I kinda agree with the above. Your 305 was never designed to be a performance engine, not without doing a bit of reworking anyway. Your money would be better spent, or saved, somewhere else. I would just do what needs doing.

 

can i run a turbo350 tranny on a 400

 

Yep. Don't forget the 400 is an external balance engine and uses a different flex plate from the other small blocks.

 

oh ok....so i can get that but i have to change a few parts or a can get a 350 and leave it...hmmm 350 with 350 HP and tq or a 400 hard decision

 

With a 350 engine bolted in to replace the 305 with a T350 trans, it's plug and play with the same flexplate and all.
The 400 engine just needs a different flexplate and harmonic balancer because it's externaly balanced but other than that it's a small block and bolts right in just like a 305 or 350.
The 305 will make a good anchor or overgrown paperweight once you have a 350/400 in there.

 

ya i agree....the problem i have now with my car is the harmonic balancer...on the original timing chain cover it had a peice on their to make the balancer TDC but my new chrome one does have it ....how can i make the harmonic balance TDC with out that peice