I have a 89 iroc conv. that is labeled a 305. My question is can you tell a 305 from a 350 without decoding it I have always thought that a 305 balancer is wider than a 350 and it is hallow.The reason that I am conserned is thatthe balancer is thin and solid like a 350 when Ibought the car and it did not run well it does just not very well my thought is that someone has installed a 350 and didn't change the computer. It's symptoms are as follows it starts ok and idles decent but when you try to throttle it, it hesitates and if you try to hard to get it to accelerate it pops though the intake. It don,t act like a timing issue but I could be wrong if someone could give alittle input on any of my issues I would greatly appreciate it.

 

if it is a 87up engine it will have 5.0G or 5.7G cast into the back of the block by the distributor. that is the easiest way to tell. some aftermarket companies use the same balancer for the 5.0 that they use for the 5.7 (all balancers are interchangeable except the 400 because it is externally balanced) . it is possible that the engine is a 5.0 but has a aftermarket partshouse balancer.but if it pops back through the intake that sounds like a timing issue and not a fuel issue.

 

I agree. I would check the timing first. There should be some numbers at the front of the engine, near the pas side head. I know you dont want to decode, but I think thats the only way.

 

here ya go, http://www.mortec.com/castnum.htm

 

I don't have a problem with decoding the engine I just thought the balancer was a eay and quick way to get a idea of the cubic inches. Ok to time a tpi I assume you need to do more thatn just hook up a timing light don't you have to bypass the computer so that it wont advance kinda like pulling the vacuum line off a vacuum advance dist.. I maybe wrong but about that so if any has detailed info on timeing a tpi engine I would greatly appreciatte it.

 

Holy crap! Someone swapped a 350TBI into mine... I wouldve never known.. That just made my day!