Better Torque From A 318

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Didn't think it would of been a problem asking people here for their thoughts on the subject.
I gave you my thoughts. Like I said earlier:

Looks like Chad doesn't have a problem maintaining homogeneity even @ 350 FPS when others might........
Do gases have issues turning corners like liquids entrained in a column of air? Go think about that for a while.
 
By who, not by me. Nor my friends either. All my cars were great highway mpg for what they were. 170 around 30 mpg, 273 around 25 mpg, 340 about 20 mpg, 383 about 18 mpg. All trucks stink for mpg, too much frontal area and the tailgate acts as a parachute besides. Try driving with the tailgate down, instant +2 mpg.
Unloaded my last dodge truck long ago and I replaced it with a Colorado.
 
By who, not by me. Nor my friends either. All my cars were great highway mpg for what they were. 170 around 30 mpg, 273 around 25 mpg, 340 about 20 mpg, 383 about 18 mpg. All trucks stink for mpg, too much frontal area and the tailgate acts as a parachute besides. Try driving with the tailgate down, instant +2 mpg.
The 225 in my duster got fair mileage. Some people have luck with a mopar getting good mileage. Mine never really did. I've known alot of people over the years that had a 318 in both cars and trucks and the mileage isn't there.
 
I gave you my thoughts. Like I said earlier:


Do gases have issues turning corners like liquids entrained in a column of air? Go think about that for a while.
Others gave their thoughts, you gave me questions with obvious answers and acting like it's gonna lead to some insightful light bulb moment, I'm fine with having a normal conversion but I don't want to play your bread trail question game. Just cause I've disagreed with you on things doesn't mean I think your not a knowledgeable person.
 
The 225 in my duster got fair mileage. Some people have luck with a mopar getting good mileage. Mine never really did. I've known alot of people over the years that had a 318 in both cars and trucks and the mileage isn't there.
I've never noticed much difference in older cars, but I'm 99% in town driving.
 
The 225 in my duster got fair mileage. Some people have luck with a mopar getting good mileage. Mine never really did. I've known alot of people over the years that had a 318 in both cars and trucks and the mileage isn't there.
i get a lil over 20 mpg in my D150 /6 od833 truck, something my 84 chevy silverado 350 th350 could never do, lucky to get 12 mpg! 85 diplomat 318 904 got bout same as my /6, 76 charger with 360 and 727 bout 12 to 14 mpg, 79 roadrunner with E58 360 727 with factory high stall got 15 mpg if you stayed outta it! 71 cuda hot 318 with J heads 904 if drove easy got 16 to 18 mpg! 71 duster 340 X block bore 4.080 X heads LD340 intake holley 750 .508 cam hemi 833 with 3:91s turning N 50s got better smiles to the gallon than miles!!!
 
Hi! I have been reading this with interest as I have recently bought another Aussie 1973 Valiant Charger 770 with 318 auto, A/C and Steer with 90 thousand KLMS on it (56k miles)This car is absolutely imaculate and the paint is about 90% original and mint! The 318 has a 4 barrel manifold and carby on it but I recently bought a 500 AVS2 for it for a bit more low speed response.
I do not wish to turn this car into a hot rod as I have another 74 charger with 410,5 speed that has about 550hp and runs low elevens.
What I want out of this car is a reliable cruiser with decent fuel economy but with a fair bit of low speed throttle response.
Recently my brother and I went to a car show up the coast doing a round trip of about 400klms and they both got about 21mpg. Yes the 410 with a 3.91 diff and big roller cam used exactly the same amount of fuel as the 318. This means the 410 is much more efficient than the std 318.
This is what I propose to do! The 318 is a 1972 dated engine as our cars had V8s purchased by chrysler Aust in batches usually a year before the build date of the car. This 318 does not have any pollution control as our pollution laws did not take place for a few years later. I think I will pocket port the bowls on the heads and maybe add 360 size intake valves and get a really good 5 angle valve job done and shave the head about .040 to increase the comp. I dont mind spending the money as I paid seventy grand for this car so am looking to put a roller cam and lifters in it but probably only about a 360 type cam as I want a good idle and power from idle but do not need it to rev to the moon.
As it has the std peashooter single exhaust on it I will probably put a single large diameter (2 1/2) free flowing exhaust instead of a twin system . A racer called Peter Brock always used to say on our 308 Holden engines back in the day that a large free flowing single exhaust usually makes more street power than dual exhausts on his 308 engines.
I am looking for your thoughts on a good roller cam profile for this combo?
 
My Duster with a 318 that was 9.4-1 comp, Edelbrock heads and intake, NO whiplash cam, ran 11.70s 1/4 mile, it had to make around 300hp i figure.

Convertor was a 3800, gears 4.30. I drove it to the track and drove home, car shows, grocery store, very street friendly car. 318s run good. the car went 1.62 sixty foot

Tell us about it, sounds interesting.

Can't wait to see the info for this mid 12 second 318.

ask and ye shall receive.

people out here acting like mid 12's from a 318 is witchcraft or you gotta make a deal with the devil. converter and gears will easily push a 318 into the 12's

i have a 69 barracuda, full curb weight. 318/727 stock stall w/ 3.23's the motor is an honest 9.5:1 with a 3/4 race cam topped with a afb and it clicks off 13 flat at 100mph. 318 will run has a van with, you guessed it, a 318 that also runs 13's. why would mid 12's be such a stretch?
 
people out here acting like mid 12's from a 318 is witchcraft or you gotta make a deal with the devil. converter and gears will easily push a 318 into the 12's
This^^^

Go study other brands and see how many people are doing that and more with similar cubic inches.
 
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Hi! I have been reading this with interest as I have recently bought another Aussie 1973 Valiant Charger 770 with 318 auto, A/C and Steer with 90 thousand KLMS on it (56k miles)This car is absolutely imaculate and the paint is about 90% original and mint! The 318 has a 4 barrel manifold and carby on it but I recently bought a 500 AVS2 for it for a bit more low speed response.
I do not wish to turn this car into a hot rod as I have another 74 charger with 410,5 speed that has about 550hp and runs low elevens.
What I want out of this car is a reliable cruiser with decent fuel economy but with a fair bit of low speed throttle response.
Recently my brother and I went to a car show up the coast doing a round trip of about 400klms and they both got about 21mpg. Yes the 410 with a 3.91 diff and big roller cam used exactly the same amount of fuel as the 318. This means the 410 is much more efficient than the std 318.
This is what I propose to do! The 318 is a 1972 dated engine as our cars had V8s purchased by chrysler Aust in batches usually a year before the build date of the car. This 318 does not have any pollution control as our pollution laws did not take place for a few years later. I think I will pocket port the bowls on the heads and maybe add 360 size intake valves and get a really good 5 angle valve job done and shave the head about .040 to increase the comp. I dont mind spending the money as I paid seventy grand for this car so am looking to put a roller cam and lifters in it but probably only about a 360 type cam as I want a good idle and power from idle but do not need it to rev to the moon.
As it has the std peashooter single exhaust on it I will probably put a single large diameter (2 1/2) free flowing exhaust instead of a twin system . A racer called Peter Brock always used to say on our 308 Holden engines back in the day that a large free flowing single exhaust usually makes more street power than dual exhausts on his 308 engines.
I am looking for your thoughts on a good roller cam profile for this combo?
Speak to George Rallis he did the heads on the teen that runs mid 12's. He can tell you all about it.
 
ask and ye shall receive.

people out here acting like mid 12's from a 318 is witchcraft or you gotta make a deal with the devil. converter and gears will easily push a 318 into the 12's

i have a 69 barracuda, full curb weight. 318/727 stock stall w/ 3.23's the motor is an honest 9.5:1 with a 3/4 race cam topped with a afb and it clicks off 13 flat at 100mph. 318 will run has a van with, you guessed it, a 318 that also runs 13's. why would mid 12's be such a stretch?
What's the specs for your 3/4 race cam?
 
This^^^

Go study other brands and see how many people are doing that and more with similar cubic inches.
Our maintenance man at work, his 5.0 mustang with a cold air kit, underdrive pulleys, 65mm throttle body, cat back exhaust and advanced timing and he ran in the low 13's. He also had 3.55 gears and a 5 speec
 
ask and ye shall receive.

people out here acting like mid 12's from a 318 is witchcraft or you gotta make a deal with the devil. converter and gears will easily push a 318 into the 12's

i have a 69 barracuda, full curb weight. 318/727 stock stall w/ 3.23's the motor is an honest 9.5:1 with a 3/4 race cam topped with a afb and it clicks off 13 flat at 100mph. 318 will run has a van with, you guessed it, a 318 that also runs 13's. why would mid 12's be such a stretch?
What's done to the cylinder heads, carb and intake?
 
What's the specs for your 3/4 race cam? What's done to the cylinder heads, carb and intake?

sorry, that's proprietary information. the heads are breathed on and the intake ports are matched. carb is just a stock AFB.


(on the cam, honestly i can't remember, it's been [closes eyes, rubs temples, clicks tongue] 27 years give or take. and i'm too lazy to go dig thru my files)
 
I've had a few slant 6's over the years and they got decent mileage. My 1972 gremlin x with a 258 6 cylinder got as good as mileage as my 1974 duster with a 225 and the gremlin would leave the duster behind every time
the duster outweighs the gremlin by about 600lbs
yeah, how about a more apt comparison?
 
What's the specs for your 3/4 race cam?
It may have originally way back in the day, but I've always took it to be serious street strip type cams like 240-260+ guess half would be 220-239 and RV less than. Sure it means slightly different to others.
 
ask and ye shall receive.

people out here acting like mid 12's from a 318 is witchcraft or you gotta make a deal with the devil. converter and gears will easily push a 318 into the 12's

i have a 69 barracuda, full curb weight. 318/727 stock stall w/ 3.23's the motor is an honest 9.5:1 with a 3/4 race cam topped with a afb and it clicks off 13 flat at 100mph. 318 will run has a van with, you guessed it, a 318 that also runs 13's. why would mid 12's be such a stretch?
Using slicks,dot drag radials or actual street tires?
 
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Specs on the "3/4 Race Cam" would be 3/4s of what the specs are on a "Full Race Cam".

Screenshot_20210707-195309_Messages.jpg


For comparison purposes:

20230312_165322.jpg


Factory ^^^ Mopar small block grinds.

☆☆☆☆☆
 
ask and ye shall receive.

people out here acting like mid 12's from a 318 is witchcraft or you gotta make a deal with the devil. converter and gears will easily push a 318 into the 12's

i have a 69 barracuda, full curb weight. 318/727 stock stall w/ 3.23's the motor is an honest 9.5:1 with a 3/4 race cam topped with a afb and it clicks off 13 flat at 100mph. 318 will run has a van with, you guessed it, a 318 that also runs 13's. why would mid 12's be such a stretch?
I looked up in the mopars master engine catalog and they call for mopars .508/292* cam for a 13 second 13, I think that a flat 13 can be obtained with less cam as that information is probably 25 years ago.
 
The 225 in my duster got fair mileage. Some people have luck with a mopar getting good mileage. Mine never really did. I've known alot of people over the years that had a 318 in both cars and trucks and the mileage isn't there.

If you can't get good mpg from a 318, I stand by my first reaction. "You must not know how to tune or drive." If you want to compare compacts or small engines, to a 318 what is your point. I worked on all brands of cars. Mopars were always at the top for power efficiency, and reliability. And I worked on cars when Pontiacs had Pontiac engines, Buicks had Buick engines, Oldsmobiles had Oldsmobile engines, not the cheap Chevrolet junk engines.
 
This is a beautiful '72 for 25k with the AC and 318 and in the midwest. IF I was Dan, I would have the frame all inspected by a classic car restorer shop and make sure it's legibly as nice as it shows, then buy it. Then drive it. Spent 25 seconds on Marketplace to find it.
1972 Plymouth Duster
 
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Another Gorgeous '73 with a 318 and A/C, original paint and no rust. Asking 19k and in the midwest. Found it in another 25 seconds after I found the first one in post above.
1973 Plymouth space duster

Once you cross over 15k, there are a lot of real nice Dusters for sale that need next to nothing. It isn't hard to find a quality car between 15-20k. I could buy 2 a week if I was looking and willing to travel 10 hrs in any direction from home. Dan's in Missouri? That's pretty centrally located.
 
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