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440 6 pack or Gen III hemi

Impatient '71

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Hi everyone. New member to the forum, but been reading threads for years. Anyways, I'm looking at building a 71 gtx or roadrunner and am trying to get opinions on engine choice. I'm currently debating either a Gen III hemi or building a 440-6 pack with the kit from FB throttle bodies. The goal is reliability as I plan to make this car my daily driver. Besides cost what else should I consider. I want to run an air grabber hood with air conditioning. I also prefer an automatic due to bay area traffic.
 
Welcome to the group. I think your choice of engine depends on your driving desires. If you want a car with low end torque that can melt the tires, 440-6. If you want to go around corners, with upper end power, then I'd go new Hemi. It'll take weight off the front as well and aid in better handling. Of course, you can use aluminum goodies on the 440 and reduce weight as well
 
Welcome to the site. Personally if you're running fuel injection I don't see the point of a six pack. I single computer controlled throttle body will work just as well. Running a big block and an automatic your overdrive options are very limited so you'll need to take that into account. A Gen III is alot of fabrication to make it work. It's a tough decision but I'd probably still go with the 440 over the Gen III Hemi.
 
If you are starting with a GTX or Road Runner, I would try to keep it as close to stock as possible. If it is a 318 Satellite, then follow your heart.
Personally, with the high priced junk gas we have these days (and getting worse), I would bite the bullet and go Gen III since you said you want a daily driver. It is a lot of expense and work up front but the benefits give you the best of both worlds IMO. I went that route with my Charger and with the 6.1 / 5 speed auto and 3.23 gears, my car runs 1700 rpm @ 70 mph delivering 22 miles per gallon and will still knock down a mid 12 second quarter mile at 105. As soon as I get the cruise control working, I will be ready to deal with the Chebby guys on the Power Tour.
 
Welcome.

FiTech has a 3x2 EFI setup good to 600 hp, they say. Would be a cool, modern take on the 440-6. Don't know anyone that has used it, though.

If you are looking to have an OD auto trans - Gear Vendors is an option, kind of pricey. The Chrysler A-518 and 46RE require floor pan and suspension rework in order to fit; pricy. There is also the A41 (Keisler/Silver Sport Transmissions) that gets you a 4-speed auto. Its a GM 4L60E with a engineered adapter kit. Very little mods needed, they say. You could do the same with the GM 700R4 or 200-4R if you don't want an electronically controlled trans.

There are many thoughts on Mopar "purity", it's your car, do what makes you happy. I happen to have a 700R4 that is going into my Super Bee with 3.91 rear gears. It's a compromise to get some form of gas mileage and reduced wear when highway driving.

Good luck, most of all, have fun.
 
My 1st choice would be the 440 6bbl F&B EFI
I like the old school BB look
most all of that can fit under a org. style fresh air N96 Airgrabber
so it can maintain a old school appeal

the Gen III hemi is a dead giveaway when the hood open
otherwise who would ever know

the Gen III hemi is a popular choice too

I think both can work very well, depends on how you build them
& what behind them
I think the modern Hemi would be considerably better on mileage
especially with a newer o/d trans
of course depending on what mods you do to it
all of that cost can be a factor, I guess you know that already

it's your car
don't worry about what someone else thinks
"build it how you want it"
if you want to cut it up & make a racecar out of it
than more power to ya'
you want to do a resto-mod or pro-touring same deal
go for it, don't look back
you want it to look bone stock on the outside,
but modern drivetrain stuff under it
than by all means go for it
 
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FiTech has a 3x2 EFI setup good to 600 hp, they say. Would be a cool, modern take on the 440-6. Don't know anyone that has used it, though.

Link? I can't see it on their website... Is it maybe from another supplier?
 
Thanks for the replies. My basic goal is reliability, while at the same time keeping the exterior and interior of the car looking like a car from 1971. The plan is to restore/ modify the interior to original with the floor shift and center console as I just love the look and can't seem to see any functionality issues with this setup, although having never owned one don't know if I'm missing something like I can't figure out if there are cupholders on the center console. Along with this I'll be adding an air grabber hood, as I love the look and have yet to find one that came with this option. I had not really thought about the gas mileage or highway RPM issues, so I'll have to look into the transmission possibilities. Will any of the overdrive transmissions setups work with the factory floor shift and center console?
 
Oh.. the latest dilemma in building an old Mopar for more than sitting next to it at car shows!
An Air Grabber setup for a 71 is going to be VERY expensive. I don't know your budget but I've read of complete setups with the hood going for $3000.
I have been tempted to pull my 440 and install a 392/6.4 Hemi. The power is great, they run smooth and get decent mileage. They have less torque but do come on strong in the middle and top end. The stock 3G Hemi heads outflow almost every aftermarket Big Block head so these engines really come alive at mid range and up.
I can't justify it though since I do not drive the car 15,000 miles a year to make the expense balance out.
That may be different for you.
A 6 Barrel (Plymouth's brand name for the triple carburetor setup) arrangement can make decent mpgs but a ThermoQuad 4 barrel can too for a fraction of the price. It does not look as cool but they do run well. The Mopar 383-440 engines are easy to rebuild, fit your car using factory parts and will run a long time. There are no factory overdrive transmission options but as stated, there are options there. Overdrive really helps with distance driving. We have all become accustomed to cruising at 75 mph with the engine loafing at 2000 rpms or less. My 70 Charger with 3.55 gears runs 3200 rpms at 70 mph! I like the sound for a little while but it does wear on you after awhile.
 
IMG_20170311_164240474.jpg

If you want to hear cool, when you open the hood, here is the answer.
 
Hi everyone. New member to the forum, but been reading threads for years. Anyways, I'm looking at building a 71 gtx or roadrunner and am trying to get opinions on engine choice. I'm currently debating either a Gen III hemi or building a 440-6 pack with the kit from FB throttle bodies. The goal is reliability as I plan to make this car my daily driver. Besides cost what else should I consider. I want to run an air grabber hood with air conditioning. I also prefer an automatic due to bay area traffic.
I have a friend with a complete 440 six pack .040 over with 4 speed that lost oil pressure. He wants to sell PM me if your interested and I can give you the details. ( located in Colorado FYI)
Thanks,Joe
 
HERE IS MY 6 PACK motor in my 65 Belvedere.
It is a 1969 6 Pack motor with INDY Aluminum Heads, TTI ceramic headers and MSD Ignition.
Block is correctly date coded 10/2/69. This motor has the Edelbrock manufactured ALUMINUM intake manifold for the 3 2 Barrel setup.

3.jpg 48.jpg
 
If you can keep the VVT stuff, there is really no comparing a 6.4 Hemi to an RB engine. Stock for stock is a 440-6 at 375 gross hp. 6.4 Hemi? 485 NET hp.
Add headers, tune, better cam and pound for pound technology kills any Vietnam War era bullit.
 
440 6bbl is 390HP/490ft/lbs torque.
For me, I like old school. Screwdrivers to tune instead of laptops.
I have yet to hear ANY modern day muscle car sound as good, especially at idle w/my cutouts open and my 292°/.509 Purple Stripe cam loping along,

or WOT sucking air through 3 Holley 2bbl carbs.
I just added the Innovate Motorsports dual wideband O2 system so I can data log and see both sides of the exhaust A/F ratio data in real time. I think that is going to be a great tuning tool.
I "get it" re: modern engines, and after suffering through the late 70s, and 80s with crap "performance engines" from the factory, I am amazed at what modern performance engines do.
I go to lot of car shows. I promise I get a lot more "oohs and ahhs" with my open hood than any Gen 3 car.
20180923_160037.jpg

I have 6 2bbls to tune between our 2 cars
20180921_160413.jpg

Amazing performance for a heavy Jeep, but I put him on the trailer 3-0:
 
I chose the gen 3 hemi/Tremec 6-speed because I plan to drive my car.
Old school muscle would be my first choise if I only planned to cruise around Town and doing some burnouts here and there.
But I plan to take longer roadtrips and for that I need reliabillity and some form of fuel economy without making any compromise on performance.
I Think the gen 3 hemi is a great platform and if you ad better exhaust and a performace cam it gets even better.
And considering that premium fuel in Sweden is more than 6 USD/gallon its a no brainer.

file-26.jpeg
 
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