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cajunfj40 · 07-11-2018, 06:33 PM

Unfortunately, I think it boils down to "Corvettes always have more horsepower than Camaros", at least in the consumer market.

If you take a look at the GM Two-Mode Hybrid system from 2008-??, the powertrain was quite a bit more capable than what it was constrained to.

The 2ML70 transmission was, roughly speaking, a 4L80E with two Remy HVH-250 cores in it. Those cores can do 80hp/147lb-ft continuous and 110hp/240lb-ft peak each at 350V - more with higher cooling fluid flow and voltage. Add that to the 332hp/367lb-ft 6.0L V8 it has, and you should have a blistering 672hp/847lb-ft available on full-combined-power takeoff, with at least 160hp/294lb-ft available in all-electric mode - enough to drive a modest load at freeway speeds.

As delivered and tested, you got a lower payload and a lower tow rating than the conventional 6.2L gas-only version, it accelerated slower, and electric-only was only available up to 32mph flat, 10mph uphill towing. As redpoint5 noted, GM only claimed a net 379hp - lower than the big 6.2 V8.

My guess is, much like how they substituted a constricted intake manifold on the V8 in the Camaro so it performed worse than the *identical* engine in the much pricier Corvette, they intentionally detuned the hybrid so it didn't beat the big V8. That also allowed them to go with a smaller battery pack, to keep the cost down. Have to keep the profit margins in line, so they mostly built them as fully optioned high-end vehicles. So they got some good ad copy from "Hybrid!" and "20mpg truck!", got some EPA fleet fuel economy benefits, and got to test out a bigger full hybrid system. I never really heard anything "bad" about them - unlike the variable displacement tech of the same era - and the 4x4 Tahoe Hybrids still go for over $10K on the used market.

Since then, we've been seeing steady improvements in power and payload ratings in fullsize trucks - but mpg has been relatively constant, or slightly improving, with a few "ringer" high-mpg offerings on stripped-down 2WD models. Engine sizes have also been dropping, without a loss in power or payload. So efficiency gains are still being made - at least per EPA tests. As fusion210 notes, there are mild hybrid options on most consumer trucks, either now or soon, and auto start/stop has been steadily improving.

I think we'll continue to see steady incremental improvement, and the manufacturers pretty much all have the tech available to spin up a plug-in hybrid relatively quickly if the market opens up for it. It will still need to "not beat the big engine" and not lose any profit margin, though.

07-11-2018, 06:33 PM	#18 (permalink)
cajunfj40 Lurking Eco-wall-o-texter Join Date: Dec 2015 Location: MPLS, MN area Posts: 128 Thanks: 0 Thanked 65 Times in 45 Posts	Why? Marketing and profit margins. Unfortunately, I think it boils down to "Corvettes always have more horsepower than Camaros", at least in the consumer market. If you take a look at the GM Two-Mode Hybrid system from 2008-??, the powertrain was quite a bit more capable than what it was constrained to. The 2ML70 transmission was, roughly speaking, a 4L80E with two Remy HVH-250 cores in it. Those cores can do 80hp/147lb-ft continuous and 110hp/240lb-ft peak each at 350V - more with higher cooling fluid flow and voltage. Add that to the 332hp/367lb-ft 6.0L V8 it has, and you should have a blistering 672hp/847lb-ft available on full-combined-power takeoff, with at least 160hp/294lb-ft available in all-electric mode - enough to drive a modest load at freeway speeds. As delivered and tested, you got a lower payload and a lower tow rating than the conventional 6.2L gas-only version, it accelerated slower, and electric-only was only available up to 32mph flat, 10mph uphill towing. As redpoint5 noted, GM only claimed a net 379hp - lower than the big 6.2 V8. My guess is, much like how they substituted a constricted intake manifold on the V8 in the Camaro so it performed worse than the identical engine in the much pricier Corvette, they intentionally detuned the hybrid so it didn't beat the big V8. That also allowed them to go with a smaller battery pack, to keep the cost down. Have to keep the profit margins in line, so they mostly built them as fully optioned high-end vehicles. So they got some good ad copy from "Hybrid!" and "20mpg truck!", got some EPA fleet fuel economy benefits, and got to test out a bigger full hybrid system. I never really heard anything "bad" about them - unlike the variable displacement tech of the same era - and the 4x4 Tahoe Hybrids still go for over $10K on the used market. Since then, we've been seeing steady improvements in power and payload ratings in fullsize trucks - but mpg has been relatively constant, or slightly improving, with a few "ringer" high-mpg offerings on stripped-down 2WD models. Engine sizes have also been dropping, without a loss in power or payload. So efficiency gains are still being made - at least per EPA tests. As fusion210 notes, there are mild hybrid options on most consumer trucks, either now or soon, and auto start/stop has been steadily improving. I think we'll continue to see steady incremental improvement, and the manufacturers pretty much all have the tech available to spin up a plug-in hybrid relatively quickly if the market opens up for it. It will still need to "not beat the big engine" and not lose any profit margin, though.