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Engine question SBC

Cucv_M1008

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My friend has a motor i am looking at its a 350 it makes 350-375 hp what would it make in torque ? he is looking for the spec sheet but cant find it yet.

His quote to me " I was told by the engine building that was built for the 350 ci midget racing class but it's a 400 in disguise."

any thoughts ?

motor1.jpg

or 2.jpg

tor 3.jpg
 
Not really enough information to go on. It looks to be running GM heads. First thing I would do is get the block and head casting numbers and look them up. Pull a valve cover and see what you are working with. If it's a 400 you should be able to see on the balancer where metal has been removed for balancing.
 
sounds like an rpm engine....I don't think those are built with low-end torque in mind, but rather mid to upper rpm power.
You would need the cam specs, c.r., intake specs (open plenum, or divided) to get more of an idea.
 
a lot of 400s have 3 freeze plugs on the side of the block as well. Whereas other sbc do not, that is an easy way to tell, however some 400s only have 2
 
Pretty tough to hide the required flexplate balance weight and the "400sb only" harmonic balancer ,unless someone spent megabucks having the crank internally balanced with heavy metal,or another crank put in it --they did make "thick" bearings so a 350 crank will work in a 400,but it reduces the stroke,and longer stroke equals more low end torque--short stroke is better for a high revving engine....the casting number on the rear of the block near the bellhousing will identify it as well..
 
He sent me this picture, If i get it i am going to change the carb from a race carb to a 4x4 carb and try to keep the headers. I know i might need to also change the cam. but its a good starting point than build a new motor.

rearmotor.jpg
 
I am not keeping the carb though, its a race carb, so carb suggestions to run until i do a efi system.
 
A Quadrajet set up right is probably the best all around carb..."poor mans EFI" they are called sometimes,because they dont flood easily off road during off camber or hill climbs & desents...

On the block near that casting number there should be a round circle of dots,that indicates the date of production...(sort of like a "clock"--look on google and you'll likely find images of this and info on how to de-code it)..
The lack of numbers in front of the RH head indicates the block was decked or resurfaced at some point and they were ground off--or,it was stolen..:whistle:

Only way to be sure to tell if its a 327 or 350,is to measure the stroke...even if it is a 327,someone could have put a 350 crank in it ,or it may be a 327 crank still...which has a shorter stroke and makes it want to run best at high rpms..
--going by memory I think a 327 has a 3.25" stroke and a 350 is 3.48"..
 
The block numbers say its a 350, the guy my friend bought it from ran it in a race car....I doubt its stolen or a 327. When I get the motor in July I'll know more.
 

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