400 big block

hey guys its me again.has anyone ever heard of some dropping a 400 big block into a 88 caprice if so,whats the process like? thanks for your help Chevy Boyz!!:grinno:

hey guys its me again.has anyone ever heard of some dropping a 400 big block into a 88 caprice if so,whats the process like? thanks for your help Chevy Boyz!!:grinno:

400 big block? What make? Although Chevrolet advertised one for the 1971 model year, it was really a 402 - and that in turn was a 396 factory overbored .030".

there's not a 400 big block. There's a 366, 396, 402, 454, but not a 400. However there is a 400 small block, which would be the same outside specs as any other sbc.

Correct, the 400-cid was a small block. Its basically a bored 383-cid. The major problem with the 400-cid was that the cylinders were siamesed, which caused the block and heads to overheat.

The overheating potential is really overblown. It really doesn't happen that often, and there are easy things which can be done to minimize or eliminate any overheating problems. Surely, the potential for hot spots is slightly greater, but it's not as common as some would have you believe.

FWIW, if you perform the math, a "402" is actually 0.029" larger in bore (to make it a nice, round 4-1/8" bore) - Close enough.

Which do you really have? The 400 was only made for a few years, too, even though there are a lot of aftermarket siamesed bore blocks out there, and a ton of 406s and quite a few 426 SBCs on the street.

Correct, most Chevrolet NASCAR engines are built with the 4.125" siamesed block (albeit one designed for the purpose). If these can run 500 miles WOT without overheating, the 400 should be able to have a managed cooling capability.

I had two 73 Caprice ragtops which came with 400 small block's. Never had a problem with overheating. The only problem I had with both was baaaad gas mileage; about 10mpg which rivalled my 67 Lincoln Continental winter car I had at the time. With one of them I did however add headers, crower cam, aluminum intake, HEI, Holley 600 carb, shift kit, etc. and managed to boost the milage to 20mpg. The other one I pulled the 400 sbc for a 425hp 454. Mileage wasn't bad at 16mpg, but it sure was a lot more fun to drive!

I rebuilt a 400 sb into a high performance 406 which made it into a few of my Chevys :lol:. I was aware of the potential for overheating especially with boring it out .030 . I installed a 4 core radiator and used a high flow, high performance cooling fan( 5 blade) with no problems.

I looked through a beautiful "coffee table" book on the SBC today at Borders. It indicated that the 400 SBC did not really put out much more HP than the 350 and got worse gas mileage. When it came out, Motor Trend panned it.

The book is a real nice item, has a lot of history on the development and deployment of the SBC through the years, although I caught some ommisions, and the info was sketchy at times. Lots of pics of great cars.

I go in from time to time and will get the author and title.

I looked through a beautiful "coffee table" book on the SBC today at Borders. It indicated that the 400 SBC did not really put out much more HP than the 350 and got worse gas mileage. When it came out, Motor Trend panned it.

The book is a real nice item, has a lot of history on the development and deployment of the SBC through the years, although I caught some ommisions, and the info was sketchy at times. Lots of pics of great cars.

I go in from time to time and will get the author and title.

The 400 was never a "Horsepower" motor - it was not designed to rev high with its 3.75" stroke and 4.125" bore. What it did, and did well, was pound the asphalt with gobs of low-end torque to spare. That's one reason why it was popular in some trucks until its discontinuance in 1980.

guy in my neighbourhood did it, actually pretty cool, btw guys he learned the point the first time its a 402 not a 400, no need to keep repeating it

so the "400 big block" is actually a 402?am i right? is there a way to run a 402 or even a 454 i a 88 caprice?

where can i find a nice set of vogues from for cheap?

Correct, the 400-cid was a small block. Its basically a bored 383-cid.
no, the 383 isnt a block size. its a 350 with a longer stroke.

400 is actually a 389 pontiac engine bored over. or at least the original one was. idk much after that.

id say its a 402, because chevy never made a 400ci mtor other than a sb

id say its a 402, because chevy never made a 400ci mtor other than a sb

In 1971, Chevrolet offered its 402 big block as a "400 big block" which is where the confusion comes in. You're right, there was never an official 400 big block, but Chevy did market one for one year.

In 1971, Chevrolet offered its 402 big block as a "400 big block" which is where the confusion comes in. You're right, there was never an official 400 big block, but Chevy did market one for one year.

and its not a 383 bored over, cause thats not a real block XD its a stroked 350

and its not a 383 bored over, cause thats not a real block XD its a stroked 350

#1, where did that come from, and #2, what is XD?

The 383 is a BORED and STROKED 350. It's generally a 327/350 block bored .030" over, with a ground-down 400 crank (the 2.65" mains ground down to 2.45").

The 3.75" (400) stroke in a standard bore 350 yields 377 cid.

In 1971, Chevrolet offered its 402 big block as a "400 big block" which is where the confusion comes in. You're right, there was never an official 400 big block, but Chevy did market one for one year.

Good point! I really didn't realize that they marketed a 400 BBC..... Kind of a dumb move to do that, that's really confusing.

Here is the info on the book I mentioned earlier. History of the SBC, lots of pics of cool Chevys, etc.

http://www.horsepowerbooks.com/Store/ProductDetails_23065.ncm

In 1971, Chevrolet offered its 402 big block as a "400 big block" which is where the confusion comes in. You're right, there was never an official 400 big block, but Chevy did market one for one year.
yes your are right there, btw a bb swap wouldnt be to hard i dont think, the boxy caprices have quite a bit of room under the hood

Si is correct about the 4" bore strokers. Another, even more common option currently is to use aftermarket stroker cranks with 350 mains (2.45") and bobweights already trimmed a bit for cam/skirt clearance. An old school option was to align bore the 350 blocks for 2.65" mains, since the boring is a good idea to assure a straight crank on an engine build anyway. The strangest combinations were grown from that, including cast crank strokers with 4-bolt straight or splayed main caps, 2-bolt strokers, strokers with both 6.0, 5.7, and all sorts of other rod lengths, pin heights, deck heights, etc.

Blown - The bubble B-Bodies have even more room than the boxes.

there was a guy who was running a 454 in an 83 2 door caprice here. he had it set up with side pipes... sounded really nice, but the frame couldnt handle the torque, it twisted. not saying this will happen to all, just a word for the wise...

when i asked how hard it was to put it in he said it wasnt too hard, he compaired it to replacing the 305 with a 350

there was a guy who was running a 454 in an 83 2 door caprice here. he had it set up with side pipes... sounded really nice, but the frame couldnt handle the torque, it twisted. not saying this will happen to all, just a word for the wise...

when i asked how hard it was to put it in he said it wasnt too hard, he compaired it to replacing the 305 with a 350

A 9C1 frame under a boxy will likely prevent the torque twist issue (I haven't seen this since a V8 in a Vega years ago) with the big block.

Inasmuch as installing the engine, what you will need are new mounts for the accessories such as alternator, power steering pump, smog pump etc., because the stock small block brackets won't work. You will also need the pre-cat exhaust system (generally the Y-pipe and manifolds) because the SB parts won't work. However, the transmission bolt pattern is the same, as is the engine mount locations. Even the SB distributor will work. If you do this and don't have a 9C1 frame, replace all of the body mounts with polyurethane mounts and brace up the front a little better.

The only boxies that could have a 9C1 frame are the 1980-1985 Impala and the 1986-1990 Caprice. No 1980-1985 Caprice will be so equipped. Of course, the car has to be a 9C1.