Value of a 400/402 big block?

[Ricko1966]

Chevrolet Engine Block Challenge - Hot Rod Magazine

We have a Chevrolet engine block challenge, pitting a 408-inch small-block up against a 408-inch big-block. - Hot Rod Magazine

www-motortrend-com.cdn.ampproject.org

 

[idahovette]

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

Yeah, I had a .125 over 283 for about 9 months.......then it was a MISS.....side pf the cylinder wall caved...no water, BUT NO compression!!!!

 

[Ricko1966]

Chevrolet Engine Block Challenge - Hot Rod Magazine

We have a Chevrolet engine block challenge, pitting a 408-inch small-block up against a 408-inch big-block. - Hot Rod Magazine

www-motortrend-com.cdn.ampproject.org

I found this for you grit and anyone else concerned, I got a couple of comments though your biggest advantage on bbc vs. sbc is the bbc has long rods and better heads.It would have been a good place to have made both engines run stock heads. Now someone was talking about building some bbc with some headers and I said they were too big for what he was building,look at what the wrong headers do to a bbc. Last check the E.T s yea there's a weight difference but not enough weight to slow the big block down.

 

[ChuckN]

I found this for you grit and anyone else concerned, I got a couple of comments though your biggest advantage on bbc vs. sbc is the bbc has long rods and better heads.It would have been a good place to have made both engines run stock heads. Now someone was talking about building some bbc with some headers and I said they were too big for what he was building,look at what the wrong headers do to a bbc. Last check the E.T s yea there's a weight difference but not enough weight to slow the big block down.

Good read. Makes me even more excited to build a budget BB one day.

 

[Ricko1966]

https://www.motortrend.com/how-to/chevrolet-lied-stone-stock-1969-l78-396-big-block-makes-50-hp-more-than-factory-rating/

 

[Turbo4whl]

https://www.motortrend.com/how-to/chevrolet-lied-stone-stock-1969-l78-396-big-block-makes-50-hp-more-than-factory-rating/

Right around this time is when the manufacturers recalculated HP to lower numbers because of insurance costs.

 

[idahovette]

Right around this time is when the manufacturers recalculated HP to lower numbers because of insurance costs.

Still didn't help much....really got hammered by the Insurance company on my 70 LS6.......about a thousand bucks a year.....I was barely 21 and it HURT!!!!!!........really cut into my beer money...........lol

 

[Travlr]

I know there are better options for building big power, but say a guy had an opportunity to get a good running 400 big block out of a ‘72 C10 for say, cheap….
Seems like a cool engine to drop into any square. Particularly an older one.
Obviously it’s worth whatever a decent running takeout motor is at a minimum, but cool factor, semi-period correct, and a big block…
I have no current use for it, but seems like I can’t pass it up for a couple hundred bucks considering my buddy is looking to get it out of his shop.
If I don’t take it, he’s liable to trade it for a set of headers or something….

402 was only made one year if I remember right, 1970. Kind of a rare engine I guess.

This from an internet article: Beginning in 1970, Chevy decided to bore the 396 out to make a total displacement of 402 cid. No vehicles had the original 396 after 1969, with the exception of the Chevy C/K trucks, which had it until 1970.
Yet, while Chevy may have upped the displacement to 402, the marketing department evidently didn’t get the memo. Chevy continued to brand the new 402 as either a 396 big block or as a new “Turbo-Jet 400.” To make things even more complicated, there actually was another 400 cid small block engine. Chevy marketed the small block as the “Turbo-Fire 400,” to contrast with the Turbo-Jet. In 1972, Chevy finally cut the ******** and started referring to the LS-3, the only 402 left, by its proper displacement. They then promptly discontinued the engine the following year.

 

[Turbo4whl]

Still didn't help much....really got hammered by the Insurance company on my 70 LS6.......about a thousand bucks a year.....I was barely 21 and it HURT!!!!!!........really cut into my beer money...........lol

My insurance dropped down when I turned 25. I guess I was now responsible

 

[Turbo4whl]

402 was only made one year if I remember right, 1970. Kind of a rare engine I guess.

This from an internet article: Beginning in 1970, Chevy decided to bore the 396 out to make a total displacement of 402 cid. No vehicles had the original 396 after 1969, with the exception of the Chevy C/K trucks, which had it until 1970.
Yet, while Chevy may have upped the displacement to 402, the marketing department evidently didn’t get the memo. Chevy continued to brand the new 402 as either a 396 big block or as a new “Turbo-Jet 400.” To make things even more complicated, there actually was another 400 cid small block engine. Chevy marketed the small block as the “Turbo-Fire 400,” to contrast with the Turbo-Jet. In 1972, Chevy finally cut the ******** and started referring to the LS-3, the only 402 left, by its proper displacement. They then promptly discontinued the engine the following year.

402 made 3 years 1970, 1971 & 1972 in sedans.