318cui in a 71 dart

[jayyzf]

Anyone. Know what the compression on a 1964 318cui engine stock should be. Trying to find one to replace a slant 6 in a 1971 dart. Got a possible used motor that has 115-119. Just wondering.

 

[doug 371]

that's a poly isn't it

 

[krazykuda]

that's a poly isn't it

The 65 & 66 poly had 9.0 compression, I think that the 64 should be the same... #-o

 

[2 Darts]

The 65 & 66 poly had 9.0 compression, I think that the 64 should be the same... #-o

Right, 9.0:1 according to the Standard Catalog of Chrysler. I've found inaccuracies in the book as they show the early LA 318 to have a 9.0:1 CR when everything else reads 9.2:1

The 1964 318 is a polyshperic engine, not an LA. The LA 318 came out with the 67 MY. The 273 A-body exhaust manifolds bolt right up to the LA 318, not so the poly 318. This means you're on your own when it comes to getting exhaust gas out from under the hood especially on the drivers side of the car. The poly is also heavier than the LA, so a change of torsion bars is highly recommended.