318 mismatch infos

[ValerianMagnum]

Ok ! Hi guys , i have 2x old LA's that im putting appart and 1x 5.2 magnum , i read that you magnums and La ( 318s ) bottom ends are interchangeable, 5.2s have a 9.2 compression and the old mid 70s La are close to 7.9 -8.0ishh , can i swap pistons too ? Im aware about the rest : heads / valvetrain and oil pans , but i was really curious about these 2x bottom ends , thanks !

 

[67Dart273]

I thought I knew that at least the rods are different (deck height?) and that the cranks are a different balance.

 

[273]

 

[junkyardhero]

if you change EVERYTHING over-- pistons, rods, crank, dampener then yes.

mixing and matching is a recipe for disaster. or at least needing expensive machine work.

anyway the problem lies in the rods-- different little end thicknesses, and pistons corresponding different pin bosses. and ultimately, weights, which would require a rebalance.

 

[volaredon]

Cranks are the same between LA and magnum.at least when talking about the 318

 

[ValerianMagnum]

if you change EVERYTHING over-- pistons, rods, crank, dampener then yes.

mixing and matching is a recipe for disaster. or at least needing expensive machine work.

anyway the problem lies in the rods-- different little end thicknesses, and pistons corresponding different pin bosses. and ultimately, weights, which would require a rebalance.

if you change EVERYTHING over-- pistons, rods, crank, dampener then yes.

mixing and matching is a recipe for disaster. or at least needing expensive machine work.

anyway the problem lies in the rods-- different little end thicknesses, and pistons corresponding different pin bosses. and ultimately, weights, which would require a rebalance.

Yes...since i have a couple of complete engines..i wanted to swap the best in the best block , i read a couple of years ago that you could swap the complete rotating of a magnum in a La...and i thinling about it or even just take pistons that have a better ring package , and they are internal engines..the 360s are more harder to get right

 

[ValerianMagnum]

Cranks are the same between LA and magnum.at least when talking about the 318

Yes exactly, but i was thinking about the rods and pistons too...

 

[junkyardhero]

to repeat: magnum rods are thinner on the piston end. you can't use magnum pistons on LA rods-- unless you want to do machine work to the rod (or piston). best to swap the whole assembly over.

that being said i would strongly recommend a rebalance if you're swapping any components piecemeal. the only work around there is to swap the entire reciprocating assembly wholesale.

 

[ValerianMagnum]

to repeat: magnum rods are thinner on the piston end. you can't use magnum pistons on LA rods-- unless you want to do machine work to the rod (or piston). best to swap the whole assembly over.

that being said i would strongly recommend a rebalance if you're swapping any components piecemeal. the only work around there is to swap the entire reciprocating assembly wholesale.

Yes sorry , i wasnt clear but yes its black or white...just wanted to be sure if could use the complete magnum stuff....without problems , damper and all in @ LA