small block HP/Torque ratings ?

-
rustytoolss

rustytoolss

Well-Known Member
Joined
Sep 26, 2013
Messages
972
Reaction score
73
Location
Clinton, Ohio
Would anyone have a list/chart showing the stock small block HP/Torque ratings to compare most on the engines including LA/ LA Roller/5.2 & 5.9 magnum for 318s /340s/360s 2barrel and 4 barrel if possible ?
 
mymopar.com has most of them.

some are not 100% according to me

...and you have to calculate the difference between net and gross after 1971
 
811DEF75-BD3D-47AA-9AB2-9CBA47293AC7.png
rustytoolss said:
Not sure what you mean by that "read my sig" ??
Click to expand...
I have to turn my phone sideways to see ones signature.....
 
Thats pre 71 gross HP specs. After 71 they net rated the HP and it looked like it killed the motor.
 
I had a 273/4, spun a rod bearing so i bought a 318 short block and built with all the 273 dress and cam and the 318 was way quicker.
 
I got fingers in all the pies: 273/2 and 4 owner, slant owner, teen and 340 owner, big and small block stroker owner. I never ran a 360 though.
 
pishta said:
I got fingers in all the pies: 273/2 and 4 owner, slant owner, teen and 340 owner, big and small block stroker owner. I never ran a 360 though.
Click to expand...
Gee-Whiz man 360s are the cat's meow,lol.
Now as for me, I've never owned anything bigger than a 360, but lots of the smaller ones.And I got a shed full of blocks to prove it.

Heres going from memory;
Pre-SAE-Net, LAs
318-2bbls were 230/340tq
340-4bbls were 275/340tq
360-2bbls mightabin 245hp
Post LAs
318-2s were like 180hp
340-4s were 240hp
360-4s were 245hp

5.2s I think were 230-EFI
That's all I got

As I recall when the 340s switched ratings, the compression dropped from 10.5 to 8.5, the carb switched from AVS to TQ, and the idle-timing was retarded 5 degrees; and the demons went same or quicker mphs IIRC.
 
Last edited:
Good info AJ. From what Ive read, the 340s were very underrated in order to try and keep insurance premiums lower. Closer to 300+. Not sure how true that is, but Ive read that before.
 
Yeah but that's not what OP asked.
IMO, ratings are just ratings.
I mean, look how much higher a Net rating the 5.2 has over the Net LA318. 50net horsepower?
It ain't in the compression by it self, and it ain't in the cam or EFI by themselves.And I'm thinking it cannot even be those three together.
So where's it coming from? Can the stock Magnum heads make the combo that much better?
Anyway, IMO, ratings are just ratings.
If you build it yourself, you can build any SBM up to .8hp/cid, fairly cheap. .9hp/cid is still factory heads. But 1.0 and more will cost quite a bit more
 
You must log in or register to reply here.
-

Back
Top