Bore/Stroke of an Impala 409?

[NoWorries]

Hey, I can't find this info anywhere... The closest thing I've found is a 400 with a 0.040 inch overbore...but a factory car wouldn't come with a bore over standard, would it? I found that a 4.030 bore with a 4 inch stroke would equal 409 CI, but that is a lot of stroke for a 350 block. Thanks. :) Oh, and BTW, I'm looking into starting this for my future 1994-1996 Impala. Thanks. :)

[mountainmotor]

Are asking about a small block 400 bored to 406 ci?

http://www.ridgenet.net/~biesiade/Specs.htm#Trans


[Modified by mountainmotor, 3:29 PM 1/17/2002]


[Modified by mountainmotor, 3:31 PM 1/17/2002]

[NoWorries]

Thanks for the link. :)

I definitely want a 409 if I'm going to go that big, just for the Nostalgic value. :)

Where would one go about getting a block that will bore to 4.342 inches? I'm assuming that would have to be a 400(4.125 inch) bored way out with a sleeve to make sure you don't hit the water jackets? Or is the 4.342 indicitive of a Big Block?

[chaos on wheels]

"She's so fine, my 4 0 9". Isn't that block a predecessor to the small-block Chevy from the 50's and 60's?

This one came up came up first on google (but DIDN'T work for me): http://members.spree.com/entertainme...age_index.html

This is another from google with info on Impalas http://www.55-57chevys.com/coccc/art...6/65asty1.html

[clem zahrobsky]

1971 to 73 409 has 4.312 bore X 3.5 stroke :chevy

[LPDesRoche]

I'm pretty sure you can't just make a 409 with a regular block of any type. It was a special block all together. You wouldn't just be into the waterjackets, you would be in the next cylinder over. :eek:

[clem zahrobsky]

the 1958 348s and the 409s were know as W blocks and were used up to 1964 in full size cars and trucks,never in a corvettes. in 1963/64 these engines were stroked to make them 427 cu in for special drag race impalas called Z-11 that had aluminum body parts. :chevy


[Modified by clem zahrobsky, 9:29 PM 1/17/2002]


[Modified by clem zahrobsky, 9:30 PM 1/17/2002]

[gcrouse]

Wasn't the 409 a big block? A large bore, short stroke variant of the 396-427-454 series?

[The Green Rocket]

There is no way to make a "good" 409 LT1 for your future '94-'96 Impala. Either a 4.030 bore x a 4.0 stroke for 408.18 cubes, or a 4.1 bore x 3.875 stroke for 409.28 cubes. Both ways have their own set of problems, but you are right that it would be too cool to have a modern 409 Impala SS.

For everyone else, sigh...ok, I guess this isn't the classic Chevy forum - but is the 409 really that forgotten that its basic facts are unknown to Chevy enthusiasts?

The 409 basics:
1) The small block, introduced in the '55 model year, preceded the 409.
2) Yes the 409 evolved from the "W" series engine introduced in 1958 as a 348 cid.
3) The 409 was introduced in late '61 in very limited numbers, and was last offered in the '65 model year (in a limited basis in the early part of the
production run).

409 advanced:
Did you know that a 454 crank can be machined to fit in a 409 block? With a .030 overbore that yields 473 cubes, with a .060 overbore that yields 480 cubes, etc. I've seen this done, some day I may just do one for fun in a '59 - '62 Impala.

Thomas