Hypothetical 318 Builds

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Rob, I saw no strokers or power adders. Are converters and gear changes allowed to make the cam work?
 
https://www.motortrend.com/how-to/ccrp-0401-mopar-318-engine/
Magnum heads 10:1 cr comp 280h cam

Mopar 318
RPMHPTQ
3,000190332
3,500241376
4,000286376
4,500321375
4,900357382
5,000363381
5,500388371
6,000398348
6,200400339
6,500393318


https://www.motortrend.com/how-to/0810phr-chrysler-318-engine/
EQ 9.85:1 cr xe275hl

RPMTQTQHPHP
BASEPORTEDBASEPORTED
3,000335335192192
3,200342340208207
3,400351356228231
3,600365369250253
3,800374379271274
4,000379384289293
4,200378383302306
4,400375383314321
4,600376382329335
4,800375386343353
5,000372384354366
5,200367383363378
5,400361379371390
5,600355374379399
5,800350371386409
6,000345365395418
6,200341360402425
6,400329345401421

https://www.motortrend.com/how-to/318-small-block-build/
Ported 302 10:1 xe268h

RPMTEST 1TEST 2TEST 3
TorqueHPTorqueHPTorqueHP
3,000334.9191.3354.1202.3349.1199.4
3,500360.7240.4378.2252.0380.7253.7
4,000376.6286.8402.3306.4401.5305.8
4,100379.3296.1402.4314.1401.6313.5
4,500374.0320.4402.5344.9400.1342.8
4,600374.0327.6403.1353.0400.6350.9
4,700373.5334.2400.6358.4408.0365.1
5,000363.9346.4389.7371.0402.0382.7
5,500344.0360.2368.3385.7386.5404.8
5,900331.1372.0347.1390.0361.4406.0
6,000328.3375.0344.0393.0353.8404.2
6,100319.4371.0339.2394.0347.8404.0

https://www.motortrend.com/how-to/0901phr-mopar-318-magnum-engine/
ported EQ 10.5:1 solid 247/247 @ fifty

On The Dyno DTS Dyno Data Performance Crankshaft 323CI Small-Block Mopar
RPMTQHP
2,500337161
2,600350173
2,700357183
2,800357190
2,900356196
3,000351201
3,100345204
3,200339207
3,300343216
3,400356230
3,500371247
3,600385264
3,700396279
3,800404292
3,900410305
4,000415316
4,100418327
4,200420336
4,300422345
4,400421353
4,500420360
4,600421369
4,700425380
4,800426390
4,900427398
5,000427407
5,100427414
5,200426421
5,300425428
5,400423435
5,500421440
5,600419446
5,700417453
5,800415458
5,900412462
6,000407465
6,100401466
6,200397469
6,300393471
6,400390475
6,500386477

https://www.motortrend.com/how-to/mopp-0312-318-long-block-bolt-ons/
stock heads cr xe262h

HORSEPOWER SUPERFLOW 901 DYNO-TESTED AT WESTECH
RPMBASEMOD 1MOD 2
2,000112
2,500137
3,000164193192
3,500182224227
4,000189248252
4,500186265274
5,000179271282
5,500262270


TORQUE SUPERFLOW 901 DYNO-TESTED AT WESTECH
RPMBASEMOD 1MOD 2
2,000292
2,500287
3,000287338336
3,500272335340
4,000248326330
4500218309319
5,000188285296
5,500250258
Interesting observation

If you look at the tq at 3000 rpm which all show, the stock 2bbl with headers makes 287 tq and the rest no matter what cam and cr make from 332-354 tq a good 40-60+ tq over stock cam, and the most built 318 also makes 332 tq @ 2500 rpm over stock 287 tq.

Hp % of tq @ rpm = 57% @ 3000 rpm = 287 tq vs 332 tq vs 354 tq = 164 hp vs 189 hp vs 202, and at 2500 rpm = 48% = 287 tq vs 332 tq = 137 hp vs 159 hp.

Cams that most would consider low rpm tq killers especially in a 318 don't show that to be the case.
 
I thought we were building our own. lol heck with the magazine or anyone else's build.
 
Interesting observation

If you look at the tq at 3000 rpm which all show, the stock 2bbl with headers makes 287 tq and the rest no matter what cam and cr make from 332-354 tq a good 40-60+ tq over stock cam, and the most built 318 also makes 332 tq @ 2500 rpm over stock 287 tq.

Hp % of tq @ rpm = 57% @ 3000 rpm = 287 tq vs 332 tq vs 354 tq = 164 hp vs 189 hp vs 202, and at 2500 rpm = 48% = 287 tq vs 332 tq = 137 hp vs 159 hp.

Cams that most would consider low rpm tq killers especially in a 318 don't show that to be the case.
Compression at 10 vs 7.5 stock is what you are seeing. Stick that same cam in a stock 318 and it would not even spin the tires in snow.
 
I thought we were building our own. lol heck with the magazine or anyone else's build.
Kinda what I was wantin, but I'm not gonna tell anybody no. It all adds to it.
 
If I was do more mild with stock heads no major porting with 218 to 230 .500 ish 110 cam 650/750 airgap depending application so

Zero decked 302 low/mid 300 hp

zero decked magnum mid/high 300 hp

quenched pad pistons 360/340 heads mid/high 300 hp
 
I've got a roller cam Teen block and a pair of Speedmaster heads. That might be a good start.
 
85 la roller cam 318, magnum heads with port work, kb hypo flat tops 0 deck .035 head gaskets so some wheres around 11.5 compression, big mutha thumper hr cam 235/249 @ 50 522/509 that will bleed off compression to a barley pump friendly level with good quench, should be ok! hughs spring kit, strip dom intake and a worked holly 650 duel line mechanical 2nds, too much compression, tooooo much cam, going in a 73 duster drag/grudge/street deal with 4:10 gears slicks and a stall, been scrounging for years bout 800 in so far and looking at 1800 tottle budget, and tired of waiting, saving for pistons now, then we'll find out!
 
Compression at 10 vs 7.5 stock is what you are seeing. Stick that same cam in a stock 318 and it would not even spin the tires in snow.
Not saying cr has nothing to do with but additional airflow is also help making low end tq, plus the low cr 318 with xe262h cam is making 45 tq over stock cam at 3000 rpm to with zero cr help and obviously the 4bbl vs 2bbl helps too.

That 10.5:1 ported EQ 247/247 477 hp has the strongest curve everywhere from 2500-6500 rpm it makes 400 hp just before 5000 rpm, 500-1200 rpms sooner than the other 400-425 hp 318's.

My observation was, most would say those cams 224 to 247 @ 50 would cost you low tq even with the higher CR but it's not showing with 5 different builds. Plus there's that Richard Holdener video a low cr 360, stock cam vs xe250h vs xe268h and shows similar down low tq gains the 250&268 make about 45tq over stock cam and same low cr on all 3 cams.

I just thought it was interesting and figured others building a 318 might.
 
Last edited:
85 la roller cam 318, magnum heads with port work, kb hypo flat tops 0 deck .035 head gaskets so some wheres around 11.5 compression, big mutha thumper hr cam 235/249 @ 50 522/509 that will bleed off compression to a barley pump friendly level with good quench, should be ok! hughs spring kit, strip dom intake and a worked holly 650 duel line mechanical 2nds, too much compression, tooooo much cam, going in a 73 duster drag/grudge/street deal with 4:10 gears slicks and a stall, been scrounging for years bout 800 in so far and looking at 1800 tottle budget, and tired of waiting, saving for pistons now, then we'll find out!
No such thing as too much! lol
 
Added Couple of in car 318 builds
https://www.motortrend.com/how-to/mopp-0311-318-engine-buildup-and-dyno-test/
https://www.motortrend.com/features/mopp-0009-1985-dodge-dart/


https://www.motortrend.com/how-to/ccrp-0401-mopar-318-engine/
Magnum heads 10:1 cr comp 280h cam

Mopar 318
RPMHPTQ
3,000190332
3,500241376
4,000286376
4,500321375
4,900357382
5,000363381
5,500388371
6,000398348
6,200400339
6,500393318


https://www.motortrend.com/how-to/0810phr-chrysler-318-engine/
EQ 9.85:1 cr xe275hl

RPMTQTQHPHP
BASEPORTEDBASEPORTED
3,000335335192192
3,200342340208207
3,400351356228231
3,600365369250253
3,800374379271274
4,000379384289293
4,200378383302306
4,400375383314321
4,600376382329335
4,800375386343353
5,000372384354366
5,200367383363378
5,400361379371390
5,600355374379399
5,800350371386409
6,000345365395418
6,200341360402425
6,400329345401421

https://www.motortrend.com/how-to/318-small-block-build/
Ported 302 10:1 xe268h

RPMTEST 1TEST 2TEST 3
TorqueHPTorqueHPTorqueHP
3,000334.9191.3354.1202.3349.1199.4
3,500360.7240.4378.2252.0380.7253.7
4,000376.6286.8402.3306.4401.5305.8
4,100379.3296.1402.4314.1401.6313.5
4,500374.0320.4402.5344.9400.1342.8
4,600374.0327.6403.1353.0400.6350.9
4,700373.5334.2400.6358.4408.0365.1
5,000363.9346.4389.7371.0402.0382.7
5,500344.0360.2368.3385.7386.5404.8
5,900331.1372.0347.1390.0361.4406.0
6,000328.3375.0344.0393.0353.8404.2
6,100319.4371.0339.2394.0347.8404.0

https://www.motortrend.com/how-to/0901phr-mopar-318-magnum-engine/
ported EQ 10.5:1 solid 247/247 @ fifty

On The Dyno DTS Dyno Data Performance Crankshaft 323CI Small-Block Mopar
RPMTQHP
2,500337161
2,600350173
2,700357183
2,800357190
2,900356196
3,000351201
3,100345204
3,200339207
3,300343216
3,400356230
3,500371247
3,600385264
3,700396279
3,800404292
3,900410305
4,000415316
4,100418327
4,200420336
4,300422345
4,400421353
4,500420360
4,600421369
4,700425380
4,800426390
4,900427398
5,000427407
5,100427414
5,200426421
5,300425428
5,400423435
5,500421440
5,600419446
5,700417453
5,800415458
5,900412462
6,000407465
6,100401466
6,200397469
6,300393471
6,400390475
6,500386477

https://www.motortrend.com/how-to/mopp-0312-318-long-block-bolt-ons/
stock heads cr xe262h

HORSEPOWER SUPERFLOW 901 DYNO-TESTED AT WESTECH
RPMBASEMOD 1MOD 2
2,000112
2,500137
3,000164193192
3,500182224227
4,000189248252
4,500186265274
5,000179271282
5,500262270


TORQUE SUPERFLOW 901 DYNO-TESTED AT WESTECH
RPMBASEMOD 1MOD 2
2,000292
2,500287
3,000287338336
3,500272335340
4,000248326330
4500218309319
5,000188285296
5,500250258

OMG! Did you really have to do that? WTF DUDE?!?!
You could have just left a link to the magazine build thread!
LMAO!!!!
Rob, I saw no strokers or power adders. Are converters and gear changes allowed to make the cam work?
This is just an “Engine only” exercise.
 
85 la roller cam 318, magnum heads with port work, kb hypo flat tops 0 deck .035 head gaskets so some wheres around 11.5 compression, big mutha thumper hr cam 235/249 @ 50 522/509 that will bleed off compression to a barley pump friendly level with good quench, should be ok! hughs spring kit, strip dom intake and a worked holly 650 duel line mechanical 2nds, too much compression, tooooo much cam, going in a 73 duster drag/grudge/street deal with 4:10 gears slicks and a stall, been scrounging for years bout 800 in so far and looking at 1800 tottle budget, and tired of waiting, saving for pistons now, then we'll find out!
What cc are the heads to get 11.5 with flat tops? With that kinda compression you gotta get quench or run race fuel.
 
What cc are the heads to get 11.5 with flat tops? With that kinda compression you gotta get quench or run race fuel.
magnum heads sposed be 62 cc's but i ant checked them yet cause gonna get valve job done and then check them, ant cut deck yet ether in case i need to adjust numbers,need pistons to measure it all out too, quench needs to be .040 to .035 for best results, the devil is in the details, or numbers!!
 
magnum heads sposed be 62 cc's but i ant checked them yet cause gonna get valve job done and then check them, ant cut deck yet ether in case i need to adjust numbers,need pistons to measure it all out too, quench needs to be .040 to .035 for best results, the devil is in the details, or numbers!!
My current slant 6 build is gonna end up bein about .022 quench distance. lol
 
thats getting tight!! whats your piston to valve distance gonna be like??
I'm using the non turbo 2.2 pistons. They have a very generous valve relief. I won't know until I mock it up, but they'll clear by a mile.
 
Here's one I built last year but haven't gotten to getting it in the car & running yet (car stuff has gone on hold due to having a baby).
73 318 block bored .060" over, factory cast crank ground 20/20, reconditioned factory rods fitted with ARP bolts & setup for floating pins, KB167s 0.013" above deck (0.051" head gasket), rotating assembly ballanced, HV oil pump, windage tray & baffled oil pan. Heads are bare China castings with a light home port job, valve job was redone on a newen cnc and assembled with ferrea valves, lunati beehive springs, B3 geometry kit and PRW 1.6 rockers.
Intake is a ported weiand action plus with 650cfm AVS2, exhaust will be headers and a twin 2.5" system.
9.8:1 compression ratio, rollmaster gold timing set & howards SFT cam [email protected]" & .574" lift with the 1.6 ratio rockers.
20230523_175359.jpg
 
Here's one I built last year but haven't gotten to getting it in the car & running yet (car stuff has gone on hold due to having a baby).
73 318 block bored .060" over, factory cast crank ground 20/20, reconditioned factory rods fitted with ARP bolts & setup for floating pins, KB167s 0.013" above deck (0.051" head gasket), rotating assembly ballanced, HV oil pump, windage tray & baffled oil pan. Heads are bare China castings with a light home port job, valve job was redone on a newen cnc and assembled with ferrea valves, lunati beehive springs, B3 geometry kit and PRW 1.6 rockers.
Intake is a ported weiand action plus with 650cfm AVS2, exhaust will be headers and a twin 2.5" system.
9.8:1 compression ratio, rollmaster gold timing set & howards SFT cam [email protected]" & .574" lift with the 1.6 ratio rockers.
View attachment 1716144700
That orda be real stout!
 
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