Thread: V6 3.4 or 4.3 How can you tell

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I was alomost not going to post to this.Haft heartedly I am addressing the statement that 4.3's are only a cut down 350.The fact is the spacing of the bores,the split journals,and the offset of the rods makes it very different than 350's.

Originally Posted by 1gary

I was alomost not going to post to this.Haft heartedly I am addressing the statement that 4.3's are only a cut down 350.The fact is the spacing of the bores,the split journals,and the offset of the rods makes it very different than 350's.

Yes, they're different internally, but the o.p. was looking for visual cues to identify a 4.3 and those are very much like a 350 V8. By the way, the bore centers of a 90º Chevy V6 are the same as the small block V8 engines. They addressed the split crank throw issue with narrowed/larger rod journals. The 3.8 Buick V6 did eventually get a "spread" bore spacing in the 3800 Series to eliminate the off center rods, but that's a horse of a different color.

Bob

Originally Posted by 1gary

I was alomost not going to post to this.Haft heartedly I am addressing the statement that 4.3's are only a cut down 350.The fact is the spacing of the bores,the split journals,and the offset of the rods makes it very different than 350's.

same bore spacing, same hd bolt pattern (use 3/4 of a 350 torque plate when boring) same piston, same rod length (use v-8 rod by narrowing big end), timing chain/sprokets, rocker arms, push rods, lifters, water pump, oil pump.......

[shrug]
Russ

Guys actually not.I dealt with bore spacing and offset rods when I had to try to straighten the design out buying a Chevy Bowtie block Busch Grand National 4.3.Back then I had it in a Chevette as a drag car.It is a common pin on center rod engine.Cost a bundle to build.