i have a 69 400 stage 1 motor and there's a good chance that it's seized up forever. How close would a 68 GS 400 short block motor be for a donor ?? I would like to use the heads from the 69 motor on the 68 if necessary? Thanks
From what I understand it should be very similar, I think the stage 1 400s had some valve unshielding done at the top of cylinder bore. What makes you think it's locked up forever?
68/69 had standard small valves , basically just cam carb and distributor and it was a stage To put the stage valves in a 400 you would need to open the bore up but wouldn't gain much IMO
The 69 stage 1 motor sat in the car out in Montana? For 35 years. When I went to remove the engine oil, the bottom of the oil pan came with it. The 1" of rust on the bottom of the oil pan and the white pistons lead me to believe it's not fixable. I would probably use just the block and the crank from the 68 400 motor and put the bigger valves stage 1 heads On it. Should I post engine numbers here? I have them...o
If it is the original motor to the car I might let a shop look at and see if it's fixable or not. Even if it had to go some weird size over, today you can get any piston one would want or need made. I would guess as long as the block isn't cracking or holes in, it's more than likely fixable.........just depends on the cost and money willing and needed to repair it
I have it in a formidable engine shop waiting in line now. Mine was next They should give me an answer here soon. The OEM motor does need a carb, distributor , oil pan and a few other things that I was missing... I guess I need to be a bit more optimistic,
Once again, 68/69 stage 1's didn't have bigger valves That was the "big deal" when the 455 came out in 70 bigger bore for bigger valves
Everything is fixable. Corroded pistons and stuck rings are no big deal, it just adds up shop time. An entire industry unheard of is dedicated to fixing irreplaceable castings.
Yes, if it is the original block to your GS,it can be pulled apart ,saved and restored with all new bore Sleeves. Good as new
I agree with keeping the original block as long as the rest of the car is going to be kept numbers matching. However, one point to ponder is that when decking a block during normal machining procedures, often the code and serial number can be machined completely off. Then you have a numbers matching block that can't be verified.
