The Stovebolt Site Forums The Shop Area The HiPo Shop Rebuilding my '63 327

I started a thread last week about a knock in my '67 327 in the engine forum. After inspection, it was determined to be a rod bearing issue with the number 8 rod bearing. It spun and both halves nested on the rod side of the crank. The number 7 rod bearing was missing a chunk of material as well, but had stayed where it belonged. This left some marks on the crank, but it looks to be rebuildable (see photos)

Now, by the numbers (V05I8KM), this was an L30 spec (275hp) engine.
Code Year CID HP BBL Appl
KM 1967 327 275 4 a/t, A.I.R.

Well, that's what it started life as. When I took it apart, I found +.030 flat top pistons and a Viking 100H cam. Crank main and rod bearing do not show any +\- numbers, so I am assuming they are standard, but the rod journals will need to be ground due to current damage.

I have the double hump heads (3890462) and cast iron 4 bbl intake (3895898 or 3895893, I'm not sure), RamHorn manifolds and dual exhaust through Magnaflow mufflers that exit in front of the rear tires.

What I would like to do with this engine is build it up to the L79 spec. (327/350hp)

I know that the block is a 2 bolt main, but I don't think any of the small journal 327 were 4 bolt mains. Does this sound like a good decision for this block? Should I go to the L79 spec, complete with dome pistons to up the compression to the factory rating of 11:1, build using flat top pistons and keep the lower compression (L30 was rated at 10:1), or do the regular rebuild using the full L30 spec? It will be going back into my '62 C10 Shortbed Stepside. I have the SM420 4 speed and a non-posi 3.90:1 rear end. I am using a Holley Mdl 4175 650cfm spreadbore for the carb.

I don't know what the difference is between the factory cam for the L30 and the Viking 100H cam, but I did like the power it produced. I would prefer to go to the full L79 treatment, but am concerned about running pump gas in it. I was currently using 87 octane regular unleaded with no pings or pre-detonation. The current +.030 have L2165 on the deck along with the 030. This leads me to think they are TRW forged pistons and correct for 10:1 CR with the 64cc heads. Would the L79 cam (3863151) or any of the current cams with a similar grind (Elgin E903H, CompCams CCA-CL12-106-3, etc..) really help at 10:1, or is the compression too low to add any benefit?

Going to the domed pistons with the 64 CC heads will put you into "racing gas only" territory- - - -100+ octane or so. Even 10:1 is pushing the envelope unless you're running a fairly radical cam. Here's something wannabe engine builders don't realize- - - -the ONLY reason to use high compression pistons is to compensate for a very long duration camshaft. That 11:1 piston needs a 300+ degree duration cam to work right, and you'll have virtually no usable torque below 3K RPM. The actual compression PRESSURE (not ratio) only needs to be at, or slightly above the pressure developed in a stock engine with a short duration cam, but since the intake valve is closing WAY up the compression stroke with a radical-grind cam, the remaining cylinder volume must get squeezed tighter just to get back to where it used to be when the engine was in stock trim. In the process of gaining some top end horsepower at speeds the average street engine never sees, you're losing massive amounts of low end torque. Why in the world would anyone want to pair up an engine that gets its usable horsepower somewhere around 5K RPM with a SM-420 transmission?

I'd suggest using flat top hypereutectic pistons with the 64CC camel-hump heads, and a Comp Cams 268H hydraulic cam that still has good low-end torque, runs well on pump premium or maybe mid-grade gas, and will wind to 7K+ RPM before it starts running out of breath. Be very sure to install screw-in rocker studs and guide plates and do a good 3-angle valve job with some pocket porting to free up the high RPM breathing capabilities. One of my students built an engine like that which turned out 400+ HP at 6500 RPM on the dyno, corrected for temperature and humidity- - - -real numbers, not a bench-racer's pipe dream. He put it in a Chevy Monte Carlo, and routinely ate 5.0 liter Mustangs for lunch at every stoplight.
Jerry

Thanks HRL! I'm not trying to build a race truck, just one with a little more get up and go than it had before this engine went south. I don't want to get rid of the 327 because EVERYONE has a 350 these days. I like having something different.

I was afraid the 11:1 was unreasonable, that's why I was asking specific questions and disclosing what I have and what my usage was. As usual, your insight and experience is greatly appreciated.

My "something different" is in the process of getting all its parts gathered up and machined so they'll work well together. It's going to have a 305 Chevy block, a destroked 283 crankshaft, NASCAR specification tool steel connecting rods, and a roller cam with a rev kit. It will be slightly over 250 cubic inches, and should live quite happily at 8K+ RPM. It's going to be installed in a home-built tube steel frame with an Excalibur Roadster fiberglass body. The whole vehicle will probably weigh less than 2500 pounds. That engine should sound like a bumblebee on steroids when I get it wound up tight!
Jerry

Sounds like a lot of fun! Where do you plan to run something like that?

I'm going in the opposite direction with my build. I'm returning my '62 C10 to near stock levels, or at least the appearance of stock. I've even gone as far as to remove the plugs in the Oil Fill Tube and Road Draft Tube holes that are plugged on a '67 engine and installed the Oil Fill tube with breather cap and I'm currently fabricating a new plug for the road draft hole that will accept a PCV valve so I can put the old Chevrolet script valve covers on it. Make the '67 327 look like an old '62 283.

However, I love the extra umpf that the 327 has over the old 283 (rated 145hp) that I use to run in my '63 C10. So, I will look at the specs on the cams you mentioned and see what I can see. I don't mind doing research and changing direction when I've gone off track. My 462 heads are fairly stock. I don't think anything has been done to them at all, so 7k rpm is out of the question for me at this point. I think that 5K is about the limit I will ever be pushing with my set up. Besides, I'm on a tight budget on this build, so wild is definitely out of the question.

I'm thinking that more grunt off the line is good. As it was with the 327 and the SM420 and 3.90:1, I could smoke 1st, burn 2nd, and get a decent scratch going into 3rd. 4th was too tall to doing anything except go forward. It was rare that I would do that, but it was nice knowing that the power was there when I needed it. Usually just used it in a nice, sedate putt-putt mode, but if I needed to get up to speed in a hurry, I could do it. There is no speed shifting an SM420. It was a nice reliable 65-70 mph on the freeway kind of set up, but could do short bursts of 75-80 if needed. I just didn't like to run it for long at those speeds. Besides, the stock suspension on a '62 is not set up for high speed.

I'm getting sort of sneaky with the Excalibur- - - -the bellhousing bolt pattern is the same for several engines- - - -the Mercruiser Marine 4 cylinder, the 4.3 liter V6, the 230/250/292 inline sixes, and all the small block and big block Chevy V8's. With a little tinkering with motor mount locations and exhaust pipes on any particular day, I could run any of those engines. When the car that pulls up beside you at a stoplight can have that many powerplant options, would you challenge him to a friendly street race?
Jerry

Not a chance!!

My old '63 C10 was a sleeper like that. I had 2 different configurations that I liked very well. The '65 corvette 327 with the '57 corvette dual quad high rise with dual Carter WCFBs. Paired with a TH400 and 3.73:1, that baby screamed, but like you noted before, no one really needs that kind of rpms in a truck. I made it to 135mph with that setup, but swore I would never, ever, do it again!!! Too fast for that chassis. The other was a small block 400 with the Holley 4165 650cfm spreadbore, the TH400, and the 3.73:1. More grunt, less top end. Topped out around 105mph or so, but got there really quick.

I don't know why I was even thinking about trying to revisit the high rpm monster 327 again. My '62 doesn't have any better suspension than the '63 did, and the aerodynamics are just as bad, if not worse. That was the big problem with the '63. As the speed increased, so did the airflow under the truck. It created an airfoil that lifted instead of squatted. High speed = high on the suspension and absolutely no room for error.

I think your Excalibur will have a lot better aerodynamics.

One more bit of trivia- - - -the Excalibur frame is also being measured and tweaked for a Jaguar independent rear suspension with a sprung-weight third member and inboard disc brakes- - - -should make it handle like a "rocket sled on rails"!

An old geezer WWII vet from my home town was one of the first hotrodders in our area to experiment with nitrous oxide back in the late 1960's. He had a ratty-looking old 57 Dodge pickup with a 440 in it and a nitrous bottle under the hood. When he hit the loud switch the whole back end of the truck disappeared in a cloud of tire smoke! Later he built up a 49 Chevy coupe with a highly-modified 327 and a Muncie 4 speed with a Hone overdrive that worked on 3rd. and 4th. gear and a 3.08 rear end. His top end was somewhere in the 150+ MPH range.
Jerry

Dang! You get all the new toys.

I can't wait to start seeing pictures of this thing.

I'm going to be taking the block, crank, rods, and pistons to the machine shop today to get the process started. I looked into that Comp Cams 268H hydraulic cam you mentioned above. I noticed it has .477 lift, requires different springs and head machining for the new springs. XE268H That's something I can't do with this build. Too tight of a budget.

Any suggestions for a different, less lift cam I can bolt in with stock components?

Actually, a set of standard-diameter Comp .500 lift springs or an equivalent spring that doesn't include the ridiculous Comp brand name price markup drops right in, and works well with that cam up to 6K+ RPM- - - -no need for special head machining. There's also a taper-wound "beehive" spring available that has a smaller diameter at the bottom and fits the original spring seat. You might have to shorten the tops of the valve guides a little to make sure the spring retainer doesn't get too close and mash the umbrella-style valve stem seals that work better than the OEM O-ring seals that fit underneath the split locks. If you use the umbrella seals, DON'T use the sheet metal caps on top of the springs or the O rings- - - -it's possible to seal the guides too much and wear them out. Eliminating the sheet metal caps also gives you a few thousandths more of lift capability before the springs try to stack solid. I use a piece of paper clip wire and a temporary solid lifter during assembly to check for coil bind- - - -if the spring coils pinch the wire, you're too close to a solid stack and need to machine the spring seat a little deeper.

Edit: There are several spring sets on Ebay that will accommodate a .500" valve lift, ranging in price form the mid-30's to just over a C-note. The springs that require head modifications are larger in diameter and will accommodate a second spring for sustained high-RPM operation like on a high-banked round track where the engine stays in the high RPM ranges most of the time. For the occasional tire-smoking session on the street, those springs aren't really necessary.
Jerry

Thanks Jerry.

That makes me feel a bit better about that cam.

I took the block, crank, rods and pistons to the machine shop today. Apparently, the stamped numbers I was looking at on the bearings we're not the numbers I was looking for. Both the rod and crank bearings measured out at +.010, so I'm looking at a 10/10 crank at the moment, but the machinist there said it looks like he can clean it up at 20/20. He said I shouldn't have any trouble with it at that level.

We'll see what we see, when we see it. :-)

See if he can also "index" the crank as he's regrinding it. That puts the throws exactly 90 degrees apart. We used to do that on round track cranks, even if it meant a good standard-diameter crank had to have the rod journals ground 10 under to get the indexing right. If your main bearing journals aren't worn out of round or scored, there's really nothing wrong with just polishing them instead of regrinding. That would give you a 10/20 shaft with just a bit of extra oil clearance on the main bearings.
Jerry

Jerry,

I found these springs on Summit. It looks like these will fit the stock heads and still handle a .500 lift. What do you think?

Howard Valve Springs

$32 for a set of 16, 1.250 diameter, and the FAQ says it will handle .500 lift.

That's a good choice for your application, but don't necessarily buy into the claim that you need those expensive retainers to go with them. Buy the springs first, and check your stock retainers to see if they work with the springs. You definitely don't need the 10 degree retainers for street use!

Thanks. You just answered my next question as well.

I do appreciate all the help. It's been more than 30 years since I built my last sbc, and back then, it was basically a stock rebuild. No fancy cam and spring options to consider. I have no problems with the actual mechanics of tear down, clean up, and reassembly. It's the choosing the correct non-stock parts to combine to get the motor that will fit my application that stumps me. I just don't have the experience.

Ordered the cam, lifters and springs today. Still waiting to hear back from the machine shop on what size bearings I need and if I can get away with just a cylinder hone and new rings or if I have to bore to the next size up. Hopefully I can reuse the forged pistons I already have. Once I have that info, I will order the master kit.

Do your heads still have the pressed-in rocker arm studs? If so, it would be wise to cross-pin them by drilling 1/8" holes slightly off-center in the stud bosses so they nick the side of the studs about half the diameter of the drill bit, and drive 1/8" roll pins into the holes to keep the studs from pulling out of the heads. That's how we secured the studs in the days before screw-in studs were available. Now I machine the stud bosses down about 1/2" and install heavy duty screw in studs and pushrod guide plates.
Jerry

Good News/Not so good news.

Heard back from the machine shop.
Bore is still really good, as I thought. A simple honing will clean it up. Since the bore is staying at +.030, I can continue to use my current TRW forged pistons, just add new rings.
Main journals needed to be ground down from -.010 to -.020.
Rod journals were in fairly good shape, except for the 7/8 journal where the bearing spun. They will need to go from the current -0.10 to -0.30.
New valve springs came in a couple of days ago. They were able to go on with no problems.
New push rods came in a couple of days ago, and the new cam and lifters came in this morning.
Master kit is due in tomorrow according to the shipper, so I can get the new cam bearings to the machine shop and have them installed soon.

I also decided that while I have the engine out, I am going to replace the clutch, the pressure plate, the throw out bearing, and pilot bushing. Preventative maintenance never hurts.
Those should be in tomorrow as well.

I'm happy to see this project coming together. Maybe I'll have it running for New Years Day! Depends on how soon the machine shop has the block and crank ready.

A 20/30 crank isn't bad, but that will probably be the last time it can be reground. Does your engine have the large or small journal size? Early 327 engines and the first year of the 302 (Z-28) Camaro engines had 2.000" connecting rod bearings. Later ones have the same size rods as a 350, 2.100" diameter. The main bearings are also larger on the later engines, but I don't remember those dimensions off the top of my head. Small-journal 327 cranks are just a little hard to find these days.
Jerry

Small journal. '67 was the last year for them. I'm going to start my search for a replacement crank soon. I will be keeping this truck/engine combo for a long time.

I thought about trying to drill and tap the snout of the crank for a harmonic balancer bolt, but decided that the $42.50 the shop wants to do the job was money well spent. Otherwise, I would have to wait for the jig to arrive from Jerry, then do the work, and possibly screw it up, it happens, This way it is done and I know it's right. If it's not, they can replace the crank. It's also a lot faster since they already have the crank any way.

Clutch kit got here Saturday. I thought that the master kit was going to be in the same box, but it was 2 shipments from different locations. Master kit should be here tomorrow.

A 307 engine has the same stroke as a 327, and a damaged or badly worn "large journal" crank can become a standard-diameter small journal item if your machinist is willing to do the work. The casting number won't be right but the engine won't know the difference. Some guys don't like putting that much wear on an expensive grinding wheel, or spending the time necessary to do it.
Jerry

Jerry,

Thanks for the tip. I'll keep that in mind.

Got bad news from the machine shop today. I haven't been down to look at the block yet, I'll do that tomorrow, but I've been told the magnaflux uncovered a couple of cracks in it. One in one of the #4 Main Bearing cap bolt holes (numbering front to back), and another in the webbing.

Looks like I may be replacing the block as well. Of course, I have already bought all the parts for a small journal rebuild.

Oh well. Machine shop is checking for a replacement block. Looking online, I have seen a lot of high priced blocks, most pretty worn out. Machine shop quoted $150. If they can find a small journal 327/302 block that is +.030 or less, I'll go for it. I have compiled a list of acceptable block casting numbers to take with me as a reference before I accept just any block from them.

Of course, I will want them to mag the block before I buy it. I don't want another boat anchor.

These trucks never make it easy.

Ok- - - -there's another option. There is a set of thick wall main bearings available that will allow a small journal crankshaft to fit a large journal block- - - -even one with 4 bolt main bearings. They're similar to the bearings used to run a 350 crank in a 400 block. I don't remember the part number off the top of my head, but a quick call to my parts guy in Nashville tomorrow will refresh my memory. If you want a really unique 327, how about building one with a 4 bolt main 350 block? Those blocks are still pretty available at reasonable prices. I've got 3 or 4 of them stashed away right now. I'm thinking of building a faux Z-28 302 with that setup- - - -a 4 bolt 350 with a 283 crankshaft in it.
Jerry

That's an interesting concept that I have thought about, but I would still need to find an older block because I want to run the PCV out of the road draft tube hole, not the valve covers if possible.
That would make it a lot easier to get a block, and I may have to give up that idea if I can't find a decent block at a decent price.


I will keep it in mind.


Edit: If I do go that route, that would make a later rebuild easier to get a 327, just use the 307 crank you mentioned in an earlier post.

I've got a 4 bolt 350 block in a pretty accessible place in the storage shed. I'll do a little investigating and see if it's feasible to drill a hole back there to make it possible to have a block-mounted PCV. Most casual observers wouldn't have enough savvy to spot a modification like that, and if they did, there are a few other, more obvious differences to look for. "You can't fool all of the people all of the time!"
Jerry

Here's what I was able to snap a photo of this morning. This is on the #4 main cap (counting from the front), both sides (passenger/driver) coming out of the bolt hole and extending up into the webbing towards the top of the block. Sorry the shots are a little blurry. They looked good at full size on the phone.

My block is the first one, there is a block that is at the machine shop, but owned by a customer who has left it there for over a year that is the second number.

Casting
Number Size Year Main Bolts
3892657 327 67 2
3782870 327 62-67 2

Second block is supposed to be still at standard bore, but needs to be bored. Machine shop will be calling the customer today to see if he would be willing to sell it. We'll see what happens there.

The standard-bore block would be a good choice if you can get it without paying a king's ransom. I have run blocks with those kinds of cracks on the round track at HP numbers far above stock by brazing and using helicoils to reinforce the threads, but we didn't expect them to live very long- - - -half a season, usually, and maybe 500+ racing miles before they hand-grenaded.
Jerry

Well I finally got an answer back on the standard bore block at the machine shop. The owner is willing to let it go for $200.

It's going to be bored +.030 to match my forged pistons, get the cam bearings installed, and should be ready for me to pick up by the end of the week.

Hopefully, I can get started on my end of the project early next week. I want to get this thing back on the road.

Don't trash the cracked block- - - -it can probably be repaired by someone willing to put a little time and money into it for a numbers-matching restoration than won't be run hard. I've salvaged a block that survived a pretty massive blowup on the track- - - - -it swallowed a valve at the end or a straightaway and hydraulic-locked from about 6K RPM because the valve poked a hole in the cylinder head and flooded the engine with coolant. One sleeve, new connecting rods, pistons, camshaft and heads, and it went into a street machine. We didn't look too closely for cracks, but that engine ran for several more years.
Jerry

I hadn't planned on keeping it as I don't have a lot of room to store it. I was thinking of leaving it with the machine shop if they wanted it. That should give it a good home with a chance at a new life down the road.

I was able to bring the "new" block home today from the machine shop. 4.030" bore on a 1963 327 block. Deck was milled .008 to clean it up. Crank came in at -.020 mains and -.030 rods. The snout did get drilled and tapped for the harmonic balancer bolt. Pistons are TRW Forged +.030.

The fun starts tomorrow.

Good looking machine work! Remember that forged pistons need a bit of extra skirt clearance because they don't have a cast-in strut to retard expansion. I usually go for at least .003" or maybe a little more. They'll rattle a little when the engine is cold.
Jerry

Thanks for the reminder

Day One.

I didn't get a lot done today, but I did get the expansion plugs, crank, rods and pistons/rings installed. All torqued down and everything still spins as it is supposed to.

Not really putting a time table on this build. I want to make sure I do it right the first time on each step.

Today, I got the cam and timing gears installed as well as the oil pump. Since I had so much metal go through the engine before the rebuild, I opted to replace the oil pick up and screen assembly instead of cleaning the old one. It was a $15 insurance policy. Well worth it in my book.

After inspecting my harmonic balancer, I will be installing a sleeve on it. There is a small, but distinct groove in it from the old front seal. Another cheap insurance policy. This one is $10.00.

It's getting there.

Mostly clean up and paint today. It took 4 sessions of degreaser and scrub brush to cut through the accumulated crap on the oil pan, but it is now sporting a fresh coat of Chevy Orange engine paint, so is the timing cover. Both are now ready for installation.

Both Ramhorn manifolds were wire wheeled and sprayed with the Flameproof 1500* flat black paint. It may not be stock, but I'm good with it for now.

Entire engine will be painted in Chevy orange before installation.

Sounds good. You did pull all the oil gallery plugs and run rifle or shotgun cleaning brushes through the passages, right? I used to run oil gallery restrictor plugs in the back of the block to prevent flooding the valve covers with too much oil and keep more of it in the lower end, but I'd open up the holes in them to 3/32" instead of 1/16" when I was using anti pump up hydraulic lifters. The restrictors still allowed enough oil flow to keep the lifters filled, but they minimized the flow to the rockers and kept the drain channels from the heads back to the crankcase from getting overwhelmed with oil volume. That was particularly important on a round track where the oil return to the pan might get compromised by G forces in the turns.
Jerry

Yep! First thing I did when I got it home.

Got some good time in on the engine today. I was able to repair the balancer and I got the engine up to a long block before I quit for the day. I probably won't get anything done tomorrow. Too many non-truck plans. Should get more done on Sunday.