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3.1/3.4 vs 3.8 GM engines

I have sometimes wondered why the 3.8 liter v6 seems to enjoy a better reputation compared to GM's 3.1/3.4 liter offerings. On paper, the smaller motors would appear to be a more rational design, due to the

60 degree bore spacing allowing for proper balancing without the need for split crank pins, balance shafts, special motor mounts, etc.

I know about the lower intake gasket issues on these 3.1/3.4 motors. Are there any other reasons to prefer the "v8 with 2 cylinders missing" design of the 90 degree 3.8?? (other than bigger displacement, of course)

Regards, Al.

Reply to
Al Haunts
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60 degree GM v-6's use split crank pins. They all use "special" mounts....mostly fluid filled ones at certain locations.

With a balance shaft, the 90 degree engines are very smooth.

Ian

Reply to
shiden_kai

Reply to
Silver Surfer

That refers to how the rod journals are arranged. Having offset rod journals between main journals. Two rods even though side by side their journals are not in line with each other.

Reply to
noname

OK. Thanks. I get the picture now.

Reply to
Silver Surfer

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