i dont know if this is the right place for this question but i jus bought a 84 camaro z28 for 400$. i was told that a 350 was put in it. but after i pulled the motor out to clean it up and work on it i noticed is has 5.0L on the back of the block so i know its a 305. but its a centerbolt 305 which they didnt have til 87 and this camaro is a 84. i know its not the stock motor but idk wat it is. is a centerbolt 305 still a LG4? what heads are on centerbolt 305s? it has a holley street dominator intake, holley 650 carb with 1" spacer, 160 thermostat, and heddman longtube hedders. should this motor run pretty good once i get it in the car again? and what cam does a centerbolt 305 have? is it a roller? any help would be greatly appreciated. THANKS

 

Centerbolt valve covers only define the heads, and even then only the era. Get the casting #'s from underneath the valve covers. That's the only way to know what heads they are. Could be LG4, could be LB9, could be LO3, could even be LO5 or L98.

Ditto the block. You saw the "5.0L", now get the casting number which is right in the same area. Since at least the heads have been replaced, there's no knowing what block it is without the casting #.

After getting all that, you still don't know what cam it has, because casting #'s don't tell you that. The VIN/SN stamped on the right front corner pad (in front of the head) may give a little more information about that.

 

, the only way to know is get the numbers. after you get the casting #'s, you can go to Mortec.com and you can cross reference both the block and heads and find out what they came from individually. finding out exactly what cam it has can be difficult. like five7kid stated, you can check on the corner pad (pass. side just in front of the head above the water pump) to see what it should have, maybe. another way to check is take the intake off and see whats in the lifter valley. if its a roller cam, it will have some form of lifter retainers, either stock "dog-bone" style with a spider spring to hold them in place, or a retrofit style setup with button and collar style retainers (basically a flat piece of metal that clips to the lifters to stop rotation). if it doesnt have any of that, then its most likely a flat tappet cam of some kind.

maybe someone got nutsy and did a 335 stroker on a 5.0 liter block. thatd be a sweet lil engine. good luck with it, get some pics if you can! we all like pictures

 

i took the drivers side valve cover off of the centerbolt head 305 and off of a spare perimiter bolt head 305 i had laying in my garage out of an 86 silverado. behind the second rocker on each head there was a vin.

centerbolt head-1402187
perimiter bolt head-100450?? i couldnt make out the last two numbers

on the back drivers side of the blocks they both have 5.0L then on the back passenger side of the block they both have vins.

centerbolt motor-14093627
perimiter bolt motor-14088551

 

Casting #, actually.


14102187, perhaps? Swirlports, originally a TBI engine.

Something isn't right there. 1004xxxx isn't a production casting #.

Truck or passenger car TBI engine.

Fits the '86 claim.

 

swirlport heads so does that mean that the centerbolt motor was originally an LO3? that he put a 4barrel intake and carb on? is that good? would it be better to build the perimiter bolt 305? i have the same parts for it-aluminum intake, carb, thermostat, headers, summit hei. or would it pretty much be the same?

 

Yes, it most likely was an LO3.

If you're building a low-RPM, stock factory cam, economy, torquey engine, the swirlports are the way to go. In general, it's safe to say a 650 carb would be too big for a swirlport 305.

If you're building something for a little more spunk, you want something else. I'd need to understand exactly what those heads are before I could say ya or nay on the perimeter bolt heads.

If you have the intake off of the engine, you should be able to tell whether or not it has roller lifters.