68 Dart Project

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winter

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I'm starting my Dart GT project and have two questions that I need help with. The planning is already months deep, with the expectation to complete at least a year away.(probably longer)
The first problem is a much needed "BARE" 360 block. So is it a waste of time searching for the LA 360 (one which is seasoned and can take a rebuild is rare or extinct)... Or just find a 5.9L ? Remember I only need the block, and i can still buy a new 5.9L bare block.
Are they basically the same block with only slight upgrades in the newer 5.9L. (basically its going to be a 408ci. stroker when finished)
The second questions, will I have to do tranny tunnel work to fit a SB 727 under the Dart floor. Remember its a 68.
 
If you want to run a hydraulic roller than find a magnum block.

If you aren’t running a hydraulic roller, buy whichever is cheapest.
 
There are still early 70’s blocks out there. The late 80’s early 90’s blocks will have roller cams. Depends on how much horsepower you are looking for. High horsepower is best with a x or r block. A 727 came stock in many 68 darts and you should have no problem there.
 
ch1ll said:
There are still early 70’s blocks out there. The late 80’s early 90’s blocks will have roller cams. Depends on how much horsepower you are looking for. High horsepower is best with a x or r block. A 727 came stock in many 68 darts and you should have no problem there.
Click to expand...
Too bad OP is so far away . I know of a 89 transitional motor that can be bought for $300.
 
I would consider that a good price. I have an 89 also but haven’t pulled it apart yet, 308 heads as well.
 
ch1ll said:
There are still early 70’s blocks out there. The late 80’s early 90’s blocks will have roller cams. Depends on how much horsepower you are looking for. High horsepower is best with a x or r block. A 727 came stock in many 68 darts and you should have no problem there.
Click to expand...
Again , thanks for passing this knowledge on!
 
winter said:
I'm starting my Dart GT project and have two questions that I need help with. The planning is already months deep, with the expectation to complete at least a year away.(probably longer)
The first problem is a much needed "BARE" 360 block. So is it a waste of time searching for the LA 360 (one which is seasoned and can take a rebuild is rare or extinct)... Or just find a 5.9L ? Remember I only need the block, and i can still buy a new 5.9L bare block.
Are they basically the same block with only slight upgrades in the newer 5.9L. (basically its going to be a 408ci. stroker when finished)
The second questions, will I have to do tranny tunnel work to fit a SB 727 under the Dart floor. Remember its a 68.
Click to expand...
No issues on the 727, they were factory installed on '68s.
La/Magnum block choice will depend on what type of heads you intend to run. If you're going to run LA style heads, be aware that other than the first couple years of production, Magnum blocks were not drilled for rocker shaft oiling of LA heads. It's not a deal killer, but it will affect how you approach the rest of your build- you will need to account for the oiling by either:
Drilling the missing passage into the Magnum block.
Going to an "oil through" type lifter/pushrod/rocker system.
Supplying pressurized oil via added lines to the rocker assembly.
 
ch1ll said:
There are still early 70’s blocks out there. The late 80’s early 90’s blocks will have roller cams. Depends on how much horsepower you are looking for. High horsepower is best with a x or r block. A 727 came stock in many 68 darts and you should have no problem there.
Click to expand...
My 69 Dart has a 727 in it, there are no fitment issues to be had.
 
ch1ll said:
There are still early 70’s blocks out there. The late 80’s early 90’s blocks will have roller cams. Depends on how much horsepower you are looking for. High horsepower is best with a x or r block. A 727 came stock in many 68 darts and you should have no problem there.
Click to expand...

Professor Fate said:
No issues on the 727, they were factory installed on '68s.
La/Magnum block choice will depend on what type of heads you intend to run. If you're going to run LA style heads, be aware that other than the first couple years of production, Magnum blocks were not drilled for rocker shaft oiling of LA heads. It's not a deal killer, but it will affect how you approach the rest of your build- you will need to account for the oiling by either:
Drilling the missing passage into the Magnum block.
Going to an "oil through" type lifter/pushrod/rocker system.
Supplying pressurized oil via added lines to the rocker assembly.
Click to expand...
yeah I've done alot of homework on the Light A block and 5.9l,but I knew that I still didnt have all the answers,so it was time to reach out to the mopar nation. I knew about the oil drilling to a 5.9l decided this was not the way to go. So starts the search for the elusive LA. Plans for trick flow heads with the rocker rail is a must have, pedistal rockers are weaker, so the heads and valve train are a no brainer. Now that you guys have sorted the differences in the two blocks, I gotta find a old pick up truck in the bone yard. There must be one out there that wasnt eaten by the crusher. hey thanks again for the info !
 
I'm not trying to trying to reinvent the wheel, thats a job for engineers. They've got years of schooling and experience. Like some of you, my experience comes from trial by fire and even trial by error (things dont always work out). We all know the value of a dollar, (half the battle is the Almighty dollar) and I cant afford to waste it, So planning and due diligence seems to be the best route.
We all love our cars and trucks, High, shiny, or loud, its all good !
 
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