Ok folks, here is the skinny, I have read a plethora of posts regarding 305 to 350 swaps but never had all of my questions answered, so I am writing to answer some of those questions folks may have.
? One or two piece rear main seal You will have to find the right flywheel relative to your current bell housing arrangement, automotive manual clutches work just fine at a fraction fo the price)
I went from 1994 1-piece rear main seal 305 to a 1972 2 bolt 350 two piece rear main seal, I would have rather gone 1-piece 350 with roller cam but I bought my 2-piece block for $55 std bore, also had to purchase a 168 tooth manual clutch flywheel since the bolt pattern gage is different from 1 piece to 2 piece. (Flywheel is same year as block it worked out ok for my app). Be aware of how many teeth you currently have I recommend you stay with what you have unless you want to swap your bell housing. For ex. If you currently have 153 tooth and have to go with 168, you will have to purchase a new bell housing and possibly a new coupler. For my application everything bolted up with no problem, also be aware of what kind of coupler you have, this will make a big difference. Remember auto manual flywheels will work.
? Camshaft I used a Comp extreme marine, do your research if you want to use a truck grind make sure it?s comparable to a marine grind.
? Flat tappet camshaft be sure to break it in properly even if you have break in oil, you worked too hard to get it right so don?t slip up and fry your cam right off the bat!
? Piston to cylinder clearance I used Keith Black pistons that specify a loose clearance for marine app. so that is what I did. Very similar to personal watercraft engine building specs. Don?t forget top ring file for KB pistons. ? BUY AN ALIGNMENT TOOL- If you think you can use your input shaft your probably going to be wrong, it may slide in smooth but the alignment can still be off due to tolerances between input shaft and coupler. Spend the extra bucks for the tool. This is a huge project don?t clip yourself!
There is a lot more to write about but I wanted to address the gaps I had in my research. If you are thinking about doing this kind of swap DO IT! You will learn so much and the best thing about it is you can pass it along to the next fella. Please ask questions I will be glad to answer them. Bye the way my total project cost is just below $2500 you can do much better in cost but I wanted the custom build and maximum hp for the coin. Plus I get to say I built the engine.
Cheers!
? One or two piece rear main seal You will have to find the right flywheel relative to your current bell housing arrangement, automotive manual clutches work just fine at a fraction fo the price)
I went from 1994 1-piece rear main seal 305 to a 1972 2 bolt 350 two piece rear main seal, I would have rather gone 1-piece 350 with roller cam but I bought my 2-piece block for $55 std bore, also had to purchase a 168 tooth manual clutch flywheel since the bolt pattern gage is different from 1 piece to 2 piece. (Flywheel is same year as block it worked out ok for my app). Be aware of how many teeth you currently have I recommend you stay with what you have unless you want to swap your bell housing. For ex. If you currently have 153 tooth and have to go with 168, you will have to purchase a new bell housing and possibly a new coupler. For my application everything bolted up with no problem, also be aware of what kind of coupler you have, this will make a big difference. Remember auto manual flywheels will work.
? Camshaft I used a Comp extreme marine, do your research if you want to use a truck grind make sure it?s comparable to a marine grind.
? Flat tappet camshaft be sure to break it in properly even if you have break in oil, you worked too hard to get it right so don?t slip up and fry your cam right off the bat!
? Piston to cylinder clearance I used Keith Black pistons that specify a loose clearance for marine app. so that is what I did. Very similar to personal watercraft engine building specs. Don?t forget top ring file for KB pistons. ? BUY AN ALIGNMENT TOOL- If you think you can use your input shaft your probably going to be wrong, it may slide in smooth but the alignment can still be off due to tolerances between input shaft and coupler. Spend the extra bucks for the tool. This is a huge project don?t clip yourself!
There is a lot more to write about but I wanted to address the gaps I had in my research. If you are thinking about doing this kind of swap DO IT! You will learn so much and the best thing about it is you can pass it along to the next fella. Please ask questions I will be glad to answer them. Bye the way my total project cost is just below $2500 you can do much better in cost but I wanted the custom build and maximum hp for the coin. Plus I get to say I built the engine.
Cheers!
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