Easy Rhino

I'm soliciting your inputs on what pieces parts to use in my 1965 Corvette engine.

(aka: spend my money)

Boundary conditions (I know crate engines, aluminum heads are cheaper/better):

- Originally built as a L76, I want to go back to that kind of a build.

- 327 small journal block original 4.000 bore, 461 double hump heads.

- Original cast iron manifolds, Winters aluminum SHP intake, correct Holley carb, and correct dizzy. Will exhaust through original 2 1/2 inch rear exhaust.

- Has no power accessories, and intend to run the original 6 quart pan, and the original accessory drive system: 8" pulley, idler/tensioner pulley etc.

- Will be used with original M21 4-speed and original 4.11 rear gears. Mostly used as a short run cruiser, with an occasional long day of back road cruising.

What I'm specifically asking for from the wise and all-knowing forum:

- Your opinions/experience on a well-matched set of rods, pistons, cam, and valve train. Obviously, compression ratio comes into the discussion, as does the argument on 2.02 vs 1.94 inch valves, and entire valve trains.

- I like a lumpy cam sound, don't care a lot about manifold vacuum (should I?), don't mind adjusting solid lifter cam lash on occasion (but probably don't drive enough to need it very often) and don't have any difficulties with use of a clutch.

- I currently have a C6, so I don't need my '65 to outrun anything, just to be fun to cruise around in.

Have at it (please don't get your feelings hurt if I - or others - don't go with your choices verbatim).

Kevin

Bluestripe67

You want to read SWC Duke's papers on engine build. Search! Dennis

warrenmj

Ah, that's no fun

Scott Marzahl

Stock L76 Federal Mogul pistons, Crower Sportsman rods, replacement LT1 cam.
Have the stock 2.02 heads ported. Send carb and distributor to Lars for rebuild/rework,

atlastc6

Built mine last year to OEM specs with help from guys here. Turned out fantastic, forged pistons 11-1 compression 30-30'cam OEM specs. Runs fantastic on pump,gas revs like a L76 should. My .02.

Critter1

If the cylinders need to be refinished, use ONLY an automatic feed precision hone. No "by hand" cylinder honing will do. Don't let the rebuilder talk you into align boring the main bearing bores. Also, be very specific when you give the block to a machine shop about NOT decking the block. I would use the correct original 30-30 cam. No point in doing any port work on the heads, at all.
Engine rebuilders will typically try to talk you into all sorts of non essential processes.

vetsvette2002

Good advice Cranky
one other tip: DO NOT ADD HARDENED SEATS FOR THE VALVES

427Hotrod

I'd build it with aftermarket rods and find the absolute lightest pistons available. Not std replacements. Since no decking...I'd have them made .020" or so taller (or whatever it takes after measuring block) to get near zero deck height. Even if they are a little above the deck, you can compensate with gasket to end up at less than .040" total.

The heads would have the 2.02's and I'd definitely port them. I'd install good guides (no hardened seats) along with good valve stem seals. I'd have someone who knew what they were doing to do a real valvejob with an aim towards the flow. The intakes would get a 30* backcut on the valves.

I'd use a Crower #350 cam. It's a great little solid flat tappet that just flat works in these type motors with stock type heads. Sound incredible, won't hurt parts and will rev to the moon. Also drives great and with 4.11's you'll really love it.

I'd port the intake and exhaust manifolds.

Tons of other little things...but that's a solid basic combo that will run killer while looking stock.

Now of course dropping in a stroker crank would be great too. It can be done with small mains.

JIM

cardo0

Well usually the dynamic compression ratio determines how much cam seat to seat cam duration you can use. Really the fault lies with the owner that is to lazy to make an accurate volume measurement of both above the piston and the head chamber. Published stock values for volumes is very inaccurate.

With a short stroke 327 piston speed will be slow enough for hypereutectic pistons which seal better than forged and are usually lighter/cheaper.

For a 327 stock rods are plenty strong. Polish the beams, shot peen, and install ARP rod bolts and u will have much more self satisfaction using them than cheapo aftermarket rods. But have them magnifluxed/inspected before you start to work them.

Heads? Big 2.02" valves and unshrourded chambers are a big help. Pocket porting by someone that understands the throat taper rather than just hog it out will help more to.

So when you get the compression volumes measured let us know so we can help you choose a cam.

Hope this helps.

wmf62

no way...

Robert61

If this is open to all opinions I'll chime in. Stock crank is fine get a good regrind, bored, honed with a torque plate, if you want it decked there are now machines that can deck it and leave the stamping so in place and no one would ever know it's been decked, not necessary in my opinion. A set of Scat h beam rods, floating pins if your pistons allow. Forged flat top pistons. Definately balanced. Cam 230* int 240* ex 106* lobe separation if you want it to cut up 110* seperation if you want it more mild mannered, .500" lift. Since you're staying with 461s, brass guides, screw in studs, 2.02 intake valves with pocket porting. I will differ from 2 already posting and I guess there is a CF consensus that somehow they are unneeded I would not even begin to do a new build without hardened seats. I would stay away from 1.600 ex as you're more likely to crack the heads putting over size seats in as well as the possibility of cutting through with bigger seats. Moly rings, Fel Pro gaskets, a pink spring in a stock volume oil pump, steel sleeve on the oil pump drive, good push rods and you should have a pretty good piece.

Easy Rhino

Ask and ye shall receive! All helpful inputs guys, thanks.

I'm on it - since I'm home on the puny list today (flu bug?)

Sounds solid - but no 30-30 cam?

That's the dream right there.

Thanks for that heads up. Since my block looks so good, not even a ridge at the top, I was going to just dingleberry hone it. Bad Idea? No?

Wow, that's a lot to chew on, but I like what you're laying out. Do hypereutectic pistons satisfy your criteria? I'm reading that rods are critical to keeping an undamaged block at high rpm use, but that most major (non-chines) sportsman type rods will be strong enough?

I hadn't even considered a stroker - now my head's spinning.

Yes, all of this helps, thanks.I'm way OCD enough to take detailed measurements to determine actual CR, so should I wait on the cam until the rest of the engine is known? I still have rods to work through - I don't want to risk my block with crappy rods, or old defective Chevy ones, so I gotta study this more.

Of course, and the more the merrier. Interesting that your pick is the flat-top pistons, I was thinking hyper-eutectic high CR ones. Lots of good detail in your build, including some of the finer points, thanks.

Thanks, Guys, and keep 'em coming!

65tripleblack

Do you enjoy doing things yourself? If so you'll get a big boost in power if you port the heads. Pick up Vizard's book and have some fun. DO NOT HAVE HARDENED SEATS INSTALLED. My 327 made 380 RWHP after I ported the 461 2.02/1.6 heads. The intake ports on those can be opened up to 185 ccs. Despite what you've heard, there is some work that you can do to the chambers to increase flow. 427 Hotrod has some good ideas, and it is VERY important to minimize quench which will improve detonation resistance and allow faster spark advance.

IF YOU ARE SET ON USING THE 461 INTAKE AND IRON MANIFOLDS then I'd suggest you use the 151, 962 or 178 cam with stock type pistons. Do you want a roller cam? A roller will lift the valves faster than a flat tappet cam which means a flatter torque curve which extends further in both directions. Big power gain but requires other expensive head mods, plus the high price of the cam, lifters and rockers.

If you intend to wind your engine higher than around 6500 RPM, then I took Duke's advice and bought Crower Sportsman small journal rods on a group purchase some years ago right here on this forum. These roods are expensive, and nowadays I believe that Scat rods are recommended.

I use the stock SHP crank, but have done lots of improvements to it. I also use the Sealed Power stock replacement pistons L2166NF, but they are heavy and use old fashioned wide groove rings. There are much better pistons out there using low friction narrow rings, but the FM's are cheap and good enough.

Sky's the limit but how fat is your wallet. As an example, I get close to 500 horsepower and a very flat and broad torque curve out of 331 cubes. I take mine to 7500 routinely where makes about 90% of peak power which occurs at 6400 RPM.

The cheapest and easiest way to get more power is to stroke it.

TexVette66

Z28 type oil pump

Critter1

I think you're getting a lot of bad information here.

In your original post, you indicated that making a lot of HP wasn't your goal.

Much of the info posted is way past your goal, or just a waste of time and money.

A L76 is a nice engine just the way it is. It's not going to be as fast as your new Corvette even if you spend a lot of money on it.

What's wrong, if anything, with the engine now? Does it really need overhaul?

Robert61

Of course, and the more the merrier. Interesting that your pick is the flat-top pistons, I was thinking hyper-eutectic high CR ones. Lots of good detail in your build, including some of the finer points

That was nothing but 350 on the brain. Yes I would go with domes and around 11:1. Have you measured the cylinders? A few months back I was working on a 396 for a friend. It was running fine. They pulled it out for a rear main leak. Then he says while you're at it change the cam. One thing leads to another and the heads are off. I'm looking at the cylinders and thinking wow there's no ridge in the cylinders. I started checking them and the first side is not great but I would have gone back with it then I got to the other side and one and .010" taper. Someone had ridge reamed it.

karkrafter

If the bores are good enough to bumblebee hone [which is rare] what could possibly be wrong with the pistons?

cardo0

I've had at least 4 sbc over the past 40 yrs and never had a rod failure. My first 327 in high school took a heck of a beating and never quite. Unless you're running nitrous or circuit track racing at 6,000 or 7,000 RPM for an hour at a time i think aftermarket rods are not needed. I even had a Pontiac GTO with cast iron rods that never broke either. And if you're using the stock crank all you need is to match piston weights then for balance. Where did you read stock rods are crappy rods? Magnaflux/inspect, polish the beams, shot peen, install good bolts and resize/recondition and you now have rods you know are good with some self satisfaction too.

You mention a ball hone well that is mainly for a re-ring and bearing overhaul as the ball hone only breaks the glaze for new rings to seat - removes no metal. You have to measure the block bores and tapers to see if you can do this or if you need a rebore. Nothing wrong with boring the block all the way to 0.080" as you can still find pistons on the shelf for this and it adds cubic inches. If boring the block then having zero decked is a good idea which allows a good thick head gasket and good quench.

Are hypereutectic pistons good enough??? Just look at the GMPP catalogue and all the sbc crate engines including the ZZ435 and circle track engines all use hypereutectic pistons. Most the LS performance crate motors use them to. The real question is can you find one with the right size dish and weight. For a 327 you may even need a shallow dome.

Yes choose the camshaft last. You can find a cam to fit your compression and combo much easier than buy pistons and head chambers to match the camshaft - make sense?

427Hotrod

Hyper's are OK for many people...but I won't use them. There's a HUGE difference in a Mahle hyper that Porsche or a high end GM uses and what is generally sold in the aftermarket. Plus late model stuff has computer controls to keep you out of trouble.

You can get a lighter piston as a forged.

But again...depends on how you want to use it and what the goals are. With restricted exhaust, head, intake etc....a stroker just makes it run out of breath earlier.

Hyper's allow you to fit wall clearance very tight...but you can do the same with a 4032 forged.

SCAT rods will be fine...but it's tougher sometimes to find the small journal stuff. But too bad....many circle track guys cut their stuff down to that or even Honda rod journals.

If you just want a nice little motor...spend all your money on block prep and torque plate honing as suggested. You'll need to do that on the higher power version also.

JIM

Easy Rhino

I do enjoy doing things myself, but would have to do a lot more homework before I even began to think about porting heads myself How hard is it?

I think I will pass on a roller cam.

I also see no reason to spin it over 6500rpm, and probably not that frequently over 5,000rpm.

Wow, that's a strong high rpm engine.

Thanks for the "L76 is adequate" reset. The engine in the car is all wrong and will likely provide few, if any, parts for the new engine. I have a new to me very clean 870 327 block that's going in and is the base for my new build.

I will need to confirm using a bore micrometer the measurements, and shape of the bores.

The pistons in it right now are flat tops.

Lots of insight there, thanks, and yes, it makes good sense. Lots of arguments for and against use of stock rods - guess I'm still on the fence.

As far as the bore goes, if it needs cleaning up, I'm thinking that I would go the minimum, to leave more room for the future if needed.

There is a lot of homework I have yet to do on the whole business of quench.

Awesome, thanks for the insight.

You guys, predictably, are providing me with more info than I can figure out in a month of Sundays. Keep 'em coming.