Value of a 400/402 big block?

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Raider L

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I concur on all points in spades!!!!

I have a bunch of car mags, i.e. Car Craft, Rod & Custom, Hot Rod, Super Chevy, Chevy High Performance, and many others from the middle to late '90's that have all kinds of articles on building up 402's. From what I've read it's what GM called a 396 for insurance reasons. The reasoning behind that was if they said it was a 396, it wouldn't be as much to insure it as a 427 or a 454 which the insurance companies took a very dim view of. For some reason they thought a 396 wasn't as dangerous as a 454 in a Vette or a Chevelle, or worse a Nova. They could just see some 16 year old kid wrapped around a telephone pole, but if the car had a 396 in it he wouldn't be wrapped around it as far.
 

Craig Nedrow

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I was there when they came out.....we all drooled. Been in some very fast 396's. 402 was a .030 over 396. 4.125 stroke shaft makes it a 454, but different from "the" 454, 4.25 bore, 4" stroke.
 

Ricko1966

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Here's a tid bit for you a 396/402 although not huge but here's something to consider your getting longer rods and better heads than any factory sbc. Good heads and long rods make power.
 

idahovette

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I concur on all points in spades!!!!

I have a bunch of car mags, i.e. Car Craft, Rod & Custom, Hot Rod, Super Chevy, Chevy High Performance, and many others from the middle to late '90's that have all kinds of articles on building up 402's. From what I've read it's what GM called a 396 for insurance reasons. The reasoning behind that was if they said it was a 396, it wouldn't be as much to insure it as a 427 or a 454 which the insurance companies took a very dim view of. For some reason they thought a 396 wasn't as dangerous as a 454 in a Vette or a Chevelle, or worse a Nova. " They could just see some 16 year old kid wrapped around a telephone pole, but if the car had a 396 in it he wouldn't be wrapped around it as far."
This statement would depend on the level of the 396 build and The kid driving it!!!!!
 

85K304SPD

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Ricko nailed it. Its like a 383 or 400 SBC with all the better features. Bigger valves, rods, etc... heavy duty and still stock dependable. Sure it is a little bit heavier, but these trucks are already heavy.
 

GTX63

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One of the fastest street cars I ever rode in was a 69 Chevelle with a 396/402. This was in the mid 80s. It pulled the front wheels at will and was a legit daily driver. Times were different.
I'd have no problem snagging one for a squarebody and they are as easy to work on as any Gen 1 small block.
 

Strick

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It's a Big Block Chevy...is there any question? So, if it were a tall deck 366 or 427 I may hesitate to build it for a Square; but a 396 will nestle nicely in the engine compartment. I may be a bit biased as I have 4 396/402 engines and a couple 454's.

HS
 

Turbo4whl

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I concur on all points in spades!!!!

I have a bunch of car mags, i.e. Car Craft, Rod & Custom, Hot Rod, Super Chevy, Chevy High Performance, and many others from the middle to late '90's that have all kinds of articles on building up 402's. From what I've read it's what GM called a 396 for insurance reasons. The reasoning behind that was if they said it was a 396, it wouldn't be as much to insure it as a 427 or a 454 which the insurance companies took a very dim view of. For some reason they thought a 396 wasn't as dangerous as a 454 in a Vette or a Chevelle, or worse a Nova. They could just see some 16 year old kid wrapped around a telephone pole, but if the car had a 396 in it he wouldn't be wrapped around it as far.
So that helps me understand. GM called the 402 a 396 in 1970. In 1971 they labeled it as a 400. That caused confusion with the 400 SB. The last year they finally called it the 402. As far as I know only 3 years as a regular production in the full size sedans.
 

85K304SPD

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Ok, so I just pulled out a 383 and dropped in a 402 in my 85. It is an original big block truck, so it needed a big block back in it. It looks correct now, but not a "big ole'" 454 gas hog. I haven't pulled any loads or anything with it yet, but so far it seems to run well. I feel better about it now.
 

85K304SPD

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Ok, so I just pulled out a 383 and dropped in a 402 in my 85. It is an original big block truck, so it needed a big block back in it. It looks correct now, but not a "big ole'" 454 gas hog. I haven't pulled any loads or anything with it yet, but so far it seems to run well. I feel better about it now.
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ChuckN

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TBH, I’ve been quietly keeping my eyes open for something like that. Mainly, because as much top-end work I’ve done on engines over the years, I’ve never gotten into the bottom end, because I’ve never had to. The marketplace and Craigslist are full of well worn big blocks for relatively cheap, and when the time comes I’d like to pick up something just like this to learn on. Checking tolerances, cleaning it up and running it just so I could have the satisfaction of doing it. Not saying that’s why you would do it @Grit dog but I do feel like there’s a lot of value in these things.
 

GTX63

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So that helps me understand. GM called the 402 a 396 in 1970. In 1971 they labeled it as a 400. That caused confusion with the 400 SB. The last year they finally called it the 402. As far as I know only 3 years as a regular production in the full size sedans.
I bought a 1965 Caprice with one of the first 396 engines. Factory holley carb and solid lifters that came in the 425 hp motor but this one was supposedly, and listed, as the 325 hp engine.
You could purchase a Chevy full size sedan with the 396/402 from 1965 thru 1972.
 

Ricko1966

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On 1970 they bored the blocks .030 making all 396s 402s for the 1970 model year they just didn't bother rebadging the cars. Trucks still got the 396 for 1 more year. Here's a fun question the 366 and the 396 have the same stroke do you think the blocks were cast with enough meat to accept a 396 bore. The 283,302,307,327 small blocks had this same situation. I cannot remember how to tell the difference but the 283-327 blocks had 2 different castings 1 was the same casting just bored smaller so you could bore it to 4 inch the other casting it was hit or miss
 
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Old Guy Bill

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Several years ago I built a sweet ‘69 Camaro.
Bought a 396 with a ‘68 date code & suffix from a passenger car.
Bored 30 over, hydraulic Comp cam, 750 double pumper Holley with a Muncie 4 speed and 12 bolt rear end. That big block would annialate the tires.
I loved that car and it turned heads.
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