396 Chevy Build

[dulcich]

Hey Bangshifters,
I've got a 396 BBC project that came into the shop. Engine is for one of the top suits at Source, and the car is a 70 SS 396 Chevelle. Got a big box of engine and just popped the lid and tore it down. I am planning the build right now. It's not the numbers motor for the car being restored.

So, I'll post a rundown on what came out of the box, and then the build goals, and then see what kind of input you guys might have on the build. I've got some ideas of where to go with this build, but thought it would be interesting to share ideas with you guys and get some input and thoughts, even if it is just to get a GM crate engine instead. Here is a rundown of what was in the box I got from JB:

*Engine was already fully disassembled and mocked back together in the crate. Pistons already out.

*No exhaust manifolds, front cover



BLOCK:
1968 396 block by casting numbers

1966 396 325hp Chevelle engine by numbers stamping code: ED; code does not match up to block casting number, probably restamped at some point.

Block bored .030 from 4.095 to 4.125. Block needs overbore to 4.155 (.060-over). Not a really thick wall block by visual inspection. Recommend sonic check before proceeding with rebore.

Main caps appear to be mismatched set from more than one block. Recommend replacing main caps or careful inspection and line hone or line bore.

CRANKSHAFT:
Factory 1968 forged 3.76-inch stroke crank. Crank .020-inch undersized on mains, .030-inch undersided on rod journals. Needs regrind. Recommend replacing crank because it is already machined to third undersize.

RODS/PISTONS
Stock press-pin rods and GM +.030-inch cast pistons. Pistons will need to be replaced, recommend new aftermarket rods.

CAMSHAFT/VALVETRAIN
Stock 1966-style (grooved journal low-lift hydraulic flat tappet cam and stock style valvetrain. All worn out. Recommend upgrade to hydraulic roller.

CYLINDER HEADS
Oval port 109cc closed chamber iron. 2.06/1.72 valves. Mismatched set casting numbers 3931063 (1969-1970) and 3917215 (1967-1969). Recommend replacing with aftermarket aluminum small chamber oval port heads. Need to research availability for small bore block. Thinking Edelbrock 454-O here.

INTAKE MANIFOLD
Cast iron stock Quadrajet intake number 3865287. Recommend aftermarket aluminum low rise dual plane.

CARBURETOR
Quadrajet number 7040205; 1970 Chevrolet application. Rebuild or replace with new Holley.

SHEETMETAL
Stock style oil pan heavily dented at sump and dipstick fitting. Recommend replace with new stock replacement pan. Stock chrome valve covers rusty and pitted. Recommend new replacements. Stock timing cover missing.

DISTRIBUTOR
OEM single point Delco unit. Well worn. Recommend replacing with aftermarket electronic unit.

GENERAL RECOMMENDATION
Since the crank rods and pistons are all being replaced, I would suggest upgrading to a 4.00-inch stroke (stock 454 spec) aftermarket crankshaft. This crank stroke along with a 4.155 bore will result in 434CID for improved torque and drivability. Use with 6.385 connecting rods and custom forged pistons.

Recommend replacing with aftermarket aluminum small chamber oval port or rectangualr port heads. Need to research availability for small bore block. Edelbrock 110cc oval ports? Rectanglar port heads/ Holley 4150 carb and aftermarket aluminum intake would be the way to go to resemble a 1970 396 375hp engine rather than the low performance 325hp engine we are basically starting with.

Recommend upgrading to a mild hydraulic roller cam. I will spec a custom cam that will idle nice and make excellent power. Will also put together a durable valvetrain using components from Comp Cams. Cam specifications will be influenced by the choice of exhaust system (headers or OEM manifolds).

[Barry Donovan]

old tough one.
3 grinds.
just the hydraulic upgrade and alum heads...
it should go farther than ever.
being that old, what about optical pickup.. by crane(?)
get out of the old magnetics.

[38P]

Is the goal to look "stock?"

How much bread does the "top suit" want to spend? Is it supposed to be "budget" (assuming so, given the use of a non-matching 396 (a giveaway lump) instead of a larger "core" block)

How's he going to use the car? (Driver? Show car? Open track? street/strip? Bracket race?)

Is this build for editorial content in any SIM publication?

Are fuel economy or emissions any concerns?


Unless it's a stock-appearing resto build, I'd suggest some turbos on a mill that small. That would make it more interesting and have more driveable "area-under-the-curve" than any other way of building it. Besides, there aren't enough power-adder builds in EM, IMO.

Stroker crank idea is okay (sort of common practice now). Hydraulic roller is okay (ditto) . Edelbrock heads are a safe choice for the street.

Perhaps an update of Pop Rod's old "Project Engine" series (a hopped-up 396 from thirty years ago) is in order. But turbos would be more interesting.

[dulcich]

Good points Barry. Like the mags and hate the light, beams and there influence what they are. I will side with darkness here.
-dulcich

[Barry Donovan]

Good points Barry. Like the mags and hate the light, beams and there influence what they are. I will side with darkness here.
-dulcich

maine got me on the magnetics...
inventors kept it a world standard for their own reason.

even the sun flips.

[dulcich]

Is the goal to look "stock?"

How much bread does the "top suit" want to spend? Is it supposed to be "budget" (assuming so, given the use of a non-matching 396 (a giveaway lump) instead of a larger "core" block)

How's he going to use the car? (Driver? Show car? Open track? street/strip? Bracket race?)

Is this build for editorial content in any SIM publication?

Are fuel economy or emissions any concerns?


Unless it's a stock-appearing resto build, I'd suggest some turbos on a mill that small. That would make it more interesting and have more driveable "area-under-the-curve" than any other way of building it. Besides, there aren't enough power-adder builds in EM, IMO.

Stroker crank idea is okay (sort of common practice now). Hydraulic roller is okay (ditto) . Edelbrock heads are a safe choice for the street.

Perhaps an update of Pop Rod's old "Project Engine" series (a hopped-up 396 from thirty years ago) is in order. But turbos would be more interesting.

It is going to be "stock appearing" and a basic street performance car. Turbos? Yuck! I strongly object to the idea for a resto type build, totally out of character for the history of the car. Good suggestion, but not in keeping with a resto style build. I want it to look like a stockish 396 under the hood, but with substantially more power than a stock 325 horse 396. Not many 396 builds online or in publication at all. Not many head choices for the 396, considering the smaller bore. The E-heads selection is more because it is apporpriate than "safe." Main goals are driveable, reliable, and looks traditional. Looking for about 500-550 hp, relatively stock appearing, and super driveable.

[dulcich]

maine got me on the magnetics...
inventors kept it a world standard for their own reason.

even the sun flips.

Fields oscillate random waveform irregularities. I'm thinking Pertronics.
-dulcich

[38P]

I'd like to see a test on Rhoads RL8178XRB V-Max roller lifters here, as well. Like all hydraulic roller retrofits, they're kind of pricey, but the variable duration angle is always interesting.

[38P]

Obviously if its a resto build, then you're stuck with a single four barrel and some look-alike parts (Yawn. Zzzzzz)

That being the case (550 h.p. with Barrett-Jackson "stock" looks), I'd be more tempted to paint the aluminum parts orange (Edelbrocks okay with some strategic grinding off of the labels and go with a Quadrajet instead of another me-too Holley (http://www.cliffshighperformance.com/ . . . . can easily build a Q-Jet that will feed such a modest mill) for the sleepy look.

550 out of a 325-hp clone is a lot more impressive than 550 out of a 375-hp clone.

But go with as many cubes as humanly possible . . . and the previously-suggested Rhoads (that is unless somebody's slathering on the product-placement swag)

[38P]

Not many 396 builds online or in publication at all. Not many head choices for the 396, considering the smaller bore. .

That's why it's a "giveaway" lump. Unless it's free, it costs nearly as much to build a 396 as it does to build a stock-block fatter rat. All that weight and cost for relatively so little "bang." Thus, the 396 is mostly for the numbers-matching crowd (or maybe uber cheapskates and a few nostalgia freaks), and is not a prime choice for a performance engine anymore.

Besides, when you see any rat in anything but a pure resto, you automatically assume its at least 454 or larger.

[dulcich]

Some good thoughts, Outsider. I'm not sure about putting in as many cubes as possible; I think the 4-inch crank is about right for this build... trying to go nuts on the cubes comes with compromises that don't make too much sense to me in this kind of build. As far as "product placement" you might be surprised that no one ever advises or directs me as to which products to use in a build.

I like the Q-jet too, but building it to a 375 horse appearance with the Holley would be cooler IMO. Back in the day my '69 383 SuperBee would not fear the tame 325 hp 396... The 375 hp version had so much more street cred.

[VTJUNK]

Do the edelbrock heads work on a 396? Seems a small bore engine, combined with a big valve head would have valve shrouding issues, and if I'm not mistaken that was always an issue with the 396 engine.

[38P]

Back in the day my '69 383 SuperBee would not fear the tame 325 hp 396....

Which is why I say issuing some "cold-cocks" with a 325-look baby Rat sleeper is better than overt profilin' with a "375" that even the densest mope will assume is a 500+ h.p. mill. . . .

I'd also like to "see" (or perhaps, not actually see) a well-hidden N20 system on a sleeper.

Of course, if Mr. Big Suit wants to cruise night/lawn chair profile instead of lay low, all that aluminum bling in plain sight is certainly a popular way to go.

(And yes, I realize how inconsistent all this sleeper talk is with the earlier, extroverted turbo suggestion. But if it's got to look "stock," it really ought to sneak up on 'em with serious fury. If not stock, then I say blow 'em away.)

[38P]

Do the edelbrock heads work on a 396? Seems a small bore engine, combined with a big valve head would have valve shrouding issues, and if I'm not mistaken that was always an issue with the 396 engine.

[Beagle]

I'm guessing the Rovals will fit and you'll have enough space on the top ring to maybe unshroud the cylinder a little? 10.0 or a little more static, 224* ish @ .050 cam should make for a nice tire shredding device.. maybe like an XR276HR comp cam?