All new GM 4.3L v6

[SCNTN]

The new Silverado/Sierra had a rather lukewarm reception, but in all the talk about the new styling, features, etc, not many people bothered to report on the all new 4.3L v6. Myself, along with practically every other S-series pickup owner out there, would love to see a more efficient powerplant for these trucks. The typical engine swap is to a Vortec 350 or LS-based v8. And while these motors increase power significantly, it is at the expense of extra weight and reduced FE (albeit marginal).

Enter the new 4.3L v6. Similar to the its historical cast-iron cousin, it is derived from a small-block GM v8 with two cylinders removed. However, the new motor is an all-aluminum, direct injection, variable valve timing V6 with active fuel management (displacement on demand) that turns the motor into a V4 on closed loop.

So now we have an all-new, lightweight, efficient, and powerful V6 from GM. Complete specifications have not yet been released, but estimates are around 260HP/300TQ and 25MPG in a full-size truck. And it should retrofit nicely in DaGnoma. About darn time!!

[nbleak21]

Wow! Now that is an impressive advancement! I'd love to have that in a locost!!!

[nemo]

I thought active fuel management was the right foot. (just couldn't resist)

[SCNTN]

Originally Posted by nbleak21

Wow! Now that is an impressive advancement! I'd love to have that in a locost!!!

Yep. Now if only they'd get rid of those pushrods!

[nbleak21]

Yes, DOHC would be nice but then they wouldn't fit in a locost!

[darcane]

Originally Posted by SCNTN

Yep. Now if only they'd get rid of those pushrods!

What's wrong with pushrods? GM has been getting great performance (power AND economy) out of their V8 engines with pushrods in a much more compact packge. Try comparing the Corvette's hood profile with the Mustang's and you will see one big advantage of not moving to DOHC.

[SCNTN]

Originally Posted by darcane

What's wrong with pushrods? GM has been getting great performance (power AND economy) out of their V8 engines with pushrods in a much more compact packge. Try comparing the Corvette's hood profile with the Mustang's and you will see one big advantage of not moving to DOHC.

I agree. I was being partly facetious. The LS1 in our TA has no problems pushing the car to 30mpg highway and 13 seconds in the quarter mile. OHC would be a slight boost to efficiency, but much harder to package.