I Live Here
Joined: Jan 2003
Posts: 16,123
Grand Haven, MI
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Its really too bad that more wasn't done with this engine. No real aftermarket, never put in cars, etc. In my quest for a quick, cool-sounding and extremely efficient V8 for my 70 Challenger i want to daily drive i kept coming back to this one. Its small, its light and being a DOHC it will sound wicked with some dedicated pipes, make very good power and kill anything else in efficiency.
because the 5.7 is lighter, physically smaller, more efficient (with MDS), more powerful AND cheaper to manufacture....
sounds like you need a 5.7 in your chally. my '11 charger is a beast power wise (published times are ~13.7 in the quarter, ~5.2 0-60, in a 4250lb car) while getting 22-23mpg in mixed driving over the 8k miles I've had the car...
I dont think the hemi is more efficient... as a design. With the MDS sure... but i've always thought that was a really stupid idea. Its a cop-out. Rather than actually design a truly modern and efficient engine, they just find ways to use less gas in an inefficient engine? Why not just build a better engine? Ford did. Its just hokey from start to finish i think. I dont want a V8 in my car that becomes a 6 or 4cyl... i want a V8! With a better design i CAN have my cake and eat it too.
Just my opinion. Not a fan.
If they made (and i'm sure you wont hear this coming from anyone else...) a smaller hemi... say around 5.0L... then maybe (though still without the MDS). But sheer size has its drawbacks, and in MY case i just dont need a big engine. The car is light. A 318 could be fast in this car... Hence my recent obsession with the Ford mod engine.
the hemi, without MDS is quite efficent--stick challys don't have it, and still get 26+MPG on the highway.
the hemi is a thoroghly modern and efficient engine in cyl head design, and it boasts some advantages over in-line valve heads like the LSx and the 4.6L SOHC heads-- being a hemi (more accurately a modified pent roof), the valve moves AWAY from the cyl bore as it opens, reducing valve shrouding significantly. having this arrangement also creates a much better short side radius geometry.
it's not a cop-out, it's simple physics. you need a certain amount of torque and HP for steady state cruising, most likely 30-50HP depending on speed and aerodynamics. an engine's volumetric efficiency is higher the closer you are to WOT (less vacuum=less pumping losses). the 90 degree V motor has natural balancing if it's a 2cyl, 4cyl, or 8cyl. so it makes sense to deactivate half the cyls (and keep the air column trapped by not opening the valves, eliminating pumping losses on those cyls) to increase fuel economy. the cyls' deactivate round-robin style, so it's not like the same cyls are shut off for 100 miles in a trip. and on my 2011, going into and out of MDS is seamless. if it wasn't for the "eco" light in the dash, you couldn't tell with stock exhaust. it reacts and refires the cyls in fractions of a second. THAT is having your cake and eating it, too. there is no natural engine balance on a 60 degree V6 where you could deactivate cyls, that's why it's not done--there's have to be some external means to cancel vibration....I'm surprised car companies haven't looked at a 90 degree V4, with cyl deactivation, honestly. most likely it's a packaging issue, as it would be a lot harder to package in a transverse, FWD arrangement.
and there is a certain elegance of design with a pushrod OHV V engine that you lose once you go to OHC. and just because it's a OHV cam-in-vee motor doesn't mean you can't do variable valve timing, or even multivalve heads...
1) fewer moving parts--1-3 less cams (SOHC or DOHC) and a MUCH simpler cam drive arrangement
2) shorter distance between crank to cam drive, means less potential variance in cam drive timing and wear
2) much smaller physically--having the cam in the vee instead of on top of the heads makes for a much more compact design (compare the PHYSICAL size of a 7L LS7 motor and a 4.6L or 5L ford DOHC motor)
bigger displacement=more torque. again, it's that dang physics....give me a 5.7L and the torque it provides when I want and need it, and a 2.85L when I don't....
1976 Spinnaker White Plymouth Duster, /6 A833OD
1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!***
2011 Toxic Orange Dodge Charger R/T
2017 Grand Cherokee Overland
2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)
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