Will a 87-95 tbi intake work on an 1986 tune port block (came out of a 305ci firebird) without slotting any holes. I bought a 1989 intake today casting # 14102182 Rebuilt the 1986 305 installed it in an 1989 silverado the original 89 305 froze and busted the block we towed it from and apartment complex as abandoned vehicle have no history of the vehicle. Rebuilt the 1986 305 and installed it in the Silverado. The original intake off the 1989 was cracked and bought a replacement from craigslist and found out it was slotted. Now I'm hearing that some of the the slotted intakes leak and are differnt angles mating on the flat surfaces (slight but differnt). Ran perfect in the beginning but then began to not idle and run rough. Heard from two people this a typical characteristic of slotted hole intakes at first they run fine then heat up and don't run fine. Haven't ran a air leak intake test yet because I went to Pull a Part and got a GM 1989 Silverado TBI intake today just because I don't trust the slotted one. Changed the map sensor, idle air, and am rebuilding the intake when I change the intake. Anybody seen or heard of this.