Which SBM for the Mopar vehicle

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StreetSleeper

StreetSleeper

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(Am having trouble expressing the question, bare with me please)

When assessing a Mopar project


How do you decide what is sufficient?:

A body cars can be economical with 273/318’s and smaller, with enough acceleration to move in traffic as a daily driver, and with 340, 360 or stroked even faster. So anything seems to work with them, but what about when getting heavier?

But if you are starting with a clean slate rolling chassis

How much engine (torque & hp) would you want to have to safely drive in heavy traffic for:

Some of the B bodies (since size varies)

C bodies

FMJ bodies

Single cab truck -assuming potentially towing a vehicle once or twice

Or larger truck -(assuming potentially towing a vehicle once or twice)

Would you ever tow with a car?


Where I live there are SHORT ramps into a busy express way with semi’s driving 70-90 as you merge into traffic. And freeway crossings where semi’s are driving 60+ while you have to gauge, and sprint in front of them to cross the road.

How much engine size or <hp+torque> would you choose for those vehicles with a small block, and when would you guys switch to a larger engine?

I am not considering racing, just public driving including aggressive big city driving in traffic.

I realize there can be a multitude of purposes within daily driving or street, but create boundaries of what YOU would use any of those Mopar vehicles for.

I know this concept is a messy soup, but thanks anyways!! Your input (wisdom) is most appreciated !!
 
A well thought out and built 360 should have enough grunt for most applications short of a 3/4 ton truck that is used for heavy towing, or a C body. I would look at a 400 at least for those. Just my .02.

Edit: hp and torque in 300 plus range.
 
I can't even think of a mopar that didn't come stock from the factory with a 318 available.
 
StreetSleeper said:
(Am having trouble expressing the question, bare with me please)

When assessing a Mopar project


How do you decide what is sufficient?:

A body cars can be economical with 273/318’s and smaller, with enough acceleration to move in traffic as a daily driver, and with 340, 360 or stroked even faster. So anything seems to work with them, but what about when getting heavier?

But if you are starting with a clean slate rolling chassis

How much engine (torque & hp) would you want to have to safely drive in heavy traffic for:

Some of the B bodies (since size varies)

C bodies

FMJ bodies

Single cab truck -assuming potentially towing a vehicle once or twice

Or larger truck -(assuming potentially towing a vehicle once or twice)

Would you ever tow with a car?


Where I live there are SHORT ramps into a busy express way with semi’s driving 70-90 as you merge into traffic. And freeway crossings where semi’s are driving 60+ while you have to gauge, and sprint in front of them to cross the road.

How much engine size or <hp+torque> would you choose for those vehicles with a small block, and when would you guys switch to a larger engine?

I am not considering racing, just public driving including aggressive big city driving in traffic.

I realize there can be a multitude of purposes within daily driving or street, but create boundaries of what YOU would use any of those Mopar vehicles for.

I know this concept is a messy soup, but thanks anyways!! Your input (wisdom) is most appreciated !!
Click to expand...
If your talking how much engine performance (anything above the 20-50 hp needed to move the car) is needed for normal driving, I'd say look at modern family cars there performance is basically what an average consumer demands, seems to be a 14-15 second car. When people are pepping up an old car but say performance ain't overly important, I assume they want a 15 ish second car.

I guess that would make a performance car to be a 13-10 or less second car.
 
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Now needed engine size for a given hp/tq. For a normal driving street only focus car, I'd say rpm (powerband) is gonna be the biggest factor, so whatever cid that can make the needed peak hp around 4500-5000 rpms for a 14-15 second car. Probably whatever the driving weight of the car is knock an zero off and your in the ballpark eg.. 3600 lbs = 360 cid.
 
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StreetSleeper said:
How much engine (torque & hp) would you want to have to safely drive in heavy traffic for:

Some of the B bodies (since size varies)
Click to expand...
318
StreetSleeper said:
C bodies
Click to expand...
360
StreetSleeper said:
FMJ bodies
Click to expand...
No different than an A body- anything from a slant to a 360.
StreetSleeper said:
Single cab truck -assuming potentially towing a vehicle once or twice

Or larger truck -(assuming potentially towing a vehicle once or twice)
Click to expand...
318/360. Single cabs were available with slant and V 6s, so a smallblock is no issue, even with "towing once or twice".
StreetSleeper said:
Would you ever tow with a car?
Click to expand...
Hell yes. I pull a 16' camper, a 14' boat, and a 10' utility trailer with my '66 Dart wagon. I wouldn't hesitate one minute, as long as the vehicle is set up properly to tow. I've got a custom receiver hitch, load equalizers and an electric brake controller- all common stuff you'd need for towing with any car.
StreetSleeper said:
Where I live there are SHORT ramps into a busy express way with semi’s driving 70-90 as you merge into traffic. And freeway crossings where semi’s are driving 60+ while you have to gauge, and sprint in front of them to cross the road.

How much engine size or <hp+torque> would you choose for those vehicles with a small block, and when would you guys switch to a larger engine?
Click to expand...
The stuff you're talking about here isn't so much a matter of engine size, you're better off worrying about rear end gearing. Bigger, heavier cars could navigate traffic just fine with a 273 if it's geared right and running good. Something around a 3.23/3.55 and a good running small block (even a slanty) of any size will be just fine for navigating daily traffic and accelerating up onramps and through intersections. Just remember that as your gears go up (numerically) you'll gain torque, but you'll decrease your mileage and increase RPMs at highway speeds.
I think you're overthinking this a bit, you'll be fine in any ABFMJ with any smallblock, in a C body or truck I would gravitate to a 360; a big block if doing frequent towing, but that's not what you asked.
 
For what you describe, I'd say a stock 318 or 360 magnum depending on how important fuel mileage is to you. 318 for mpg, 360 for a little more oomph.
 
StreetSleeper said:
(Am having trouble expressing the question, bare with me please)

When assessing a Mopar project


How do you decide what is sufficient?:

A body cars can be economical with 273/318’s and smaller, with enough acceleration to move in traffic as a daily driver, and with 340, 360 or stroked even faster. So anything seems to work with them, but what about when getting heavier?

But if you are starting with a clean slate rolling chassis

How much engine (torque & hp) would you want to have to safely drive in heavy traffic for:

Some of the B bodies (since size varies)

C bodies

FMJ bodies

Single cab truck -assuming potentially towing a vehicle once or twice

Or larger truck -(assuming potentially towing a vehicle once or twice)

Would you ever tow with a car?


Where I live there are SHORT ramps into a busy express way with semi’s driving 70-90 as you merge into traffic. And freeway crossings where semi’s are driving 60+ while you have to gauge, and sprint in front of them to cross the road.

How much engine size or <hp+torque> would you choose for those vehicles with a small block, and when would you guys switch to a larger engine?

I am not considering racing, just public driving including aggressive big city driving in traffic.

I realize there can be a multitude of purposes within daily driving or street, but create boundaries of what YOU would use any of those Mopar vehicles for.

I know this concept is a messy soup, but thanks anyways!! Your input (wisdom) is most appreciated !!
Click to expand...
You have quite a wide range of vehicles, that could require require different powerbands and levels.

For a Daily Commuter car.

A car say < 3,200lbs can easily get up to speed quick enough to be a daily driver with 175<200hp.

I would like 200 < 275hp for 3,200 < 3,800lbs.

300 < 350hp 3,800 < 4,000lbs.

My 93' Dakota with 230hp was more than adequate to move its 3,800lbs in stock form for daily driving. Loved to cruise at 85<110mph with 3.55 gears.

Towing is more about tow vehicles weight, GCWR, Engine, gearing and hitch rating which determines towing capacity.

For people like me we are always looking for more.
 
You would flat be AMAZED at how, uh, "sufficient" a decent running, bone stock 273 TWO bbl is for power. I actually had one in my 70 RR !!! ??? !!! (whut?) THAT IS RIGHT!!! I swapped a 340 into my formerly known is '70 440-6 RR in about ?73? during the gas crunch. AFTER I got out of the Navy, came home, some time later, I decided to sell the RR (biggest mistake I EVER made!!) so I yanked the 360 out of the FJ-40 Landcruiser and prepared to stick the 340--in the RR--into the Landcruise. BUT I NEEDED A 3rd "wheel." So I bought a well worn 273 from a guy for FIFTY BUCKS and just dumped it right into the RR. One thing "not" stock were the headers already on the car. THIS WAS NOT a Commando!!!

You are talking about a RR, weighed over 3800, with the big 'ol Dana 60 3.54 and 18 spline 4 speed, and that little bitty 273. My friends and I were equally amazed. It was completely driveable.
 
ANOTHER example. Friend of mine in the Navy had a ?68--69 ? Charger with a stock 318 automatic, probably 3.23 gears. I was AMAZED at the torque and "pick up" that car had.
 
My own 67........Before I stupidly tore it down to paint, I for a short time had a low miles 318, about a ?? 71--72 model, put a small cam in there, 4bbl intake and various carb/ efi. That thing was AMAZINGLY fun to drive. I did have headers, duals. Stock, low compression, regular gas
 
A /6 is more than capable of powering a daily driver, questions is if you want more power it's up to you to decide how much more. Pick a car that has the performance your looking for and it's 0-60 1/8 1/4 ability and figure how much power your car needs to do similar and at what rpm will tell you around how much cid you'll at least need.

A very mild street engine with decent performance be like 0.7-0.8 hp per cid.
 
StreetSleeper said:
(Am having trouble expressing the question, bare with me please)

When assessing a Mopar project


How do you decide what is sufficient?:

A body cars can be economical with 273/318’s and smaller, with enough acceleration to move in traffic as a daily driver, and with 340, 360 or stroked even faster. So anything seems to work with them, but what about when getting heavier?

But if you are starting with a clean slate rolling chassis

How much engine (torque & hp) would you want to have to safely drive in heavy traffic for:

Some of the B bodies (since size varies)

C bodies

FMJ bodies

Single cab truck -assuming potentially towing a vehicle once or twice

Or larger truck -(assuming potentially towing a vehicle once or twice)

Would you ever tow with a car?


Where I live there are SHORT ramps into a busy express way with semi’s driving 70-90 as you merge into traffic. And freeway crossings where semi’s are driving 60+ while you have to gauge, and sprint in front of them to cross the road.

How much engine size or <hp+torque> would you choose for those vehicles with a small block, and when would you guys switch to a larger engine?

I am not considering racing, just public driving including aggressive big city driving in traffic.

I realize there can be a multitude of purposes within daily driving or street, but create boundaries of what YOU would use any of those Mopar vehicles for.

I know this concept is a messy soup, but thanks anyways!! Your input (wisdom) is most appreciated !!
Click to expand...
All of this might come down to 2 simple things...

1. What you have to work with/ availability?

2. How much money do you want to spend?

Once you start changing the setup from stock/ was available... things get expensive.

For example: Switching from a perfectly adequate 318 with factory trans. To a current Efi hemi with a ZF trans or T56 manual.$$$
 
I've owned over 400 vehicles since I was 13. The absolute most fun I have ever had was when I started messin with slant sixes. That's no joke. Thanks, Bruce! (RIP)
 
Whatever vehicle/motor you end up with, make sure it can stop as well as it can go. I see it all the time, leaving some room between you and the one in front when some jerk in a Kia decides to jump in front of you for whatever reason
 
Means you called it "messy soup".... I recommend moving away from the rat race of short ramps and 90 mph bumper to bumper traffic and land in a small town and open roads. Then, you can drive a '84 2.2 Reliant and not worry about it. And let life begin ... lol
 
StreetSleeper said:
(Am having trouble expressing the question, bare with me please)

When assessing a Mopar project


How do you decide what is sufficient?:

A body cars can be economical with 273/318’s and smaller, with enough acceleration to move in traffic as a daily driver, and with 340, 360 or stroked even faster. So anything seems to work with them, but what about when getting heavier?

But if you are starting with a clean slate rolling chassis

How much engine (torque & hp) would you want to have to safely drive in heavy traffic for:

Some of the B bodies (since size varies)

C bodies

FMJ bodies

Single cab truck -assuming potentially towing a vehicle once or twice

Or larger truck -(assuming potentially towing a vehicle once or twice)

Would you ever tow with a car?


Where I live there are SHORT ramps into a busy express way with semi’s driving 70-90 as you merge into traffic. And freeway crossings where semi’s are driving 60+ while you have to gauge, and sprint in front of them to cross the road.

How much engine size or <hp+torque> would you choose for those vehicles with a small block, and when would you guys switch to a larger engine?

I am not considering racing, just public driving including aggressive big city driving in traffic.

I realize there can be a multitude of purposes within daily driving or street, but create boundaries of what YOU would use any of those Mopar vehicles for.

I know this concept is a messy soup, but thanks anyways!! Your input (wisdom) is most appreciated !!
Click to expand...
My wife's corolla 4 banger gets around just fine in traffic.

Based on this evidence, I'd say you really have to have a 408 or larger, just to ensure your safety. Hope this helps!
 
With an overdrive transmission and the right gearing even a stock 318 could keep up with traffic in anything but the heaviest truck or C-body. That's how modern cars with 2.x 4-bangers make it work, my wife's 2013 Camry with the 2.5L engine goes 0-60 in 8 seconds thanks to having a 6-speed trans. It's when you go to pass someone at 70+ mph you feel the lack of power.
 
MopaR&D said:
With an overdrive transmission and the right gearing even a stock 318 could keep up with traffic in anything but the heaviest truck or C-body. That's how modern cars with 2.x 4-bangers make it work, my wife's 2013 Camry with the 2.5L engine goes 0-60 in 8 seconds thanks to having a 6-speed trans. It's when you go to pass someone at 70+ mph you feel the lack of power.
Click to expand...
And when you have to come to a sudden stop you realize the brakes could use some help, too.
 
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