198 vs. 225 revisited

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kittypancake

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Anyone have any expierience/info on MPG comparisons between 198 + 225? I think I will do a quick re-ring to replace the oil burner I've got now. Started taking spare 225 + 198 apart and the inside of the 198 looks as clean as an OR.

So I got to thinking...What was the thought process in producing the 198? Why was it made for only 2 years? Did it absolutely suck?
 
Hi,
The 198 was made for 5 years.....1970 thru 1974. I have a '74 Duster with this engine but have not driven it enough to do a mileage comparison. Would have to be a same year comparison to be fair. For instance, I bet a '70 model A-body with a 225 could match a heavier '74 A-body with a 198 in MPGs. I think the 170 ran its course and a larger more powerful entry level six was needed with the cars growing bigger and weighed down with more options.
 
The mileage between all three was close to the same. Not really stellar for a 6 but pretty good. I bet there's a toyota store close by if you want mileage. lol

Sorry....you kinda left it wide open
 
StrokerScamp said:
I bet there's a toyota store close by if you want mileage. lol
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If you want a laugh look at the mpg of a new v6 tacoma. They like to advertise how fuel efficient they are, but that ignores all the inefficient models that americans like to buy. Tundra, sequoia, 4runner, fjcruiser, land cruiser, v6 tacoma, v6 higlander, v6 sienna, v6 rav4. All of those vehicles have an average of around 19 mpg. But since the prius runs on moonbeams and good intentions the world has no problems.
 
mcnoople said:
If you want a laugh look at the mpg of a new v6 tacoma. They like to advertise how fuel efficient they are, but that ignores all the inefficient models that americans like to buy. Tundra, sequoia, 4runner, fjcruiser, land cruiser, v6 tacoma, v6 higlander, v6 sienna, v6 rav4. All of those vehicles have an average of around 19 mpg. But since the prius runs on moonbeams and good intentions the world has no problems.
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I know. lol I worked on toyotas for years...in fact am still toyota certified. I will say one thing about them.....the V6 in the little trucks will haul ***. lol
 
I guess I don't understand why an early A with a slant can't get 30 mpg. I'll know in a few years when I finish upgrading mine. With modern engine controls, it should be as efficient as a 4.0L Jeep engine. I will have to live with a non-lockup torque converter though. I have electronic ignition already and plan EFI and spark control eventually.

The 198 should give slightly better mileage if everything else is comparable. Most important for mileage is compression ratio, intake valve opening (less lift better), spark timing, gear ratio (rear end), and carburetor (smaller better).
 
BillGrissom said:
I guess I don't understand why an early A with a slant can't get 30 mpg. I'll know in a few years when I finish upgrading mine. With modern engine controls, it should be as efficient as a 4.0L Jeep engine. I will have to live with a non-lockup torque converter though. I have electronic ignition already and plan EFI and spark control eventually.

The 198 should give slightly better mileage if everything else is comparable. Most important for mileage is compression ratio, intake valve opening (less lift better), spark timing, gear ratio (rear end), and carburetor (smaller better).
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Less lift? How does that help?
 
It's all in the head. THey ain't the most efficient things in the world.......although extremely reliable.
 
StrokerScamp said:
It's all in the head. THey ain't the most efficient things in the world.......although extremely reliable.
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Perhaps I mistakenly assumed making it a little less asthmatic would help efficiency, hence improve gas mileage. Not a radical cam but porting, oversize valves, oversized or dual exhaust, and/or 1.6 rockers.
 
BillGrissom said:
I guess I don't understand why an early A with a slant can't get 30 mpg. I'll know in a few years when I finish upgrading mine. With modern engine controls, it should be as efficient as a 4.0L Jeep engine. I will have to live with a non-lockup torque converter though. I have electronic ignition already and plan EFI and spark control eventually.

The 198 should give slightly better mileage if everything else is comparable. Most important for mileage is compression ratio, intake valve opening (less lift better), spark timing, gear ratio (rear end), and carburetor (smaller better).
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you must have mixed some Prius moon beams in your tank to get 30mg out of a jeep 4.0

also, in a few years? don't wait too long because 2025 EPA mandate is 54 mpg.
 
kittypancake said:
Perhaps I mistakenly assumed making it a little less asthmatic would help efficiency, hence improve gas mileage. Not a radical cam but porting, oversize valves, oversized or dual exhaust, and/or 1.6 rockers.
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No, it wasn't a mistake.....it will help. It's just that they'll never be 30 plus MPG beasts, no matter what some people claim. Simply not gonna happen.
 
340duster340 said:
you must have mixed some Prius moon beams in your tank to get 30mg out of a jeep 4.0

also, in a few years? don't wait too long because 2025 EPA mandate is 54 mpg.
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If it's a 2WD, they'll do it. My boss drives a AWD Grand Cherokee and it gets like 24.
 
i still doubt 30mpg. i have a 97 jeep cherokee sport with the 4.0L and i has the selectable transfer case 2wd/4hi/4lo. best i ever got hwy was 20MPG.
 
StrokerScamp said:
No, it wasn't a mistake.....it will help. It's just that they'll never be 30 plus MPG beasts, no matter what some people claim. Simply not gonna happen.
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Um...I never said anything about 30 mpg...although I think it may be possible 30mpg driving VERY conservativley on the highway only...no way do I think it can achieve an OVERALL 30mpg...mine has the aerodynamics of a major kitchen appliance
 
It is possible to get 30 mpg with a slant six, "A" body. There are several on this site and ss.org that get very close. I have a 64 Valiant in my yard with a 170 and 3 speed std trans, that gets upper 20's. I think It will break 30, when I install a A833OD in place of the 3sp. The motor is .060 over honed with a block plate, deck cut to .005 deck hight, balanced, Good valve job and head cut to give an honest 9.5 CR (don't remember the cc's). Small Mopar performance cam (244 lift). Holley 1920 carb on a stock intake, stock exhaust manifold, with a low restriction exhaust system.

PS: I also have a 86 Toyota PU, that gets 18-19 MPG towing my 5500 lb race car trailer. 371,500 miles on the 22RE engine and never had the head off. Just two timing sets.
 
The recipe for a 30 mpg slant. 64 dart 2dr 170 efi with T56 trans. If anyone is willing to send me all the money required I will build myself one and then say thank you.:toothy8:
 
Best I ever did with the Duster was 26 something on 93. Stock to the bone except for the "triple split exhaust!"

Manifold came off in 3 pieces when I pulled the head and went 2bbl and headers. The exhaust was split from a single to duals.

3:23's and a 3 speed. I haven't been out on the road in a couple years. I used to average 22 cruising to and from Florida at 80-82 mph. Stock valves, cam, lots of porting and .090 off the bottom.
 
its all about mechanical efficency... this all includes friction, VE, and load...

you need to have the engine get a FULL charge so it can have a full burn, more power = less foot...
 
805moparkid said:
its all about mechanical efficency... this all includes friction, VE, and load...

you need to have the engine get a FULL charge so it can have a full burn, more power = less foot...
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Uhm...this maybe a stupibd question, what's "VE"?
 
kittypancake said:
What was the thought process in producing the 198?
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One engine block (the taller "RG" item) instead of two (the LG 170 and the RG 225); creating a small basic-equipment engine using only different crank and rods and carburetor. Less expensive to produce that way, and by '70 the A-bodies were growing heavier and rear axle ratios were getting taller and the 170 had gone from underpowered to severely underpowered, so the 28 additional cubic inches helped.

Why was it made for only 2 years? Did it absolutely suck?
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No, it didn't suck. But at the same time as cheap-and-nasty emission control strategies were taking a big chunk out of engine performance and primitive safety engineering was weighing the cars down heavily, putting the 198 in the same position as the 170 in 1969, Chrysler was running low on money and realized it would cost even less to make just one 6-cylinder engine rather than two. Add to that the forthcoming-at-the-time changeover to a cast crankshaft and the forthcoming-at-the-time 2bbl package for the 225.
 
StrokerScamp said:
No, it wasn't a mistake.....it will help. It's just that they'll never be 30 plus MPG beasts, no matter what some people claim. Simply not gonna happen.
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We've fought this battle here before, but I documented my feather getting 31.4 over several tank fulls on a road trip after putting a new clutch in. It had 288,000 miles on it at the time and was so tired you could turn the motor over easily by hand by grabbing the flywheel ring gear. Admittedly, this was with 36 PSI in the tires and it was still running the 195/78/14s.
For what it's worth, the car still has it's unmolested, unrebuilt, unmodified original powertrain so far, is still going to work everyday, and the odometer rolled over for the third time at three thirty in the afternoon two Saturdays ago.
 
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