Hypothetical 318 Builds

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Fun to argue with people that 318s were always low compression dogs. First couple of years they were not. Only when the 340 came out and they needed to widen the gap between the performance of the new 340 and the 318 for the marketing to sell the new 340 did the compression tank.

Interesting note, I was looking in a 1973 Motors Manual and noticed for 1972 the 318 had more compression than the 340 by a couple tenths of compression.
 
For a low buck 318, I'll share the 318 build in my sons 73 Dart. 73 original 318 maybe 60,000 miles on it. Factory AC, black and white cloth interior and disc brakes. Added 15 x 6.5 B-Body Rallyes and front factory sway bar. We got it with 30,000 original miles, he is the third owner. 273 Commando intake, 273 4295s AFB carb and choke, 340 distributor, stock exhaust manifolds, custom dual exhaust, Cloyes double roller timing set, Mopar Performance HFT cam and lifter set P4452757 (.410 In and .425 Ex x 211 In and 218 Ex @ .050 on 110 centerline), 727 trans, factory 2.76 gears in a 7 1/4 Sure Grip. Runs out real nice highway cruiser and gets 20+ mpg.
 
For a low buck 318, I'll share the 318 build in my sons 73 Dart. 73 original 318 maybe 60,000 miles on it. Factory AC, black and white cloth interior and disc brakes. Added 15 x 6.5 B-Body Rallyes and front factory sway bar. We got it with 30,000 original miles, he is the third owner. 273 Commando intake, 273 4295s AFB carb and choke, 340 distributor, stock exhaust manifolds, custom dual exhaust, Cloyes double roller timing set, Mopar Performance HFT cam and lifter set P4452757 (.410 In and .425 Ex x 211 In and 218 Ex @ .050 on 110 centerline), 727 trans, factory 2.76 gears in a 7 1/4 Sure Grip. Runs out real nice highway cruiser and gets 20+ mpg.
Perfect for most of the car show cruisers here. Nice. Guessing 275 horse? May be a little more. A horsepower number doesn't mean a lot as long as the combination runs well for the owner. A number is just a good comparison number between different combinations. Tall tires and the rear gear slows the combination down but if tire boiling isn't what you want, it's not a real issue. The tires and gear make it up on the MPG end.
 
Perfect for most of the car show cruisers here. Nice. Guessing 275 horse? May be a little more. A horsepower number doesn't mean a lot as long as the combination runs well for the owner. A number is just a good comparison number between different combinations. Tall tires and the rear gear slows the combination down but if tire boiling isn't what you want, it's not a real issue. The tires and gear make it up on the MPG end.

I didn't want it too fast, he had already admitted street racing @ 100 mph in Baltimore, MD with the 2 barrel stock 318 as a teenager. I can never guess horse power. It will never boil the tires but gets going pretty quick and cruises all day long at 70 mph and idles well with the AC on. He loves the car, he has probably had it for 20 years now.
 
I didn't want it too fast, he had already admitted street racing @ 100 mph in Baltimore, MD with the 2 barrel stock 318 as a teenager. I can never guess horse power. It will never boil the tires but gets going pretty quick and cruises all day long at 70 mph and idles well with the AC on. He loves the car, he has probably had it for 20 years now.
Now that's perfect.
 
I'm sticking my 318 in a gutted 63 2 door post Dart.
any takers. lol
 
Perfect for most of the car show cruisers here. Nice. Guessing 275 horse? May be a little more. A horsepower number doesn't mean a lot as long as the combination runs well for the owner. A number is just a good comparison number between different combinations. Tall tires and the rear gear slows the combination down but if tire boiling isn't what you want, it's not a real issue. The tires and gear make it up on the MPG end.

I’ll run the model tonight
 
I’ll run the model tonight
I have Desktop Dyno on an old laptop somewhere around here. I'll let you run the numbers. There again, just a number but fun to have just to compare. I liked DD for different cam specs.
 
Perfect for most of the car show cruisers here. Nice. Guessing 275 horse? May be a little more. A horsepower number doesn't mean a lot as long as the combination runs well for the owner. A number is just a good comparison number between different combinations. Tall tires and the rear gear slows the combination down but if tire boiling isn't what you want, it's not a real issue. The tires and gear make it up on the MPG end.

Here you go Mike. I thought that 275 was way too high for stock heads and that torque type camshaft. I used the single flow number the example 340 used for the heads. I put in Rusty's build, 66fs build, my Daughters Duster an almost identical build BUT with Toth heads that I have real flow data for the model and my 360 that is in the Valiant with real flow data from Edelbrock. This shows why I went to the expense of the Toth heads for the Duster as even with a nice torque cam you can get significant gains at higher RPM with some flow.... if you play around with the model long enough you will see that there are 2 thing that drive EVERYTHING..... head flow and exhaust scavenging.... put all your money into heads and headers and the rest just follows.

 
Here you go Mike. I thought that 275 was way too high for stock heads and that torque type camshaft. I used the single flow number the example 340 used for the heads. I put in Rusty's build, 66fs build, my Daughters Duster an almost identical build BUT with Toth heads that I have real flow data for the model and my 360 that is in the Valiant with real flow data from Edelbrock. This shows why I went to the expense of the Toth heads for the Duster as even with a nice torque cam you can get significant gains at higher RPM with some flow.... if you play around with the model long enough you will see that there are 2 thing that drive EVERYTHING..... head flow and exhaust scavenging.... put all your money into heads and headers and the rest just follows.


Thanks. Looks like those heads are working. I wish I had my 273 heads flowed. Just for baseline numbers.



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How about an old-school 323” with max ported W2 heads, big solid roller and a tunnel ram? Like a ‘70s Modified Eliminator combo. Maybe use a lightened 273 crank and some hard block and all the oiling mods you can throw at it. Spin it to 8,000 rpm with a clutchless 4 speed and let it eat!

Only ‘problem’ with that type of combo would be the pistons and rods - what would you use? 318 pistons are generally tall/heavy although the 340 had no problem revving with giant slugs. Could you even fit aluminum rods in a .030” over 318?
 
1969 318 hone,ring, bearings and second to the smallest purple cam at the time? Been a while. Heads mild Port work. If any gain likely taken away with manifolds. Heads rebuilt with springs to match cam. Street master intake, 4 barrel and windage tray. Mopar performance electric ignition.
On the mild side. Performed well and got 20 mpg on the highway. Good balance between power and efficiency
sounds like one I built 30 years ago I loved that engine. it was a 69 engine too.
 
Second 318 build for me. ICON Premium Forged Pistons IC844.030, 9.0 compression with 70cc chambers. J heads with 1.88 intake valves 1.60 intake valves, 340 valve springs, Viton seals, milled .020 on block surface, milled .019 on the intake surface, match ports, and clean up the bowls competition valve job,. Bore and hone with torque plates, Sealed Power or Total Seal file to fit rings, mains torqued to 85 ft lb. True roller timing set, Racer Brown ST1 (.450 lift and 226 duration @ .050 on 105 intake center) solid lifter flat tappet cam, 273 rockers, shafts, and push rods, hardened tip oil pump shaft, windage tray, high volume 65 psi oil pump, balanced forged crank, 340 bushed rods with ARP rod bolts, 71 340 intake, 72 TQ 6138, 72 340 electronic ignition distributor with a chrome box. 70 340 exhaust manifolds and 2 1/4 dual exhaust. 3 row factory radiator and the MP fan and clutch. 4 speed and 8 3/4 rear of course.
 
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This is a great thread. Thanks for starting it. I’m not as educated as some of you when the numbers start flying around these posts but it seems like I could ask you guys a couple questions.

I will eventually be (re)building a 318 for a 54 Plymouth Plaza Suburban I have. Nothing special but I want to make it bulletproof since my wife will drive it and she is not a “car” person.

I have two 318s that have been sitting in my garage for a few years. One ran in my dart and the other was given to me by a friend. I don’t know what car or truck either of them started life in and I don’t know what has been done to the internal if anything. I’m gonna use of hat I have from both and make the best 318 I can.

With that said, which block do you recommend?
Cast 4104230 dated 8/31/79
Cast 4006730 dated 9/13/76

I have two sets of cast heads.
Cast 4027163
I have an Edelbrock performer intake and Hedman headers.

I will use what I have if it’s good and replace items as needed to make one good engine.

Thoughts?

image.jpg
 
This is a great thread. Thanks for starting it. I’m not as educated as some of you when the numbers start flying around these posts but it seems like I could ask you guys a couple questions.

I will eventually be (re)building a 318 for a 54 Plymouth Plaza Suburban I have. Nothing special but I want to make it bulletproof since my wife will drive it and she is not a “car” person.

I have two 318s that have been sitting in my garage for a few years. One ran in my dart and the other was given to me by a friend. I don’t know what car or truck either of them started life in and I don’t know what has been done to the internal if anything. I’m gonna use of hat I have from both and make the best 318 I can.

With that said, which block do you recommend?
Cast 4104230 dated 8/31/79
Cast 4006730 dated 9/13/76

I have two sets of cast heads.
Cast 4027163
I have an Edelbrock performer intake and Hedman headers.

I will use what I have if it’s good and replace items as needed to make one good engine.

Thoughts?

Check both blocks out and use the one with the least wear. Same for the cranks. Looks like you have a Performer and an original 340 intake. Use the best pair of heads, with the valves as close to the chamber and no corrosion. The heads should have induction hardened exhaust seats, so should be good. Plug the holes on the exhaust ports with set screws. Have the intake valves back cut. Run a high pressure oil pump spring and a windage tray. Use a true roller timing chain and a cam from 268 to 260 duration and about .450 lift. If you are buying a new carb, I'd run an AVS2 or a Street Demon around 650 to cfm. If a used carb, then anything from a small TQ, Qjet, 273 AFB or 340 AVS should bolt on and run sweet. Last thing would be an electronic ignition with a quick curve.
 
Check both blocks out and use the one with the least wear. Same for the cranks. Looks like you have a Performer and an original 340 intake. Use the best pair of heads, with the valves as close to the chamber and no corrosion. The heads should have induction hardened exhaust seats, so should be good. Plug the holes on the exhaust ports with set screws. Have the intake valves back cut. Run a high pressure oil pump spring and a windage tray. Use a true roller timing chain and a cam from 268 to 260 duration and about .450 lift. If you are buying a new carb, I'd run an AVS2 or a Street Demon around 650 to cfm. If a used carb, then anything from a small TQ, Qjet, 273 AFB or 340 AVS should bolt on and run sweet. Last thing would be an electronic ignition with a quick curve.
Thank you very much for the advise!
 
I had a 318 in my Duster, KB pistons 9.4-1 comp with stock Edelbrock heads, cam .545 lift cam, air gap intake, 430 gears, great street car! drove it to the track, full interior went 11.70s on good day and 11.80s in bad weather. 318s run great just need to have the combo right.
 
318 + 030
KB167s
Zero Decked
Balanced
Aeroflow Heads
9.4:1 comp
Comp XE268 cam
LD340 and Holley 600 Vac Sec
Shorty Headers, 2.5" dual exhaust
4 speed
2.92 Hwy diff (for now)

First start up very close!
 
318 + 030
KB167s
Zero Decked
Balanced
Aeroflow Heads
9.4:1 comp
Comp XE268 cam
LD340 and Holley 600 Vac Sec
Shorty Headers, 2.5" dual exhaust
4 speed
2.92 Hwy diff (for now)

First start up very close!
Photos and a video when you get it going. I would estimate 350 horse.
 
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