how a big block is going to sell the 5th Gen anymore then the planned LS9/LS8/LS3 small block combo?

I never said it would. Could finds it's way into a Vette though.

Guys here are saying that the day of the big block is over and done with. We can get comparable power out of smaller style v8s. The guys saying that are pretty much mirror the thoughts of many import guys, why make a v8 when comparable performance can be gotten out of a smaller motor.

The point is nothing FEELS like a big block. And of course, as JakeRobb said, this is because they can support more cubes typically. It seems very unlikely we will be seeing GM push the LS1 style motors any further in displacement than 7 liters.

Thanks for the info, Jake.

I never said it would. Could finds it's way into a Vette though.

Guys here are saying that the day of the big block is over and done with. We can get comparable power out of smaller style v8s. The guys saying that are pretty much mirror the thoughts of many import guys, why make a v8 when comparable performance can be gotten out of a smaller motor.

The point is nothing FEELS like a big block. And of course, as JakeRobb said, this is because they can support more cubes typically. It seems very unlikely we will be seeing GM push the LS1 style motors any further in displacement than 7 liters.

I won’t argue with you that big blocks have a special cool feel to them. I’m a motor head too and even though I’m a young guy I think they are very cool.

But as a guy who analyses the auto industry on an ongoing basis, I just don’t see a market for them. I just don’t think they would sell enough to support the design.

I could go into details but you’re a regular around here so I assume you know what I’m talking about.

Thus the businessmen of GM would never approve something like this. Unfortunately GMs bottom line is money and not cool stuff for the enthusiast.
:D

According to GM, the LSx series is a medium block. Their internal specs required a platform that could act as both a small block as well as a big block.

The LSx series has produced displacements of 346 ci, which used to fall under the small block category. The same series includes a 427 ci displacement, which used to fall under the big block category.

I think it is was PH who did a great test between an old school Chevy 427 and an LSx based 427. Not surprisingly, the LSx based 427 produced extremely comparable results in terms of torque, compared to a classic BB 427. The classic 427 started generating torque quicker than the LSx 427. However, the LSx 427 could spin up higher than the classic 427. The main difference was in the efficiency between the two engines. The LSx 427 was more than twice as efficient as the classic 427.

All in all, GM did wonders with the LSx series, and the platform is hardly dated, as it continues to be evolved, perfected and extended to address technologies such as DOD.


Hmm, interesting. So what's between a mouse and a rat? ;)

Big cubes come from big blocks.
I don't know about you, but 472ci is pretty big in my book, and 496 with just a taller deck is friggin huge.

That said, I was at a car show the other day and there was a guy with a C3 Vette ('76 I think) with a tube frame, ZZ572 crate motor, TH400, and a 9" rear with Hoosier DRs. Engine dyno'd at 676hp on 93 octane. Absolutely badass. :cool: Funny thing was, he wanted to put a supercharger on it. :lol:

Hmm, interesting. So what's between a mouse and a rat? ;)

Maybe a chipmunk, or squirrel. Squirrel motor just doesn't seem to have the same ring to it

Mole motor!

Mole motor!

:lol:

I realize that this is in the 5th Gen forum, but Id like to ask this because there are hardly ANY Big Block threads on here, at least applying to new engines. Why hasnt GM made an awesome BB for their trucks? It seems that if they are able to get the 8.1 to pass emissions, they would be able to make a much better BB for maybe a hardcore performance version of the Silverado. Ive never actually been in a car with a BB, but from what ive heard from anyone who has or has owned one, its quite the experience to drive a hi po BB. To me it just seems like GM is not fully utilizing their knowledge gained from the LSx motors, they could be applying ALOT of it to BB's.

I realize that this is in the 5th Gen forum, but Id like to ask this because there are hardly ANY Big Block threads on here, at least applying to new engines. Why hasnt GM made an awesome BB for their trucks? It seems that if they are able to get the 8.1 to pass emissions, they would be able to make a much better BB for maybe a hardcore performance version of the Silverado. Ive never actually been in a car with a BB, but from what ive heard from anyone who has or has owned one, its quite the experience to drive a hi po BB. To me it just seems like GM is not fully utilizing their knowledge gained from the LSx motors, they could be applying ALOT of it to BB's.
GM does have an awesome big block -- it's called the ZZ572, and can be ordered from GMPP for about $13,000 making 620hp on pump gas. I've met one guy with one, and his made 670+ on an engine dyno. There is a more expensive race gas version (higher compression) which claims 720hp and is probably similarly underrated. These engines have relatively mild cams -- quite a lot more power is available if you don't need a streetable motor.

I imagine that there is very little demand from customers to get a motor like that in a truck in any sort of configuration you'd ever get from the factory. Therefore, GM just sells it in a crate, and the enthusiasts that would be interested in such a thing can install it and set it up any way they want.

Makes sense to me. :shrug:

Well yeah, I know they have the 572, I was talking about an engine they would actually put into a production truck. Something to compete with the SRT-10 Ram or the late Lightning.

Well yeah, I know they have the 572, I was talking about an engine they would actually put into a production truck. Something to compete with the SRT-10 Ram or the late Lightning.

This makes me wonder. Would you guys consider the 505CID Viper v10 a big block? I know big blocks are classically v8s, but it is a big cube engine.

This makes me wonder. Would you guys consider the 505CID Viper v10 a big block? I know big blocks are classically v8s, but it is a big cube engine.
I wouldn't, but I'm having trouble justifying my opinion. :shrug:

It just doesn't feel right.

I wouldn't, but I'm having trouble justifying my opinion. :shrug:

It just doesn't feel right.

I don't think you are the only one having trouble justifying that opinion. Most guys don't consider it a big block it seems, but besides having 2 more cylinders, it seems to meet most of the criteria for it.

In the Chevy and Ford worlds, I know that "small block" and "big block" are used to refer to V8 blocks with common basic layouts (bank separation angle and bore spacing).

I'm pretty sure the Mopar world has the same deal (I'm just not very well versed with Mopar stuff).

Does the Viper V10 have the same bank separation angle and bore spacing as, say, a 426 Hemi?

If it does, then you might convince me to call it a "big block".

In the Chevy and Ford worlds, I know that "small block" and "big block" are used to refer to V8 blocks with common basic layouts (bank separation angle and bore spacing).

I'm pretty sure the Mopar world has the same deal (I'm just not very well versed with Mopar stuff).

Does the Viper V10 have the same bank separation angle and bore spacing as, say, a 426 Hemi?

If it does, then you might convince me to call it a "big block".

The seperation angle in the Viper v10 is 90 degrees, and the bore spacing is 4.46" I believe. Not 100% sure on that though.

In the Chevy and Ford worlds, I know that "small block" and "big block" are used to refer to V8 blocks with common basic layouts (bank separation angle and bore spacing).

I'm pretty sure the Mopar world has the same deal (I'm just not very well versed with Mopar stuff).

Does the Viper V10 have the same bank separation angle and bore spacing as, say, a 426 Hemi?

If it does, then you might convince me to call it a "big block".

in the mopar world, the old school small blocks are the "A" engine line, big blocks are "B/RB" line(some are B, and rhe larger ones are RB(for raised deck B))

A few notes on why you won't see a big block in the 5th gen:

Packaging. Have you compared the external dimensions of a big block to an LS small block? The N* takes up about the same amount of room and likely GM won't leave room under the hood to hold the N* so there goes that arguement.

Now compare the new 6.2 Gen IV V8 to the 8.1 BB. The new 6.2 makes 403 hp at 5700 rpms and 417 ft/lbs at 4300 rpms. The current 8.1 makes 330 hp at 4200 rpms and 450 ft/lbs at 3200 rpms. In trucks for towing the 8.1 woluld be my choice but not over the Duramax with its 360 hp at 3200 rpm and 650 ft/lbs at 1600 rpms!

Fuel economy also plays a big role in the decision, remember CAFE?
The new 6.2 is estimated at 13 mpg city, 20 mpg highway for the RWD Escalade. I can't find estimates on the big block because 2500 and 3500 models aren't rated on Chevy's website but I can guess the highway mileage goes down quite a bit and I would also venture to guess that the city does as well. I will guess somewhere around 10 mpg city, 17 mpg highway.

a V10/V12 would be better than a Big Block for emissions. Too bad the LSx V10 got cancelled. 7.5L V10 Camaro would be cool, 600HP:metal:

guys we cannot compare the 8.1 liter from the trucks to the ls series small blocks.. the 8.1 is just a old style truck motor what you should be thinkin about is how a 8.1 liter ls big block would be like

A few notes on why you won't see a big block in the 5th gen:

Packaging. Have you compared the external dimensions of a big block to an LS small block? The N* takes up about the same amount of room and likely GM won't leave room under the hood to hold the N* so there goes that arguement.

Now compare the new 6.2 Gen IV V8 to the 8.1 BB. The new 6.2 makes 403 hp at 5700 rpms and 417 ft/lbs at 4300 rpms. The current 8.1 makes 330 hp at 4200 rpms and 450 ft/lbs at 3200 rpms. In trucks for towing the 8.1 woluld be my choice but not over the Duramax with its 360 hp at 3200 rpm and 650 ft/lbs at 1600 rpms!

Fuel economy also plays a big role in the decision, remember CAFE?
The new 6.2 is estimated at 13 mpg city, 20 mpg highway for the RWD Escalade. I can't find estimates on the big block because 2500 and 3500 models aren't rated on Chevy's website but I can guess the highway mileage goes down quite a bit and I would also venture to guess that the city does as well. I will guess somewhere around 10 mpg city, 17 mpg highway.

I usually get 10-11 mpg regardless of city or highway...when you step on the gas, you can literally hear a sucking sound...and with a 34 gallon tank, it's pricey to fill up...definately not a daily driver...but great truck engine nonetheless...

you can literally hear a sucking sound...
That'd be the air intake, with the turbocharger doing the sucking.

That'd be the air intake, with the turbocharger doing the sucking.
He has an 8.1 L V8 N/A, not turbo.

He has an 8.1 L V8 N/A, not turbo.
You can get an HD without the turbodiesel?

You can get an HD without the turbodiesel?

Yep...got the vortec 8100 in a 2500 HD ext cab w/ LB 4wd...great engine...has so much more potential than in stock form...in 2003, it was rated at 345 hp, 455 tq...so far, i've added a hypertech tune & gibson exhaust...next upgrade will be MAF, throttle body, air box, and intake manifold...

even in a vehicle with a massive curb weight, that thing will get up and move...just gets lousy gas mileage...

You can get an HD without the turbodiesel?
Yes the Duramax is at a limited production capacity.

I think the big reason we are seeing small blocks and supercharged small blocks is fuel efficiency. The LSx has already been proven to be 2x as efficient as an equivilant BB. This is not to say they couldn't take the technology of the LSx and build a comperable BB, but that would be a huge investment of money that a company in GM's situation can't afford to spend for the small ammount of return on that investment.

Also, gas guzzler taxes suck. Trucks are exempt which is why they can get away with those nasty BB engines.