Stock 1972 sbc 400 specs?

[Baged72]

Just curious what was the horsepower and torq in a stock 400 from 1972?

My motor is no longer stock but im wondering how much i might have added to its original numbers...
I am talking about a 400 sb not the 402 bb.

[bigsnookmaster]

I believe it's about 265hp, and 400 lb.ft on the torque.

[too much stuff]

And just so you know, the 400 small black wasn't available in these trucks.
HP and torque can vary quite a bit depending on the application.

[Baged72]

The 400 didnt come in these trucks??
What did they come in then?

[OhOneWS6]

In 72 small block was a 350, big block was a 402 that was badged as a 400

[Camaro_nut2001]

Originally Posted by Baged72

The 400 didnt come in these trucks??
What did they come in then?

The 400 sbc came in alot of the impala's, station wagon's & so forth. They are a real torque motor so check your heavier car's. I have an unmolested 72' 2bolt 400 out of my Papaw's 72' Impala out in the garage that I plan on building one day for a 73' Camaro project. Hang on to your 400 as they are getting pretty rare and you can make some super fast reving torque out of these motor's. JMO.

[Baged72]

My 400 is already in my truck, it has aluminum intake, 240/430? comp cam, 600 holley, headers, HEI Ignition, Comp Cam Roller Rockers, Double Roller Timing Chain, i was just trying to figure out some hp/torq #'s

[OhOneWS6]

Originally Posted by Baged72

My 400 is already in my truck, it has aluminum intake, 240/430? comp cam, 600 holley, headers, HEI Ignition, Comp Cam Roller Rockers, Double Roller Timing Chain, i was just trying to figure out some hp/torq #'s

How do you know it's a 400? What are the casting numbers?

[Baged72]

I know its a 400 because the original owner told me it was and 2nd i did google the casting numbers but... i dont know them off the top of my head, my truck is up north at my shop.
It is a 400 though.. i researched it many times.

[OhOneWS6]

Originally Posted by Baged72

I know its a 400 because the original owner told me it was and 2nd i did google the casting numbers but... i dont know them off the top of my head, my truck is up north at my shop.
It is a 400 though.. i researched it many times.

Those casting numbers should tell you what it came out of. You can use that to look up HP/TQ ratings.

[Baged72]

I remember looking up the numbers before but i thought it just gave me a range of years it was produced not what actual car it came in and i could of sworn it said it was a truck motor. Maybe i am wrong...

[too much stuff]

The casting number won't tell you what it came out of. You will need the code off of the front pad. That will be a stamped number/letter code in front of the pass side head. That should tell you what it came from. The 400 did come in trucks after 72.

[Beuford]

Hi "Baged" I don't think these "Deskyop Dyno" numbers are infalable but I played with a bunch of cams and compression figures and the numbers do reflect the different components wether they are dead on or not. I'm guessing not....but I've played with different grinds and components on several engines and always been satisified with the results. Nothing beats the real dyno.

PM me if you want -I'll send you the print out.

[capev86]

the 400 was an awesome engine. only problem is most came equipped with a 2 barrel which seriously limited performance potential. if you are rebuilding one, be sure to have (or have machined) cross drilling in both the block and the cylinder heads to compensate for the siamese cylinders that don't have water jackets for cooling. the 2 bolt engine block is stronger at the bottom end.

my dad put a 406sbc in his 84 burb back in the mid 90's for trailer towing. the truck was a 2wd with 3.73 gear and overdrive and he swapped the q-jet and manifold over from the original 350 and kept the restrictive exhaust for practicality sake. it still ran awesome and got 16+mpg without retuning the carb. the only problem was the engine was a '77 model year and had leftover heads with a cross drilled block. towing our trailer on a test run cracked the heads. with the proper cross drilled cylinder heads installed the engine performed beautifully on a month long trip out to Yellowstone and back. the burb went like an over sized camaro and was tons of fun on solo runs. we pulled a few years back when my dad junked his (rusty) truck and saved for a project......which turns out to be my 72 burb 3/4 ton with 3 speed column manual and (soon to be) 4.10 gear swap.

the 307 in my truck (and 327) have a 3-1/4" stroke, the 305/350 have the more desirable 3-1/2" stroke and the 400 has a 3-3/4" stroke. if i didn't have my 406 and my 72 burb had a lot more than 74,000 miles i'd put a 400 crank in that 307 and build a good economy stump puller. the 383 is another good example of power with economy. there is a company out there that is building wide skirt small block's that use a special 4" stroker crank (and very big pistons) and you can get a vintage style small block chevy punched out to 472 cubic inches.....ouch!!