blue86iroc

iTrader: (2)

Most of the time, you hear the usual "bigger is better" when talking about engine displacement. In the big-block world, two engines come to mind... the 396 and 454 (I'm leaving the 427 out, for now). Overall, which displacement provides for a better engine? Naturally, GM's 454 produced more power than the 396, but I would imagine that the 396 could rev higher due to smaller parts... sorta how a little four-cylinder can rev past 7000 RPM, when my L98 350 tops out at 5500 RPM.

What do you think?

Powerlover

How bout the best of both worlds.....427...Destroked 454.

SSC

They all rev about the same, its more a question of whats avalible. I persoanlly like 396's-402's for the simple fact they came with better parts stock IE domed pistons, most 396's you find used will have cam wear only! Leaving the block/pistons/crank in great shape, 454's will also have similiar cam wear but will most likely show more cylindar wall wear along with other damage. The last 3 402's I built (Excuding the rust bucket 396 enigne in my Chevell) were in perfect condition except for the cam, all I had to was run the ball hone through a couple times clean re-ring replace bearings and have the cranks cleaned and ground 10 under.

Ian_F

I would say the 396 is a better engine from the factory, but they aren't really popular for some reason. They are also less common than a 454. Why exactly are you leaving the 427 out? That is the best big block out of all of them. Remember the L-88. 500+HP all aluminum 427 :hail: . The 427 has a large bore and a short stroke. that makes for a very torquey and rev happy big block.

8Mike9

454, plain and simple.

The only reason to use a 396/402 or 427 is because that is what you may have on hand.

454's got a bad rap in the early to mid 70's when the smog/emissions took over.

five7kid

iTrader: (14)

396's were only made for 4 years (they actually grew to 402 in the 5th year). The spacing of the valves guarantees shrouding given the 4.096"/4.125" bore - doubly true if 2.19/1.88 valves are involved.

427 & 396 share the same stroke (which happens to be the same as the Mopar 440, and .01" longer than the SBC 400). A 454 is a stroked 427.

396/427's had steel cranks from the factory.

My block casting is the same one Chevy used for 2-bolt main 427's in '66.

I shift at 5700. My buddy's 10.9-sec 468 (.030"-over 454) Monte Carlo shifts at 6000. A fellow racer with a 13.4-sec '57 Nomad with 383 shifts at 6500 and goes through the traps at 6800. The money spent building the 383 and 468 was about the same. The 383 makes about 500 sea-level HP, the 468 ~650.

I am running a 396 because that's what I had. Pistons for 454s are less expensive, but I don't have one of those.

If you have a 396 shortblock and a 454 shortblock that need the same amount of "cleanup" to rebuild, the 454 will be faster for the same amount of money spent (assuming peanut heads aren't in the picture). Every time. A 454 that makes the same power as a 396 will out-last the 396.

Next weekend is the Super Chevy Show at Bandimere Speedway. At today's "normal" ET races, John Bandimere, Jr., got on the PA to talk that up. He stated that ~80% of the regular racers at Bandimere Speedway use a Chevy powerplant. I would guess over half of them are >454 CID. I have one of about 3 396's who race regularly (of which I am aware - and I notice things like that) - there was one other 4 years ago, but he trashed a cylinder (numbers-matching '66 Chevelle) - sleeved it, put it to the side, ran a 454 for 3 years, picked up a full second; put the 396 back in last winter and sold the car (sold the 454 to another racer buddy). Doesn't race anymore.

five7kid

iTrader: (14)

Ummm, what was the question again?

Morley

As mentioned, all big block engine parts had about the same weight and all reved about the same.

This was/is the height of big block power.

ZL-1 all aluminum 427.

Chevy's ZL-1 aluminum big-block is back--and it's better than ever! Introduced in 1969, the original ZL-1 was one of Chevrolet's rarest production engines. Now the improved and updated aluminum ZL-1 block is be available as P/N: 12370850.

Based on the original tooling, the new/old ZL-1 is cast from 356-T6M aluminum alloy and tips the scales at a scant 110 pounds. It's dry cylinder (cast iron) liners are bored to 4.250-inch diameter, that can be bored to 4.300". Its bottom end is bolstered with new four-bolt splayed steel main bearing caps, with splayed outer ball-tip studs.. All five main caps are accurately located and held in place with dowel pins, and the rear cap uses an early-style two-piece rear seal. Screw-in aluminum water-jacket plugs with O-ring seals add reliability.

The reborn ZL-1 block has provisions for both a dry-sump or regular oil pump systems and a mechanical fuel pump. The lightweight big-block is engineered to produce up to 800 hp with reliability, and it's aimed at vintage Can-Am racers, street rodders, nostalgia drag racers, and ZL-1 enthusiasts. All Gm performance cylinder heads will fit this block and it only weighs 110 lbs. The maximum stroke is 4.375".

Air_Adam

They are both good engines.. and some 396/402 blocks can be punched out to 4.25" to make 427ci.

The 396 parts are generally cheaper than 454 parts, for one thing. You could prolly get a decent forged 396 crank for about $100, but a forged 454 crank can cost more than alot of us paid for our cars, lol (no joke!)

There is a wrecker around here that is a good example... he sells just about any BBC but the 454 for about $600 (CDN)... he sells 454s (often i might add) for over $750, and they are in equal or worse condition than the 396/402s are.

Basically... if you really want the extra 58ci, you're gonna really pay for it...

89RsPower!

lol

blue86iroc

iTrader: (2)

Thanks for the replies, guys. I'm in the process of rebuilding a 396 for a 1967 Camaro SS-396 -- my father used to drag race the car and actually ran a ZL-1 at one point. I was looking through some old invoices and found the sales receipt for the motor. "Build full-competition 427 ZL-1: $1500." That was back in 1972. The fastest time he put down with the 396 was a 10.61, and I believe the 427 didn't go faster than low-11's.

I chose to leave out the 427 in my comparision because a friend of mine recently purchased a "fake" 1971 Chevelle SS-454 and was going on about how his 454 is so fast and wonderful, etc. The car put down a 15.77 in the quarter mile.

The 396 that's going in the '67 Camaro is going to be merely a street-performance motor, probably putting out around 400 horsepower. I'm not going to drag race the car, but I would like it to be fast, rather than just feel fast.

87daddyformula

I would say that if you are using it for street use it doesn't really matter which one you build...it only matters which one you want...the differences that everyone else is talking about only apply when you race, which you said you aren't going to be doing much...Chevy engines have been around long enough to have all the kinks worked out of them and people know what to expect and how to work on them...Truthfully, it doesn't matter in the least which one you build, just as long as you build it correctly and with good technique.

Good Motoring

25THRSS

The 396 all the way to the 427 all have the same stroke, with different sized bores. The 454 and the 502 both share the same stroke, with the 502 having a bigger bore obviously. Just get a 572, which is a bored and stroked 502, lol.

zippy

the 454. neither are limited on rev's. a 350 will rev as high as the valvetrain is going to hold up if it has the correct parts. same with the 396 and 454. they build 500 cubic inch pro stock engines that turn 9k plus so your 396 isn't going to be higher rpm due to it's size if you use the correct parts. whenever the question is cubes over rev's, go cubes...

Jim85IROC

iTrader: (2)

The 396 is just the 305 of the big block world. The reason a 4 banger revs so high is because it HAS to in order to make any power, and they have a much lighter rotating mass than a V8. A 396 has basically the same rotating mass as a 454.

I can't speak for reliability issues between the 396 and 454, but in terms of power, anything a 396 can do, a 454 can do better. It's the same as comparing a 350 to a 305. The biggest difference is that unlike a 305, at least the 396 still has a decent bore/stroke ratio.

Air_Adam

If its for a street-driven performance motor, I'd get the 396 and punch it out to a 427. That engine will cost probably $1000's less to build than a 454 will, and as far as street performance goes, you won't be able to tell the difference between a 427 and a 454 (power-wise)

Plus... I always thought it would be really cool to be able to say "Yea.. its got a 427 under the hood"

Rob116

BS, even if it is possible to bore a 396 to 427 (which I haven't heard before, would need some more confirmation before I believed it), it won't be any cheaper than building a 454 and the 454 will still run stronger than the 427 if comparable parts are used.

8Mike9

Why would you think it would cost 1000's less?

Do some pricing on parts...machine work is a wash...I think you'll see things differently.

blue86iroc

iTrader: (2)

The motor is staying a 396 because the car is originally an SS-396 Camaro -- about 1,000 of these were made in 1967.

five7kid

iTrader: (14)

'67 was the year the 396's started getting thinner cylinder walls. Made them lighter, but reduced the over-bore possibilities. Of course, the casting number will always say it's a "396", regardless of what it's punched to.

The crank is really the only thing that's cheaper for a 396 vs. 454, and only if you're talking about forged. And, performance heads for a 396 are non-existant - if you go open-chamber, you're going to have to get some big pop-up pistons to keep compression up, and "normal" 396 pistons are more expensive than 454 pistons. Even if you have to buy a shortblock, a 454 is going to be cheaper to build for the same power (as long as you don't think you need a forged crank).

Now that I understand that the question is building a 396 for street power (I guess), I think I've accomplished that. I haven't had it dyno'd, but the "power formulas" you see out there have me right at 400 sea level flywheel. And, I'm going down the track pushing 3900 pounds, at sea level low-13's, so put that in a lighter Camaro and imagine the possibilities.

The factory cast iron intake manifolds weren't very good. If you get a Performer or Action+, plan on gasket matching it because they build them to fit peanut heads. You can stand more cam than I've got, but don't bother with any factory valve springs if you want it to rev. My heads are the biggest oval-port, closed chambers they made. What heads do you have?

five7kid

iTrader: (14)

I refer to mine as "the baby of the family."

Rob116

So, in other words, the motor is not going into your car, is completely unrelated to thirdgens, and the answer to your question had nothing to do with which motor is better, etc. If you could answer your own question, why did you bother asking? (Read: wasting my time and consideration)

87daddyformula

Hey Rob116, you obviously haven't heard a whole lot about engines if you haven't heard of a 396 being bored to 427...infact that is about the only way you get a BBC 427; 396 and 427 share the same stroke, just a different bore.

A very wise person once said that it is better to be thought a fool, than to open your mouth and remove all doubt.

Rob116

The question that I had was this: can you take a stock 396 and bore it to 427 without damaging the block? I'm aware of the fact that a 427 is a bored 396, from the factory but that doesn't necessarily mean that the above is possible. If so, fair enough, and that's why I didn't condemn anybody for making the claim; rather, I stated that I had my doubts but would like to hear more evidence. As I'm sure you know, to take that much material out of the majority of blocks would render them utterly useless.

If it's possible, cool, I didn't know that, but I don't think that at any point did I put my foot in my mouth.

five7kid

iTrader: (14)

Maybe I buried the answer too deeply in all the other stuff I said.

'65-'66 396 and 2-bolt 427 shared the same casting. Therefore, a 427 was truly a bored-out 396 (and you can safely bore-out one of those 396's to a 427).

After that, the 396's and 402's had a unique casting that had thinner as-cast cylinder walls. Those cannot be bored safely to the 4.250" of the 427.

jms

iTrader: (1)

With little or no core shift, even the later 396/402 blocks will bore to 4.250. Been there, done that. Look for the "K" blocks.

It has been my experience that even at 4.250 bore, the 396/402 will have more "meat" left in the walls than a non-bored 350 block.

But, if you have any doubt, to make sure, it should be sonic checked.

An easy check (but not "scientific" by any means) is to look in the water passages next to the end cylinders and "eyeball" the thickness of the cylinder walls. Don't be surprised to find your block has walls from 3/8" (.375) to 1/2" thick.

And remember, an overbore only takes off 1/2 on each side.

If I was a betting man (not that racing and performance vehicles in general for over 30 years knocks me out of that category), I would say your block would most likely go to 4.250.

If not, just take it out .100 over and tell everyone it is still a 396.

jms

blue86iroc

iTrader: (2)

Take it easy, Rob116. Not all questions are application-oriented and intended to solve a problem. Sometimes, knowledge is sought just for the sake of curiousity.

five7kid, the casting number on the heads appears to be 3954281 -- but I can't find record of that anywhere. They are oval-port heads with "HI-PERF" stamped on them. Come to think of it, "HI-PERF" is stamped everywhere on this engine, including the block. The block casting number is 3969854, which signifies a 396 of 1969 vintage.

Vader

...And I thought that the 366T was the "baby" or the Mk IVs. I used to be involved with a few of those, and SSC is right. They all eat cams and lifters. Regardless of what displacement you decide to build, a roller lifter setup would probably be money well spent if you desire any longevity.

five7kid

iTrader: (14)

The 366T was the afterbirth...

I haven't had any cam/lifter problems with mine. What am I doing wrong????

The block could also be 70-72 402. Heads are a mystery, though. Are you completely sure about the number? Did you check both sides?

As far as the cylinder wall casting thickness, I suppose I should have said "without worrying". Sure, you can alway sonic check a block to see what it's good for. A '69 is bound to be pretty thin, though.

Since the engine isn't a '67 block, there's no real collector value to keeping it a 396 - the purists will know right off the bat. Once that cat's out of the bag, a BBC sitting where a BBC first lived is about all the coolness left. I've had a few surprised looks when I tell people it's just a 396, not a 454 - but even more disappointed looks when they see it's a BBC, and that's all the quicker it goes.

But, hey, it's your car, do what you want to do. I sure have. A 400-hp 396 on the street will get some attention.

Rob116

Fair enough, my apologies.

blue86iroc

iTrader: (2)

My mistake on the heads... the casting number actually appears to be 3964291, which are 1969-70 396, 402, 427, and 454 heads. Interestingly, they're labeled as rectangular port heads... but they sure look like oval ports. I attached a picture of the motor for comparison. Now, were those heads used on the 396/325 engine or the 396/375 version?

Yeah, I know about the lack of value since the motor won't match numbers -- but then again, this car has a different rear-end and suspension due its former drag days. From a collector's standpoint, it's practically worthless. If anything, the car has more sentimental value than monetary value. I just want the little "SS-396" emblems on the side to match up to the motor. Right now, there's a 350 in there... when my dad got out of drag racing he sold the aftermarket ZL-1 setup and installed a small block.

blue86iroc

iTrader: (2)

Here's the motor. I forgot to attach it in the other message.

Ian_F

454 block + 396 crank = 427. Its that simple. great engine. Big bore, short stroke. Its kinda like a big block 327.

8Mike9

Gotta see the intake ports...don't know if the exhaust ports are different or not.

87daddyformula

(Interestingly, they're labeled as rectangular port heads... but they sure look like oval ports.)

If you are using them for street use you won't want rectangular ports...Rectangular ports are more powerful yes, but at an unusable RPM range as far as street driving is concerned. They are designed specifially for racing...oval ports would produce less overall power but more power lower in the RPM range, where you need it.

(when my dad got out of drag racing he sold the aftermarket ZL-1 setup and installed a small block.)

GOOD *** MAN WHY?!!!!!!!!!!!!

blue86iroc

iTrader: (2)

I'll have to check out the intake ports tomorrow.

That's what I said! Actually, the car was such a strong runner that people were willing to buy the whole thing outright in the late 1970s... not wanting to sell the car, but wanting some extra cash, he sold the drivetrain. The car wasn't streetable at all with the 427.

This thread is already off-topic since it doesn't pertain directly to Third-Gens, so here's a picture of the Camaro in drag trim. This picture was taken before the ZL-1 installation (the 427 had a tunnel-ram setup).

five7kid

iTrader: (14)

A lot of people have dreams of a BBC in their 3rd gen. The info being passed on is relevent in that respect (I stretched the rules last spring with my porting posts).

Something tells me that engine has been racing. Magnum roller-tip rockers for instance. Deep oil pan. Nasty looking oil leaks, though.

When you first posted the casting #'s, I wondered if that's what they really were. Definately the 375 horse version. Terrible on the street. You'd be better off with oval ports, for sure.

blue86iroc

iTrader: (2)

Good thought. This is an interesting discussion and I'd like it to continue.

Quote:

Something tells me that engine has been racing. Magnum roller-tip rockers for instance. Deep oil pan. Nasty looking oil leaks, though.

That's very possible. The bearings were shot to hell, the lifters are worn, and the engine just looks like it was run hard. Cylinders 2 and 6 contained a little oil, but that could be due to cracked valve stem seals or something. Not sure about the outside leakage at this point... bad gasket, maybe. I also noticed excessive carbon buildup on pistons 2, 3, 6, and 7.

Quote:

When you first posted the casting #'s, I wondered if that's what they really were. Definately the 375 horse version. Terrible on the street. You'd be better off with oval ports, for sure.

Yeah, the intake ports are definitely rectangular. I guess I'll just have to deal with the lack of low-end power, or build up that area a little bit. The engine is completely disassembled right now, so I have a lot of freedom from an assembly standpoint.

Another interesting thing I noticed... you know that the rod caps are usually stamped with their location (i.e. a "7" means it goes in cylinder 7)? Would-be rods 7 and 8 are stamped as 5 and 6, respectively. There are two "5" rods and two "6" rods. I don't think that matters, but it's odd nonetheless.

Here are some additional pictures of the motor.

87daddyformula

I see that you also have the Hi-performance heads on there...man, all that thing needs is some TLC, some good reconditioning and a solid car and you are looking at some serious HP:hail: :hail: :hail:

I am so jelous...

SweetS10v8

My thoughts exactly!!! I was scrolling down to post the same thing!!! 427 is a great motor!

mw66nova

iTrader: (13)

buddy of mine has a 79 camaro (3500lbs?) in almost street trim with a 427 running 8.80's on a 315 bfg drag radial tire and stock style suspension. those motors are HOSS!!! of course he is spraying the bajesus out of it. regardless, it is bad. you could tag it and drive it tomorrow. (that is, if you live in GA!)

Ian_F

The 427 was the most powerful big block GM made. I would love to have one, but cash is a little tight at the moment. Maybe in a few years.

8Mike9

Grim Reaper

Nah, the LS-7 454 would be the winner for the most powerful engine INSTALLED in a production car and new 572 BB will be the outright winner as the most powerful engine offered to the general public from GM.

No subsitute for cubic inches.

jms

iTrader: (1)

Glenn, the LS-7 never made it into a factory production vehicle in 1970.

Plenty of parts for over the counter, though.

The LS-6 is still the king of PRODUCTION INSTALLED FACTORY HORSEPOWER RATED bb Chevys (although the early '66 Hi-Perf 427 vettes were rated 450 hp before the factory revised the number to 425 hp).

However, it is my belief the aluminum-headed L-88 (the ZL-1 was a L-88 with an aluminum block) probably made more "true" all-out horsepower, as installed, mainly due to the low-rise intake forced on all LS-6s in order to fit them under the hoods of the 'Vettes and Chevelles.

In addition, the L-88/ZL-1s used a more radical cam than the LS-6s.

I kind of look at it like this---The LS-6s were great street motors built-up for more (read race) performance, while the L-88s/Zl-1s were great race motors *slightly* detuned for the street (timing and stock exhaust manifolds).

I've run several aluminum-headed big-blocks (427s and 454s) street and track. If I had to choose, for the street, I would take the 454 versions.

However, I wouldn't turn down any FREE L-88 or ZL-1. Any offers?

jms

8Mike9

Bottom line is more cubes, more power.