Ralph Cramden wrote:
FishOnOne wrote:
I wonder if this engine will be based on gm's current small block or will it be an all new engine
I suspect still based on the small block, and will remain a cast iron block. Its fairly easy to increase the bore, stroke, or both to get to 6.6. You would only need to beef up the casting to get the bore out to 4.25 from the current 4.0 with the 6.0, and you would almost have the 6.6 displacement right there at the current stroke, but I would assume a combination of both bore and stroke. Thats without even getting to the heads. GM performance already has blocks that can be taken out to that range.
Then add in direct injection over the current SFI used in the 6.0.
Of course some version of cylinder deactivation is in the works FWIW.
Maybe they'll have some method of deactivation for the deactivation.
I was looking ahead to the 2019 / 2020 HD body redesign, but no first year engine is going to be bought here be it GM, Ford, Ram, or anyone else. Had one of the first GM LM7 5.3's in 2000 with the common piston /wrist pin slap at cold startup. 230,000 miles when sold in 2012 and still on the road 18 years later with no problems, but that knock when cold for a minute or two every morning was enough to drive you crazy. Almost enough to send you over the cliff when they tell you its "normal" which it apparently was.
I agree..I don't believe they are going to design a whole new engine for a 6.6L.
The LS platform is already available in 7.0L in cars, and the iron block 6.0 is stout, if a bit long in tooth. It seems to do well in comparison tests even though it has less horsepower and torque than both the Dodge 6.4 and the Ford 6.2.
Boost the displacement a little, update a few other things. Boom, 400hp/450ftlbs torque.
The whole big block/small block thing is kind of out the window these days. The 6.8 V10 is just a "Small Block" 5.4 with 2 more cylinders.
The 6.4 Hemi is just...a 6.4 Hemi with some changes to fit the HD application better. The same with Fords 6.2. The bottoms ends on todays "small blocks" are much stronger the they use to be.
