GM’s new 6.6-liter small-block V-8 could be a treat for hot rodders


Hot rodders, rejoice—General Motors is bringing back the venerable 400-cubic inch V-8. That’s great news for anyone who lives by the rule there’s no replacement for displacement.

This is a companion discussion topic for the original entry at https://www.hagerty.com/articles-videos/articles/2019/02/11/new-gas-v8-for-silverado-hd


Let’s just hope they make it available in the Silverado Regular Cab with Standard bed. Don’t understand why they won’t put anything larger than the 5.3 ltr in it. If they don’t will have to look at Ford or Ram.


More antiquated pushrod engine engine technology. Why not 4-valve DOHC? with turbo capability? This 6.6 is just more old-school stuff. GM continues to be a declining company, unlike the innovative company they were from the 1920’s to the 1970’s, culminating in controlling almost 60% of the American car market.


Ford which used OHC engines in their trucks for years just came out with a pushrod gasoline engine for their trucks before GM announced theirs. I don’t know why but there must be a reason. Trucks don’t need high revving engines could be one reason. Low end torque is preferred. Maybe these pushrod engines produce more. Serviceability is a key factor also and DOHC engines are quite wide on top and more complicated. Being a mechanic I cringe when I look under the hood of some trucks because of all that is packed under there.
One more reason might be a new basis for a NASCAR engine where OHC is not allowed.


All I see is another pig on gas new V-8 engine.


Yeah, me too, I mean my blown LS 1 only gets 32 mpg at 70 on the highway, and 22 mpg around town. Don’t believe it, ask my wife the CPA, who didn’t either, until she did the actual math, and the DIC ( driver info center), was right on the money. Shut her right up. I’ll bet this LS based engine can be in the high 20’s or low 30’s as well, in the right car with the right gears. Know your crap before you open your trap dude.


GM always makes a strong power train and the aftermarket always comes up with a nice kick in the pants programmer! The problem is the rust and thin metal used in the frames. Years ago it was so thick you could let it rust with no worries. Now they fold in half within 10 years of rust belt weather.


Similar to GM, Ford, the Big-Three OHC purveyor, just announced a brand new pushrod 7.3-Liter V8 for their 2020 Super Duty. The engineers at both companies have determined that a large-displacement, OHV engine will provide the best reliability, power-to-weight, torque delivery, and fuel economy for their given RPM operating range.

Like it or not, pushrod engines do carry distinct advantages over their OHC (and forced induction) counterparts. There’s a reason why GM’s LS and LT engines are as successful as they are.


I have a small block 400 in my trusted out 1979 Silverado Suburban. Last of the forged steel crankshafts in the engine. I finally parked it after the roof rack rusted off. I keep,it in case my 80 Vette L82 ever blows up.