How do you tell if it's a 305 or a 350?

[McCoyAZ]

I am building a 64 C10 Stepside and I ran across an 82 fleetside silverado today for $1000. I might buy it for the parts.

I want a 350 motor and the guy does not know which motor is in this truck.

How do I tell what it is?

[Redcap]

Run the numbers on the back of the block.

[McCoyAZ]

I was hoping I could know from looking while I was standing at the truck?

Any certain number set identify the motor as a 350?

It is a long drive out there and back.....

[406 Q-ship]

Decoding the engine is the only true way to know for sure. Visually there is nothing that will give it away.

[motornut]

some may have it by the engine mount 3 0 5................3 5 0
one thing i did notice my truck
stock came with a 305, 2 line fuel pump
stock if it came with a 350 is a 3 line pump.....
not sure if that always applies
or try looking here......this is one

[406 Q-ship]

010 block means it is a 4.00 bore block so that would rule out a 305, but not all 350's have 010 blocks. The number of fuel line has to do with emissions and will not ID a 350/305. Run the codes on the pad in front the right cylinder head that is behind and kind of under the alternator. Checking the codes is the only sure way, short of pulling the heads off the engine.

[rwhit57]

I have noticed some 305's have 2 sets of bolts for the starter. I don't know if this is true on the early ones or not.

[motornut]

the reason i said about the lines was i just bought one
and i was told by Carter the two line pump was not used on a 350
but he said the third line it was to "return fuel to the tank"
when i asked if the two line will work on a 350 he said it should


but of course this means to it can be reversed i guess.....
meaning you could put a 3 line pump for a 350 on a 305 too then

[McCoyAZ]

I found the easiest way in the world to determine what motor was in this truck......

I read the tag on the ait breather. 5.0 305

[DetroitDan]

what about the vibration damper? Ive always told them apart that way. One is fat (I think its 305) and the other is thin. Obviously that could have been switched too, but generally if you're looking at an old dirty motor with an old dirty balancer it's a fairly safe bet.
Could be Im wrong and have some bad info, but the handful of motors I've checked have turned out to be right when checked that way.

[taank]

Usually it's cast on the back of the block.
Posted via Mobile Device

[sumran]

Originally Posted by taank

Usually it's cast on the back of the block.
Posted via Mobile Device

Mine has 5.0L cast on the block next to the casting number.

[russgt]

an 010 block is a 350

[primrrd]

I think that the exhaust manifolds were different too. I had one that was cracked, and bought a replacement "blind" ...it turned out it was a 350 and different than the ones my truck had.
(81 c10)

[Axle]

Reading the casting number on the block will be the only sure way to know what you are getting. Print out the block casting number list to take with you as a guide over at nastyz28.

Consider the potential amount of engine swaps that could have been done over time, casting number is your only sure fire way to i.d.

My truck started out with a 305/700r4. That turned into a 350/700r4 w/the 5.0L manifolds and sheet metal. That turned into a 350/350 combo, and somewhere along the line I put my '73 passenger car exhaust manifolds on it. Looking at anything but the casting number isn't going to let you know what the engine is. Unless you are familiar with how it is supposed to be, you may note something isn't quite right, but won't be able to put your finger on it without something to reference.

Alex.