What have I gotten myself in to?

[Zbishop94]

I just recently acquired a 396 BBC from my uncle. I've been reading and all I've found is confusion. There are a gazillion different 396's. My uncle said it came out of a '78 heavy half. But to my undestanding 396's stopped production in '70. Then I read after that they were actually 402's but marketed as 396's. Also, I'm anxious to start squeezing power out of this thing but I'm very new to engine building. Been doing my research and I just want to be sure of what I have before I start buying parts. Any info/suggestions will be given full consideration. Also any tips and pointers for a beginner will be greatly appreciated
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[Alex V.]

The first thing to do is get the block casting number (near the back of the engine on the bell housing flange) and stamped codes (on a flat surface at the front of one of the heads) off of the block and look them up. If it is a 396 it isn't a '78 - the 454 replaced the 396 in '73. It'll never get more than 14 MPG, more likely 10-12, but the big block Chevy in general is legendary from the high-perf applications it was used in and was Chevy's staple heavy-duty engine for a number of years after Ford and Dodge had diesels as their truck's big engine option. First use of the 396 was in '65? Corvettes, which gave way to the 427 in '66.

[Captainfab]

The 396 was used from '65-'69 in Impala's, Chevelle's, Camaro's, Corvette's and trucks. Starting in '70 the bore was increased by .030 making it a 402. The 402 was in use '70-'72. The original big block engine in a '78 C10 would have been a 454. I agree that you need to check either the casting number or the suffix code on the front of the block to know what you have.

[Zbishop94]

If I remember right the block number 3955272. I did a little research on that and apparently I can't pin down exactly what it is until I open it up and see if it's a 2 or 4 bolt main.
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[alsriv2]

Be aware, as an owner of a very nicely built 396, parts are not going to be cheap to make your engine right. Machining costs and finding parts for a 396 can be pricey. Looking back, I probably should have gone the 454 route, but I had a 396 and stuck with it.
This weekend, I think I will be in a position to finally hear it run for the first time since the Dyno was done 4+ years ago. Work has gotten in the way of completing my '69 assembly.

[Zbishop94]

What kind of machining would you say is a must? I understand this hobby is very expensive. I'm in no rush. Like I said I'm new and I'd hate to blow it up because I didn't pay attention to what I was doing.
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[Zbishop94]

Originally Posted by Captainfab

The 396 was used from '65-'69 in Impala's, Chevelle's, Camaro's, Corvette's and trucks. Starting in '70 the bore was increased by .030 making it a 402. The 402 was in use '70-'72. The original big block engine in a '78 C10 would have been a 454. I agree that you need to check either the casting number or the suffix code on the front of the block to know what you have.

Where might I locate the suffix code?
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[Captainfab]

It should be on the pad in front of the passenger side head. The 454's had the suffix code directly above the timing chain cover on a little machined pad.

Originally Posted by Zbishop94

Where might I locate the suffix code?
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[Ironangel]

Need to check that suffix code, that might be an L34 396 block. The casting number checks to either 1969 396 or 402 blocks, they can be either 2 or 4 bolt mains. Heres a link, http://www.roadsters.com/bbc/ Dont trip if it's a two bolt, four bolts dont come into play until you start pushing 7000 rpm and/or pulling heavy loads at 4000 + rpm...The suffix code may or may not pin point what you have so be prepared to measure bore diameters, run the head casting numbers and drop the pan. Check the crank number as well. Heads will depict much...Sounds like you may have made a good score? My 396 came out of a 1969 SS El Camino, 350HP L34 motor w/2-bolt mains.

[Dead Parrot]

Even after you id the block, you need to find out what's inside before you even think of buying parts. Insides might be a pile of rust and corrosion due to water getting in somehow. Or #8 cylinder might have a wasp nest in it. Or a hole in the side. It was pulled out of the donor vehicle for a reason.

Might consider picking up a scrap SBC to practice your disassembly and reassembly skills on. Any accidents won't hurt anything since it was scrap to start with. The basic tech between a SBC and BBC is very similar. You can also acquire the needed tools, lifts and stands while you practice.

Decide what you want to use the engine for. A BBC built to make power at 4000+ rpm might not be the best choice for an in town daily driver. Flip side is an engine built for brute towing power might do poorly at a drag strip.

[Zbishop94]

Originally Posted by Dead Parrot

Even after you id the block, you need to find out what's inside before you even think of buying parts. Insides might be a pile of rust and corrosion due to water getting in somehow. Or #8 cylinder might have a wasp nest in it. Or a hole in the side. It was pulled out of the donor vehicle for a reason.

Might consider picking up a scrap SBC to practice your disassembly and reassembly skills on. Any accidents won't hurt anything since it was scrap to start with. The basic tech between a SBC and BBC is very similar. You can also acquire the needed tools, lifts and stands while you practice.

Decide what you want to use the engine for. A BBC built to make power at 4000+ rpm might not be the best choice for an in town daily driver. Flip side is an engine built for brute towing power might do poorly at a drag strip.

Right, I haven't even thought about parts yet. Still in the tear down process. Getting a stand tomorrow. Putting it back together is what I'm nervous about putting it back together. Getting a small block may be handy in that respect. Thanks for the idea. Do you think it would be wiser to just check it out, clean it up, buy gaskets, rings and bearings and see how she does?
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[Zbishop94]

Originally Posted by Ironangel

Need to check that suffix code, that might be an L34 396 block. The casting number checks to either 1969 396 or 402 blocks, they can be either 2 or 4 bolt mains. Heres a link, http://www.roadsters.com/bbc/ Dont trip if it's a two bolt, four bolts dont come into play until you start pushing 7000 rpm and/or pulling heavy loads at 4000 + rpm...The suffix code may or may not pin point what you have so be prepared to measure bore diameters, run the head casting numbers and drop the pan. Check the crank number as well. Heads will depict much...Sounds like you may have made a good score? My 396 came out of a 1969 SS El Camino, 350HP L34 motor w/2-bolt mains.

Actually, we did measure the bore. Came out to 4.094 if I remember right so it would be a 396 then.
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[Zbishop94]

Update: It is a 2 bolt main. Still haven't found the suffix code I don't think. Must be hid under all this gunk I'm trying to clean off. What's the format of the code going to be?
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[Zbishop94]

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[Zbishop94]

Also, heads are #3933148. Truck heads. Oval port. Open chamber. 112cc
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