so guys i need to know. if someone told you they were selling you a car with a 350 not the stock 305 whats the best way to tell the difference. save actually finding the motor numbers

Numbers on the heads maybe? Receipts? Numbers on the motor is thebest way... if they have a problem with you getting the #s off the engine... Id say dont buy it...

The ONLY way to know for sure is to get the numbers off the block - they are driver side, back end of block, on the top - impossible to see almost. There is no other way.

Agree. if there not welling to get a casting number off the block forget it.
and if they dont know what a casting is or where to find it then wow dont even give that car or its owner a 2nd thought. . .

That's a bummer when that happens (uncertainty).

Maybe... get a little mirror and LED light... IDK??? LOL Ask him to bust his *** if he really wants to sell it to you and pull the damn thing out and get the #s like that.. HAHA

good advice from all. but i already bought the car. i dont mind even if it is 305 i just need to know for my restoration. to ease everyones mind i only paid 950 for a running and it passed inspection, firebird

Well thats good.. as long as you are happy... 305 and 350 parts are semi interchangable.. what do you need to restore on the engine?

There are numbers on the side of the block as well, the last 3 of the casting number. That will tell you as well, and usually they are easier to see.

The block definatley is the only way to tell if the current motor is a 350, however you can run the vin through the decoder here and see what was originally put in it.

I'd just tear a head off, but I LOVE wrenching more than most.

i really dont need to restore the engine i just want to add a tpi and tune it up. i need to know what size it is for the new chip ya know

where exactly would i find those numbers. i tried gettin in back with a light and a mirror but well i didnt see much

okay what you do is make sure cylinder #1 is at BDC pull the rockers off of cylinder #1 then jack the driverside way up into the air i mean way up and fill the cylinder with 50W oil put the plug back in and then jack up the passenger side and have a measuring can ready pull the plug and catch it all in the can turn the engine over to get as much oil as you can out then just do the math...

or get a flashlight and mirror /camera if you need to take a bagillion pics and start comparing

the block should have 5.0 or 5.7 stamped on it somewhere. Look around with a fashlight and maybe a mirror.

Best wishes finding it on the BACK of the block..try a mirror...that might work.

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