I had a 305 tbi in my 1992 rs but it has 3 dead cylinders so I found a smoking deal on I think around 1980 new rebuilt 305 long block that is carb intake setup. I was looking at some forms and they said I can drill the center holes carefully at a angle to put on my old tbi intake can anyone give me some input on this Thanks.

 

Its more of slotting the holes & grinding that area so the bolts sit flat. You might have to use larger washers too.
I think you might have to change the distributor gear over, the 92 engine should have a bronze gear to match a factory roller cam. The older engine probably has a regular flat tappet cam, so it needs a steel gear.

 

Thank You I still have about another week or so till the intake install if anyone else has any more input let me know

 

you will also need a different flexplate for the two piece rear seal crank, and a blocker plate for the fuel pump port.

 

also if it doesn't come with valve covers the older heads need perimeter bolt covers.

 

Your original TBI heads will bolt right up to the 1980 block (and they have the same 58cc chamber size as the 1980 vintage heads). Of course, if the reason you have 3 dead cylinders is because your TBI heads are shot..... that swap wouldn't help much. Used stock LO3 heads in good condition can be found for about zero bucks, fortunately, for someone willing to pick them up and haul them away!

Yes, you can modify the intake manifold but it will always be a bit of a "hack job" since it's not just the angle of the holes it's also the angle of the pad that the bolt heads seat against.

 

many that have done carb swaps on the 87 to 1992 engines including me have slooted the center bolt holes on the intakes and had them work fine. they will seal great. no worries.

 

word. i've done it as well.

 

Yes, but you went the other way. Carb intake onto TBI heads. He would be doing the opposite.

 

put a carb intake on it with an adaptor if he has to. if he is using tbi heads it wont be a problem. either way it is easy to make it all work.