Small Block vs Big Block in Charger cruiser purchase

[jaywalker]

Looking to buy a '71-'74 Charger in decent running condition and running into a decision problem. My preference would be a 383/400 setup, but seems like every car I find (other than being bought out from under me) is a 318 or 440.


Now, I really don't want a 440 because of insurance and MPG. Also scared the block will have been ragged out hard and just a gear shift away from blowing up. But on the flipside...is the 318 too anemic?


This won't be a strip/track car, just a Sunday Funday cruiser and occasional casual Fri drive to work which is 60miles round trip.
Goal: 0-60~ 8.5secs or 14.9qtr mile for on-ramp. Gas mileage in 12-15 range minimum.

Plan: if a 318, definitely 4bbl, intake, electronic ignition, headers installed and maybe head porting and a cam replacement down road. I know on paper that should push the block to 300HP. Keep tranny and gearing for hwy cruising. This will be in TX where sea level is about +500-700ft and biggest "hill" is a clover leaf overpass.
Will that be enough for a heavy BBody while not sacrificing gas mileage too much?

440 would be cool, but too many horror stories of 8mpg on hwy and worse in the city make me say "nope."

 

[Ron Ward]

Ummm.... Just food for thought. My insurance company NEVER asked me what engine was in the car, just what the VIN number was. Check with them to see what rates would be for your car with just the VIN number.... and then build the engine you want.

 

[Moparmatt72]

X2 I've never been asked engine size either. If that's the case I'm really screwed when I get to my next engine build for my 72 satellite lol

 

[dieseldazzle]

Put a small turbo on your small block and overdrive behind of it. Stay out of boost for good gas mileage and stay in boost for 14.9@105mph tire spinning fun!!!!!

 

[jaywalker]

After posting I just called insurance to see rates and you're right. They don't care. My company just wants an appraiser to give a cash value v appraisal value of vehicle which is replacement cost factored into policy minus a 200 deductible. So it looks like engine size won't play into hidden costs that way.

The question of performance still stands though; If a 318 can do it?
I know in high school when I inherited a '74 dart swinger 318 2bbl that, after a good tune up, that thing tree'd multiple rice burners and could hang with 90s model Mustang GTs and Camaro Zs from a stop light...not bad for a grandma's coupe. I am just concerned if it could do the same with a BBody Charger.

 

[Seventy]

Just start where you end up...

 

[Dennis H]

Big Block.

 

[WP29440SE]

its not like a stock 440 has 600 more horsepower over a stock 383 or 400 ...

 

[Homstead]

Once you've had Big Block there`s no going back! You get spoiled by the torque very quickly. Just my 2 cents......

 

[Archie340]

Once you've had Big Block there`s no going back! You get spoiled by the torque very quickly. Just my 2 cents......

Very true, I have two stock chargers - one a 383HP w/3. 55's and the other a rallye 340 w/3.23 gears. For around town I usually drive the big block car. The additional torque makes it a fun car to drive and gets the rather heavy B Body moving easily with good power throughout the rpm range. My 340 does best on the highway, pulls pretty good with some rpms and with the stock thermoquad gets half way decent mileage. If your really concerned about mileage a 340/360 might be a good compromise, but if you get a big block you won't want to let it go.

 

[Dibbons]

I believe the insurance companies don't ask about engine size because they determine that when we give them the VIN. They are set up to decode the VIN just like the rest of us.

 

[mopar 3 B]

In 73 we pulled the hemi from a 69 RR and instilled a twin turbo slant 6 the guys insurance dropped dramatically with almost identical hp and tourqe ratings. The engine swap was varifyed by the insurance company and they cared less about the engine add on's. The last I heard of the RR the slant was still in it and the hemi sold with the car. I have not figured out way we do not still have this insurance stupidity or have I just reached an age where it does not matter anymore.

 

[Burns69RT]

Do a 440, build it right. Put fitech efi on it and get 18 mpg hwy. and that's with 600hp.. Seen it done.

 

[Street fighter]

If you are going to build a 318 you might as well go to a 360, not much difference in gas mileage. I have had all four engines and I enjoy my 360 most, I have a 360 bored 30 over 10-to -1 flat top pistons rpm intake ,edelbrock heads,750 holley carb.with a mile crane cam,hooker headers and mufflers, 323 gears and a 2000 stall convertor with a tci trans.good power and not too bad on gas. if you adjust your kick down cable just right it will pull hard from 45mph to 75mph easy.If you want a 440 that have not been bored or misused I have a 440 block that came out of my 73 newyorker also a 400 block that came out of my 73 charger that now have the 360 listed. either way you go gas will be used.I have always said if you are worried about gas mileage you might want to get a rice burner..

 

[Bruzilla]

Here's what I've learned over 30+ years. You can start with whatever engine you like, but if you're driving a cruiser you're most likely going to end up with a 440 these days. You're going to take your car cruising and you're gonna get all kinds of compliments... until you get to the engine. You're going to hear "Oh, you just got a 318 in there huh. Bet you wish you had a 440!" or words to that effect a lot. It's like dating a super hot blonde who when she smiles looks like Margaret Thatcher.

What's worse is with the restoration business tanking more and more every day, there's less and less demand for smaller engines, so pretty much 50-75% of every dollar you put into a smaller engine, especially a 318, is gonna get thrown away when you do realize you've made a grave mistake and decide you really do want the Top Dog engine.

From an engineering perspective, the 318, actually any small block, is a great engine. But these aren't everyday general transportation drivers we're talking about. We want the emotional benefit as much as the engineering benefit and 440s meet that need the best.

 

[QQBlue1]

I have a 318 in my Charger and depending on the conditions, I get around 15mpg. I get 225 lbs of torque with the four barrel, headers and a mild cam and a 3.55 gear. It is a great cruiser, but after 20,000 miles on this set up I want more out of it.

If you go the 318 route, I'd advise that you do some good homework on the heads and cam combo to make your time worth it. Otherwise, I'd go with either a 360 or BB as a base and save your money for your preferred gear ratio in the back and then invest in the EFI as suggested by Burns69rt suggested.

 

[idrivemopar]

Here is a chart, factory numbers from Motor Manual for Dodge, with the 4 barrel options except 318

71
318 - 230hp
340 - 275hp
383 - 300hp
440 - 370hp

72
318 - 150hp
340 - 240hp
360 - 240hp
400 - 255hp
440 - 330hp

73
318 - 150hp
340 - 240hp
360 - 170hp
400 - 260hp
440 - 280hp

74
318 - 150hp
360 - 245hp
400 - 250hp
440 - 275hp

There is nothing wrong with a good small block, I love my 340, and its built up mildly, with 335 horsepower, much better than it was when stock, and it gets up and boogies! If you do small block, 340 or 360 good. I love the big blocks too, next project will be big block.

Hope this helps.

 

[HT413]

I'm building a 451, so you know where my personal opinion is. However, a 318 by today's standard is a BIG engine, so if you build it with today's technology such as a roller cam and more modern heads, (even a turbo or small supercharger) you can have a very powerful package that will be a heck of a lot of fun. However, the cost will be relatively close to a 'basic' 440 build (or even much more with boost). Also, I'd think a 440 car with some smart parts choices (3.23's, mild cam, quality converter) that is finely tuned with a smallish vac secondary carb would turn decent gas mileage WELL above single digits. So maybe that smallblock gets 18 mpg driven easy and the 440 gets 14? Is that really enough of a difference?

As with unique homes and pieces of art, just putting that small block into the car will hurt resale value but your biggest issue will be the dramatically reduced pool of potential buyers. Food for thought.

 

[Dennis H]

Big Block.

 

[PP1RT]

I would concentrate on getting the best quality car for the money. Whatever motor you end up with you can modify for your taste and needs. Its a big car. Its gonna take some power to make it move. Power takes fuel. Good luck.