The Pushrod Hotrod- A Dying Breed

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I heard and read the stated reason Chevy has avoided OHC tech in their V-8's is to keep a low hood line in the Corvette.
After all, what good would it be to have a GM look like a Cobra or a Viper? The new motors sound smooth, but boy are those coil packs ugly!
 
You will be hard pressed to see pushrod motors go by the wayside. Especially considering Chrysler and Chevy have been making over 400 HP in their small blocks for several years now. The engine expense is considerably less than ford dohc motors. When Chrysler and Chevy get into their "hot rod" set up, they are smashing out over 700 hp from production pushrod motors. They will be around for a good long while.
 
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Had a subscription to mm&ff for almost 15 years. Canceled because of their material. Hardly any "old" articles. All the new ohc stuff just got boring to me. I still pick one. Up at the magazine rack
 
It is getting harder and harder (read that as more expensive) to get/keep a pushrod engine within ever tightening emission/fuel economy standards. The OHC architecture is so much more efficient in this matter that it is just nuts. That is the main reason Ford went this route years ago. They could see the writing on the wall. The pushrod engine is almost at the limits of efficiency. I am sure direct injection will keep it viable for a few more years, but at some point GM/Chrysler are going to have to go the OHC route on all of the engines.
 
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I would beg to differ on that emission/fuel economy statement. Dodge gets better fuel mileage in their 5.7 pushrod than Ford gets in its DOHC 5.0...... Ford has to sell fuel mileage based on the Ecoboost.
And how do they do that? Oh yea, they cut out cylinders when cruising. Ford does not do that .........yet. A Dodge running on all 8 cylinders does not get as good a fuel economy as the 5.0 it is simple physics. When all 8 cylinders are banging away and you have to feed almost 50 cid more, and the amount of power required to operate the pushrod set up is more than the OHC, well, it is just a losing proposition.
 
And how do they do that? Oh yea, they cut out cylinders when cruising. Ford does not do that .........yet. A Dodge running on all 8 cylinders does not get as good a fuel economy as the 5.0 it is simple physics. When all 8 cylinders are banging away and you have to feed almost 50 cid more, and the amount of power required to operate the pushrod set up is more than the OHC, well, it is just a losing proposition.

Uhhhh......I'd venture to say that they shut off the cylinders in an attempt to give you the best of both worlds. Who needs all eight cylinders banging away when the objective is 30MPG regardless of the size of the V8.
 
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Uhhhh......I'd venture to say that they shut off the cylinders in an attempt to give you the best of both worlds. Who needs all eight cylinders banging away when the objective is 30MPG regardless of the size of the V8.
I agree, I was just pointing out how they were getting better fuel economy with the pushrod motor and larger displacement. I was making the comparison to show that if it ran on all 8 like the 5.0 Coyote does, then it would not be a contest. When/if Ford ever does this cylinder cut-off thing (I hope not) then it will be game over.
 
Northstar was OHC variable cylinder... so its been done...and as stated GM cited corvette hood clearance for the push rod direction...

lets face it GM and Chryslers are not shooting stars these days and that has to be a factor in staying with that tech, the vast majority of the automotive world has moved on.

My 5.9 4wd Durango mpg paid for Crawford Ranch... It was cr*p all the way around....
 
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Meh, both of my '05 Rams got 20-21 mpg and they didn't have MDS. Both 4wd, one with 3.55's and the other with 3.92's
Man they must have really improved their economy. I had a 318 Durango that was lucky to get 15-16 hwy and it averaged about 12. That thing sucked and was in the shop 4 times the first year. I hated that f'ing thing and traded it with about 15000 miles on it. Took a killing just to get rid of it.
 
Not bad. Just got back from Philly in my 14 Hemi Citadel Durango 4wd and @ 70 I got 22-23 with 6 and a 1/2 people and some luggage. I love that Hemi!
 
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