i just bought a chevy sb and the casting number is 3970010, it says on mortec that it could be a 69 302, 69 327, or 69-80 350. how can i be for sure what it is? please help.

 

It's almost certainly a 350.

 

By the crank.

Get the crank casting or forging #, and that will tell the tale.

In the "real world" though, I'll tell you right now, odds are WAY less than 1% that it's anything other than a 350. Nobody in his right mind builds 327s any more, since they cost the same as a 350 but give 23 less, and parts are far les common; and the 302 costs WAY WAY more, but gives 48 less than a 350, and is only of value for someone recreating a "numbers matching" Z28.

 

and they also said it has 202 heads, how can i tell that?
also if it is a 350, how can i tell what year 350 it is? i dont see a date on it.

 

They probably mean it has 2.02" intake valves. You can figure out the date from the codes on the block, nut there's no reason to care.

 

and would i be better off sticking to my stock 305 or put my tpi stuff on this 350? or should i just switch to carb?

 

There's no such thing.

However, there IS such a thing as heads that have 2.02" intake valves installed in them.

To tell that, you just measure the diameter of the intake valve.

If the head castings are crap, or even if they're good ones, just graunching the larger valves into them accomplishes exactly NOTHING except for putting stars in the eyes of inexperienced buyers, and lightening their wallets a little extra. Since the valves themselves are the same price as the standard 1.94" ones, to the penny, but the seller can pry ALOT more money out of the uninformed buyers he is likely to encounter, an AMAZING number of junk heads that needed their valves replaced anyway, have had that done to them.

Get the head casting number. That, and the porting that has been done to them, is more important than the valve size.

The date is cast right into the block right next to the casting #. Post it and I can tell you the exact date it was cast. Beyond that, which is meaningless enough as it is, whatever happened to it by being rebuilt has COMPLETELY destroyed any likeness to whatever it was when it was new; so knowing what its original HP "rating" was, or even what kind of car it was originally in, is altogether worthless now. It tells NOTHING about what the motor now is.

 

ya but should i switch my TPI stuff over to this 350 or change to carb with this 350?

 

That depends on alot of things.

Like, what 350 it really is; as determined by what pistons are in it and what heads are on it. And, what your goals for the car are, and your budget, and how complete the car is now. FI can get REAL expensive REAL fast, besides being a REAL hassle, if certain things (fuel pump, ECM, wiring) are missing or damaged.

I'm not a big fan myself of yanking out FI and sticking in a carb, or vice-versa. I think it's usually better to work with what you've got, if it's workable. But your situation might be different from mine. So, more info would be needed to evaluate that.

 

the car is in running and driving condition but has a 87 305 TPI engine in it, i wanted to get more hp and torque so i got this motor, the motor was rebuilt and im sure it has the regular style pistons in it, he told me it has 2.02 heads on it, and that it needs a new bearing, thats all i know, other than that, i got everything i should need to convert the engine over im sure, what do you think?

 

Still need to know what the 350 actually IS; head castings, and pistons, and what porting has been done (if any), and what cam is in it (part # only please, no "¾ race" or "RV" or "mild" or "lopey" or "Comp" with nothing further). As well as, what new bearing it supposedly needs, and why. With that, maybe we could make a good technical guess as to whether it would work well with TPI or not. But that doesn't address the PRACTICAL concerns, like emissions inspection, fuel consumption, your own level of tools and skills, and so forth.