chevy 327

[mnwildpunk]

I wasn't sure if this went in general or here. The other day I was given the chance and bought a 327. My question is this I know except for the stroke this engine and the 350 are the same engine. I'm just wondering why 327 owners are so much more passionate then 350 owners? I have talked to a few 327 owners who think their engines are the be all and end all to all enginedom. By the numbers there is no credit to their statements but I got the engine to pop in my Camaro just to see if the hype is true. Please give me your opinion

[ChrisPflug]

Mainly the era these engines were built- 60's Chevies are "classic" while the 70's don't generate as much enthusiasm automotive wise. There were also some great factory 327 high performance packages but the lower level 327s were a far cry from the Fuelies or higher performance versions. Actual performance 350s were only offered for a few years and not as widely available as the hotter 327s either- If the 350 had ended with the original LT-1 rather than being Chevrolet's main engine of the "smog era" they would probably carry a bit more "mystique"

Used to be anyone that had a 327 always referred to their example as a "Vette motor"

Lots more 350s built but the majority of them came in very mundane packages

The 350 has quite a few construction "details" to make it more suitable for the extra cubic inches and heavier applications

[disabled modeler]

Me I am a 350ci guy one can build or do about anything with them if desired...327ci many were performance use better heads,etc.models(68 Impala 300hp 327 for instance)...they ran very well in a heavy car. Vintage 1974 350ci engines from pickups,suburbans,etc. most had 4 bolt main barring caps and bored 0.30 over sized made a 355ci which was a great power combination with a mild or large cam.

[Ace-Garageguy]

I'm just wondering why 327 owners are so much more passionate then 350 owners? I have talked to a few 327 owners who think their engines are the be all and end all to all enginedom.

The answers above pretty much cover it, and your realization that the numbers don't lie is spot on. A lot of muscle-car or vintage-car or hot-rod owners have very little knowledge of the science and physics of engines, but they have a lot of enthusiasm for somewhat misguided and incomplete popular "knowledge".

Here's a copy of the real deal from http://www.badasscars.com/index.cfm/page/ptype=product/product_id=115/category_id=13/mode=prod/prd115.htm

Is a 327 Chevy a better performance engine than a 350?

This is a big misconception. First of all, let me repeat the old saying "there's no replacement for displacement". In other words, if a basic performance engine makes say, 1 HP per cubic inch, then it's pretty obvious that a 350, with 23 more cubic inches is inherently going to make 23 more HP than it's smaller cousin, the 327. Both the 327 and 350 have 4" bores. The 327 has a small 3.250" stroke and the 350 has a longer 3.480" stroke. With that, you take into consideration engine physics, and consider that the extra 23 cubic inches of the 350 is all via the crankshaft stroke, and you automatically gain more torque on a logarithmic scale than if it were 23 cubic inches by bore size alone.

Ok then, now you're probably saying, "well, some of the 327's in the early 60's were rated at 365HP carbureted, and 375HP with the Rochester Fuel Injection system, and the 350's didn't make that much power at all“. OK, let's think about that for a minute; The 327 was a popular Corvette engine and the 350 wasn't really available until 1967, (and only in some models of cars in 67), and they didn't start getting popular until 1968. When the 350's did finally come-out in mass numbers, most were in mild cars such as Grama's big old Caprice or Dad's truck, and they didn't really start getting their "performance" reputation until the 1970 and 1971 LT-1 350's came-out in the Z/28's and Corvette's, so it "appeared" that the 327's were more powerful engines than the 350's. The bottom line here is simple, no matter what you do to a 327, if you do the same thing to a 350, it WILL make more horsepower and torque than a 327, period. The same thing goes with ANY engine when comparing cubic inches and power, especially when you are talking about making more torque with longer strokes. Could the 327 rev higher than the 350? Physically, with the shorter stroke and less reciprocating mass than a 350, in theory, YES they could, BUT because of the heads, cams and valve train limitations, in most cases, reving higher meant absolutely nothing as far as making any power up at those RPM's. See our Tech Tip titled "How high will one of your Bad Ass engines rev?" and that'll explain that subject better.

Edited July 29, 2014 by Ace-Garageguy

[Tom Geiger]

End analysis is that the 327 will be very cool in your Camaro!

[mnwildpunk]

End analysis is that the 327 will be very cool in your Camaro!

thanks guys for the answers but ol tom won the best answer award

[Tom Geiger]

thanks guys for the answers but ol tom won the best answer award

LOL.

[Ace-Garageguy]

If you're gonna put a 327 in your Camaro, you might also consider using the famous "double hump" heads. They're still available in junkyards, and they work very well. Many years ago, I put a 327 (365-horse based engine, but with headers and a little more cam) with the double humps in a Triumph Stag. Pretty fast car.

Here's a nice article on compare / contrast of the best of the 2-humps.

http://www.circletrack.com/enginetech/ctrp_0912_chevrolet_double_hump_cylinder_heads/viewall.html

[twopaws]

When I converted my 66 Nova from A/S to Modified Production, I pulled the 327/350 horse and went with a 350 block. This primarily due to the anticipated higher rev count so the 4 bolt main just made sense. At least to me.

[Harry P.]

I have a '67 Impala with a 327. Sweet engine.

[High octane]

Do you take your car to any car shows or cruise nights Harry? Do you have a blower for the induction system?

[Harry P.]

Do you take your car to any car shows or cruise nights Harry? Do you have a blower for the induction system?

No car shows. It's just my weekend toy. And mechanically it's stock. I added a modern stereo and aftermarket wheels, but as far as the engine/chassis/drivetrain, it's 100% stock... right down to the two-speed Powerglide automatic.

[Ace-Garageguy]

I added a modern stereo and aftermarket wheels...

[Harry P.]

I like to think my Impala is a bit more tasteful...

[Ace-Garageguy]

Very good looking car. Sorry about the donk thing. I just couldn't resist.

Edited July 29, 2014 by Ace-Garageguy

[High octane]

LOL! I wouldn't be able to resist either. Very nice lookin' ride Harry and it's a LOT more tasteful.

[jeffs396]

To add a bit of info here, the best 327 blocks (if you want to build a high performance engine) are the latest production ('68-'69) because they have the large journal crankshaft, like the 350. If they would have only tooled up for 4-bolt mains...

Harry, did you ever build a scale replica of your '67???

Edited July 30, 2014 by jeffs396

[Harry P.]

Harry, did you ever build a scale replica of your '67???

No. But I should!

[Ace-Garageguy]

To add a bit of info here, the best 327 blocks (if you want to build a high performance engine) are the latest production ('68-'69) because they have the large journal crankshaft, like the 350. If they would have only tooled up for 4-bolt mains...

So can you run a large-journal 327 crank in a 350, 4-bolt-main block ? That should give you a 4-bolt 327. They both have 4" bores, the bore spacing is the same, and the heads will all bolt on.

Will the crank work ?

[jeffs396]

Yes Sir!

http://www.small-block-chevy.com/SBC_crank.htm

The factory built crankshafts

Stock strokes offered by Chevrolet go like this. The 265 and 283 carry 3-inch strokes, both with the smaller diameter journals. The 327 has a stroke of 3.25 inches and is available in both small- and large-journal versions. The 302 crank goes goes back to the 3-inch stroke, but unlike the 265 and 283 crank, the 302 spins on large-diameter journals. The exception to this is the 1967 302 which had the small diameter journals. The 350 crank has a stroke of 3.484 inches - also with large diameter main and rod journals. The 3.750-inch stroke 400-inch crank is unlike any of the other cranks listed for the small block, it's cast, while many other cranks are forged. Rod journals are common with those of the late 327, 350 and 302, but 400's main journals are a one-off size for the small block at 2.65 inches. The bore of the 400-incher is 4.125 inches. One of the most popular of all combinations used to be the 327-crank-in-the-283-block trick. This can be done without machine work, but you'll need the early (small diameter) crank. There is a fly in the ointment though, and you should be aware of it before laying out cash for parts. Not all 283 blocks will accept an early 327 crank due to the counterweights on the crank contacting parts of the block. Two things you should not do is turn the counterweights off the crank or grind on the block until clearance is gained. The amount of material needed to be removed from the block is a bunch in at least one area and you are sure to hit water. Turning down the 327 counterweights will create a very bad imbalance situation so just keep trading or shopping until you come up with the right 283 block as described earlier . This 3.25-inch stroke by 3.875inch bore engine yields 307 CID when used with stock rods - which have to be the small-bolt, early rods. Don't confuse this home-grown mutation with the Chevy-built 307 which has a large-diameter cast crank and rods with the 3/8-inch bolts. The drawback to the Chevy-built 307 is its very-low-compression cast pistons. In the piston department (for the home-built 307) you have a choice of high-performance slugs, the 307 stock pistons or some of the TRW forged pistons which are the budget racer's dream come true. You can't use 283 pistons - they're the right bore but the wrong compression height. Because the late 327 block is also used for the 350 CID engine, a 350 crank can be laid in the 327 block. The stock parts combination gets out of hand in a hurry and so does the endless variety of stroke combinations which can be obtained by turning the project over to a crank grinder. On engines to be built on the basis of a 265, 283 or early 327 block, a large-diameter crank can have its rod journals reground on an offset to produce a non-welded stroker. The maximum stroke to be achieved by this method is 3-9/16 inch on a 350 crank. By welding up the journals and then turning,them down, most any stroke you can dream up.

One of the more popular combinations today is the 383, having a 400 crank ground to fit a 350 block. With a 3.75" stroke, a more perferrable rod to stroke ratio is achived and this combination produces excellent low and mid range torque. Another hot item is the 377, a 400 block with a 350 crank using special spacer beraings. Both of these combinations require special pistions to achive the required compression height. However, with the popularity of these engine combinations, the required components have become a "shelf" item at most speed shops and mail order performance outlets. We are working on an area of this site which will address the 383 and the 377 build up. As these pages are complete a link will be added here.

back to SBC main page

[Old Nasty]

Where are the wands for spraying crops?

[Ace-Garageguy]

Thanks for the crank info Jeff. Great to find guys who know their 1:1 stuff, and where to go to look it up.

[mnwildpunk]

Well I got my 327 on the engine stand and I pulled the pan and heads in looks good and healthy with no surprises. I'm planning on freshing things up and in the camaro it will go

[unclescott58]

My one thing to add. Actually two. The 350 was only available in the Camaro 350-SS early in 1967. The engine was introduced with the Camaro. And the LT-1 went beyond 1970 and '71. It was still the standard engine in '72 Camaro Z-28s, and optional in '72 Vettes.

Scott

Edited August 2, 2014 by unclescott58

[Greg Myers]

327/350 ? 400 "If'n some is good, an' More is Better, than TOO MUCH must be just right."