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Whatever happened to the Mopar 318 engine?

ShadowsPapa

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I remember (barely) in the mid 70’s, we thought 318s sucked, even new. I had a friend with a Challenger with a 318, and I wondered even then why on earth anyone would buy that.

It felt like my ’63 Rambler 440 with a V-8 in 1972. I don’t even recall what engine that was, it was that forgettable.
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ShadowsPapa

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Just remember. That front bench seat folded all the way down, like a sleeper sofa.
Mine had reclining buckets ( I think it was the 770, a step below the Ambassador)........ but Dad's 64 wagon, yeah. I even have a couple of the seat supports in a tub of NOS AMC parts so the seat backs laid down and the whole interior of that wagon was like one big bed inside.
 

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I recently picked up a clean 2001 TJ with the idea of swapping in a 360 once the 4.0 bites the dust. The older magnum engines don't get the best mileage, nor do they make the best power, but coupled with a NV4500 and some exhaust work like in my 94 Dodge 2500 they are fun to toot around in and pretty damn bulletproof. I figure to get an '01 or '02 5.9 magnum and give it a nice refurb, then use the TJ as a long lasting fun vehicle.

That the plan at least. Long live the 5.9 Magnum.
 

Wheelin98TJ

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I remember (barely) in the mid 70’s, we thought 318s sucked, even new. I had a friend with a Challenger with a 318, and I wondered even then why on earth anyone would buy that.

It felt like my ’63 Rambler 440 with a V-8 in 1972. I don’t even recall what engine that was, it was that forgettable.
In the mid 90s when your motor options in a Grand Cherokee were 4.0 I6 or 5.2 V8, the 5.2 was a nice option. Almost 300 ft/lbs with the 5.2 vs around 220-230 with the 4.0.
 

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ShadowsPapa

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In the mid 90s when your motor options in a Grand Cherokee were 4.0 I6 or 5.2 V8, the 5.2 was a nice option. Almost 300 ft/lbs with the 5.2 vs around 220-230 with the 4.0.
The HO engines were around 240 at the flywheel. Still a good 60 under the V8..
The 4.0 heads changed over the years as did the intake manifold. The 96 and later were a more sweeping intake while the 94 like mine is the old style shape closer to that of a 1982 258. The ports were moved in the head and cams changed, as well to change HP and torque throughout the 90s.

Funny you mention this as on the way in to town this AM, a GC coming the other way had been nicely built and had a great sounding V8 rumble to it.
 

NULL POINTER

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Performance spark plugs? That's a new one for me.

Dual Edelbrock carbs - 1200 cfm, annular boosters.
RobbMc performance fuel pump.
A performance outfit called ACCEL made spark plugs for the 340 and other MOPAR engines in the early 1970's. They called them performance spark plugs. They also made an electronic distributor that you could replace the OEM points and condensor distributor with. They also had a coil to go with it, and of course they also made ACCEL spark plug wires. I think they (ACCEL) may have also made the radiator flex fan I installed. Anyway I put all that stuff in my 340 Duster 4 on the floor. I also threw an Edelbrock high rise aluminum manifold on it and replaced the Carter Thermoquad 4V with a Holley 650 4V.

I did not have a dyno so my brother-in-law's sister's second cousin, once removed measured it on his Buttox Dyno and said I gained 19.376459845 extra horsepower with all those mods.
 

Stan H

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A performance outfit called ACCEL made spark plugs for the 340 and other MOPAR engines in the early 1970's. They called them performance spark plugs. They also made an electronic distributor that you could replace the OEM points and condensor distributor with. They also had a coil to go with it, and of course they also made ACCEL spark plug wires. I think they (ACCEL) may have also made the radiator flex fan I installed. Anyway I put all that stuff in my 340 Duster 4 on the floor. I also threw an Edelbrock high rise aluminum manifold on it and replaced the Carter Thermoquad 4V with a Holley 650 4V.

I did not have a dyno so my brother-in-law's sister's second cousin, once removed measured it on his Buttox Dyno and said I gained 19.376459845 extra horsepower with all those mods.
That cracked me up !!!😂😂😂
 

ShadowsPapa

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A performance outfit called ACCEL made spark plugs for the 340 and other MOPAR engines in the early 1970's. They called them performance spark plugs. They also made an electronic distributor that you could replace the OEM points and condensor distributor with. They also had a coil to go with it, and of course they also made ACCEL spark plug wires. I think they (ACCEL) may have also made the radiator flex fan I installed. Anyway I put all that stuff in my 340 Duster 4 on the floor. I also threw an Edelbrock high rise aluminum manifold on it and replaced the Carter Thermoquad 4V with a Holley 650 4V.

I did not have a dyno so my brother-in-law's sister's second cousin, once removed measured it on his Buttox Dyno and said I gained 19.376459845 extra horsepower with all those mods.
OH, THOSE performance plugs. Yeah, I have some Accel stuff in a cabinet - a box of plug wires and so on. The performance bit was marketing....... the plug wires were typically just thicker insulation, sometimes silicone, that sort of thing. The coils - well, they were indeed often capable of "higher output voltage" but unless you have a really off-the-normal build, you waste the output above about 25Kv
You might be capable of 80,000 volts, but the build-up stops once the plug fires. Good for engines with physical issues, poor A/F ratios, extreme conditions, but don't help an otherwise healthy engine. Cool though - I seem to recall they might have been yellow?
If your engine was running on the edge, they could maintain a longer duration as the extra energy would allow longer firing - say a poor A/F ratio etc. - they'd help overcome problems, or extreme compression, lean conditions and so on - so they weren't worthless, really.
GM went the route of "high energy" because of emissions - they could fire a plug with the center electrode all but gone, worn away with 100,000 miles of use back in those days. (and it caused more trouble than it fixed).
I used to enjoy putting engines on the scope and showing the differences (where they existed).


That cracked me up !!!😂😂😂
Go out to the AMC fakebook areas where people talk about mods to their Eagle engines - how much HP they gained going with HEI, and so on - "hey, how much did you gain?" Well, my butt Dyno.......
Oh, ok, so you can't really print anything out (well, maybe you can, but I don't want to see the paperwork!)
 

NULL POINTER

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Cool though - I seem to recall they might have been yellow?

Go out to the AMC fakebook areas where people talk about mods to their Eagle engines - how much HP they gained going with HEI, and so on - "hey, how much did you gain?" Well, my butt Dyno.......

Oh, ok, so you can't really print anything out (well, maybe you can, but I don't want to see the paperwork!) LOL - hilarious comment
Yeah, their stuff was yellow, and it looked good with the chrome air filter cover. Yeah, I did a ton of top end stuff on those engines, they were so easy to work on. Replace a water pump, or thermostat, no problem. Change plugs, half an hour. Realizing today that ACCEL was mostly marketing hype, although I did like the electronic igniition distributors. Didn't need the dwell meter on them, still needed the timing light though. I still have my timing light, have not used it probably in 40 or more years. I kept it with this misguided thought that in retirement I would pick up a classic MOPAR. Never happened and instead I ended up with a few Corvettes, stopping with my 2019 Z06 Convertible 7 speed manual with a 6.2L Supercharged LT4. Nice, but now a Tesla Plaid blows it away. Even new stuff quickly becomes obsolete but at least the vette sounds good.

No idea what happened to my dwell tachometer, good riddance.
 

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ShadowsPapa

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Yeah, their stuff was yellow, and it looked good with the chrome air filter cover. Yeah, I did a ton of top end stuff on those engines, they were so easy to work on. Replace a water pump, or thermostat, no problem. Change plugs, half an hour. Realizing today that ACCEL was mostly marketing hype, although I did like the electronic igniition distributors. Didn't need the dwell meter on them, still needed the timing light though. I still have my timing light, have not used it probably in 40 or more years. I kept it with this misguided thought that in retirement I would pick up a classic MOPAR. Never happened and instead I ended up with a few Corvettes, stopping with my 2019 Z06 Convertible 7 speed manual with a 6.2L Supercharged LT4. Nice, but now a Tesla Plaid blows it away. Even new stuff quickly becomes obsolete but at least the vette sounds good.

No idea what happened to my dwell tachometer, good riddance.
Yeah, no worry about dwell migration as the rubbing block wore down. I put after-market electronic on my Javelin back in about 75 or so. Nice to not have to deal with points and "it was cool".
I have a dial-type timing light and multiple tach-dwell meters. Still have points in my 73 although i have all the stuff for a basic conversion.
My 70 I rebuilt the distributor and took it to a guy with a distributor machine (he did racing ignition systems) before I sold it in 2019, and he said it was the cleanest distributor he'd seen with points - no bounce until something like 4700 rpm and rock-steady dwell.
I have a group 19 Mallory coil for AMC but it leaked oil and a guy who used to work at Mallory said - scrap it, they are junk once that happens.
I have a Mallory dual-points distributor I had though about putting in my 73 - no vacuum advance but then - it's not built for city driving anyway.
 

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What happened to the 5.2? Same thing that happened to the original Chrysler 318 polyhead, got replaced. Never had much use for the LA engine when an RB fits in pretty much any of the same spots. People complaining about the 318 must not be remembering the LA also came in 273 and was even more anemic.
 

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The 318 was a tough motor from everything I’ve heard and researched. There are a lot better options now for lighter more powerful V8’s. The guys saying horsepower in the upper 100’s are wrong. The spec for the 318 main engines per Dodge was:
230 hp and 340 lb-ft
260 hp and 345 lb-ft
There were some years that were higher horsepower with a stock max of 290 hp.
The torque numbers are better than the V6 gas, but the V6 diesel kills it.
 

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The 318 was a tough motor from everything I’ve heard and researched. There are a lot better options now for lighter more powerful V8’s. The guys saying horsepower in the upper 100’s are wrong. The spec for the 318 main engines per Dodge was:
230 hp and 340 lb-ft
260 hp and 345 lb-ft
There were some years that were higher horsepower with a stock max of 290 hp.
The torque numbers are better than the V6 gas, but the V6 diesel kills it.
Where you getting those numbers from?
 

Zachanadandy

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The 318 was a tough motor from everything I’ve heard and researched. There are a lot better options now for lighter more powerful V8’s. The guys saying horsepower in the upper 100’s are wrong. The spec for the 318 main engines per Dodge was:
230 hp and 340 lb-ft
260 hp and 345 lb-ft
There were some years that were higher horsepower with a stock max of 290 hp.
The torque numbers are better than the V6 gas, but the V6 diesel kills it.
The power specs you quoted are for the 5.2L magnum motors for 92 and up. Basically a 318 LA motor with better heads and higher compression. Being the OP specifically stated 318 that typically refers to the non-magnum carbureted versions from the 60s thru early 90s. They were in fact as low as 150hp low compression junk. The magnum was much better but still weak compared to the modern hemis that replaced it. Definitely not worth the effort to swap in to a modern vehicle.
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