12 second junkyard 318

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JOHNNY MOPAR

JOHNNY MOPAR

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hi everyone this engine has probably been mentioned before but there is probably a lot out there that hadn't had the chance of reading this mopar muscle magazine article from 2003 anyway i found it very interesting being in the build of a 318 myself , as everyone says there are no '' substitute for cubic inches '' in this case a gentlemen was looking for a 360 to build for his 67 barracuda for street/strip use and hopefully run 12 seconds , but every time he went looking for a 360 he would stumble over a 318 , finally the light came on and he new he was working with a great engine builder who had a knack of wringing amazing amounts of horsepower from engines built almost entirely from stock replacement type components . wanting the engine to be still streetable they didnt set out to build a full tilt race engine , before the rebuild they dynoed the engine which was from a low mileage 73 dart , cranking out 187 hp at 3750 rpm . the engine was then bored 60 thou too 328 cubes , hypereutectic pistons 9.8;1 comp , clevitte bearings , felpro gaskets a comp cams 270h 224/224 at 50 and 470/470 lift 110 degrees , the block was topped off with original heads that were pocket ported and fitted with new 1.78 and 1.50 valves and gasket matched ports , a 340 cast iron manifold topped it off with a 625 cfm avs carter . the engine was reinstalled on the dyno , peak horsepower rose to 301 at 5000 and 343 lb/ft at 4000 rpm . they next stepped up the cam to 222/230 at 50 and 470/480 lift and 112 degrees , giving the engine a broader , flatter torque curve and increased top end power and yet docile enough to support a 750 rpm idle . back on the dyno the camshaft added 21 lb/ft at 2500 rpm and 23 hp producing 324 hp and 370 lb/ft peaked . with the second camshaft in place the cylinder heads became the cork screw , so they next added , and the critics wont like this , a set of ported 360 heads with 2.02 and 1.60 valves , back on the dyno the engine ratcheted up again producing 346 hp and 381 lb/ft of torque . for the final test a 750 cfm thermoquad was fitted and the 340 intake was cleaned up a little inside , this paid off with a final out put of 357 hp and 388 lb/ft of torque . with the engine installed in the 67 and the same hedman headers a 3.55;1 ring and pinion , and a 3000 rpm stall , the cuda laid down a 12.76 second 1/4 at 103.02 mph , a stock mopar electronic dissy was used and standard rocker gear , they were left very happy and impressed by how well this little 318/328 performed , which left them thinking how much more they could have pulled out of the little teen with alloy heads , holley dp , alloy intake , a better distributor , and maybe a little more compression and cam ,'' 318 '' THE LITTLE ENGINE THAT COULD . . .
 
I have a word for your post.... Parragraphs!

For a low 12 second run at the 1/4 mile track, 360 heads become a needed evil, which aint so evil at this point of the game. Alloy heads need not apply. (AKA ALuminum.)
I seriously think the 360 valves in the teen head will do it well. At 1.88 - 1.60 in size, it is plenty.
Also, the factory distributor is all that is needed. The addition of light springs is all you would possibly need.

MoPar used to have a "Tip's" section detailing the parts needed to run a "bracket time." For 12's it was there "231" cam. For the low 12 second bracket, they recomended there "346" mech. cam.

Alot of the build is dependent on actual useage. Track only or not.
 
I really like that engine build for it's use of stock parts.
It could have gone even faster with a after market intake and 750 dp carb.

If you notice the first dyno results-- with the stock 318 heads --was 301 hp at 5000 and 343 lb/ft at 4000 rpm.

At 4000 rpms it made it's peak torque.

This goes up even higher when installing 360 heads.
_________________________________________________________

My point is the car would have gone even quicker with a higher stall converter.
If the stock 318 heads where used you could have used a 3800 stall converter and with the 360 heads it would have loved a 4000 + stall converter.
I am not talking about any of the cheap converters, but a quality piece such as a dynamic 9 1/2 converter.(frank lupo)

With just a intake,750 hp style 4150 carb and a higher stall converter the car would have gone in the low 12 second range.
Using this same kind of thinking with a 360ci and you have yourself a 11 second ride.

Just going a little over stock here and there is what it takes.


IF YOU NOTICE THE CAR IS HOOKING.

http://image.moparmusclemagazine.com/f/27596596/0311_MOPP_01_z_18.jpg


________________________________________________________
 
I completing a project I bought,were the previous owner copied the 415hp build from engine masters.

http://www.popularhotrodding.com/enginemasters/articles/mopar/0667em_mopar_318_engine/index.html

My 318 has a forged 340 crank,eagle sir rods,kb167 pistons,zero decked,
comp cam XE275HL, specing out at 231/237-degrees duration at 0.050, and 0.525-inch lift, on a 110 degree lobe separation angle and Edelbrock Air gap intake.
I got some j bare heads with this project and was thinking that the smaller valve heads would work better.
Consider buying RHS heads from brian at IMM,but still believe the smaller valve heads would work better.Of course I will mill whatever head to 60cc chamber to get 10;1 compression.
Looking at Hughes Racing Iron Magnums and Hughes RHS heads W/ 1.92' INT, 1.620' EXH
What do you all thing about this setup?
TXDart
 
The thing is, the only "stock parts" that might normally be replaced with better stuff was the pushrods, rockers, and shafts. And from experience, they gave up some power by not at least upgrading the shafts and pushrods. The biggest "downer" of building the 318 is the pistons and you notice they changed them t a performance design. The rest of the engine is fantastic.
I'll also add that the machining quality is soooo crutial. A fantastically machined engine using factory stock parts I'd venture to guess will make about 15% more power than original assembly from the advances in quality and technology there. Things like wall finish, valve sealing, reduced harmonics from better balancing, blueprinting accuracy, etc all make for solid gains using mild parts. I've seen first hand a 2bbl 360 circle track engine gain 40hp just by changing the cylinder wall finish. And it was already at 450hp on that dyno. Same dyno, same ring gap, same ring supplier, same pistons. Nothing changed but the hone finish.
 
The most interesting part i find is the difference in power between pocket ported 675's with 1.78 and 1.50 valves and fully ported 360 heads with 2.02 and 1.6's at this cube and cam size.

What would a fully ported 675 with 1.88 1.6 valves make on the same combo?

Hysteric
 
yeah my apologies rumble it was a bit messy .
bit lazy with the enter button ,
your right the engine probably would have produced more power with 1.88 and 1.60 valves , and probably a little more torque ,
but when it all boils down i guess , if you already have a 340 or 360 to rebuild you are already at an advantage it will make more power ,
but if you have a 318 your contemplating building up for more performance , go for it you will be surprised , with the right combination that little engine can be made to haul *** with the rest of em
 
Thanks Jonny, I've done 3, 318's so far.
 
nice job on the 'teen. Cheap 360's are starting to get hard to find where I live, but 318's are still to be had for $75. You can't beat a 318 for a low buck 350 hp. Most expensive thing in mine is the forged pistons.
 
66dartman said:
nice job on the 'teen. Cheap 360's are starting to get hard to find where I live, but 318's are still to be had for $75. You can't beat a 318 for a low buck 350 hp. Most expensive thing in mine is the forged pistons.
Click to expand...

UGH! No DOUBT! Even the Hyper-U's are a bit high. But, that is about the only draw back $$$ wise about the engine.
 
Alot depends on cam and compresion. And alot is on the cam. To low on the compresion and it will effect everything from idle to WOT power. Most performance cams are ground on a 110 for that muscle car sound and chop your used to hearing. By going up to a 112 it will smooth out a little bit. At 114, it will be very smooth.

Going the otherway, down to a 108, it will have a nasty chop to it. At 106, it will be reallllly ruff.

Run as much compresion as you can for best results, period. Of course a 12-1 ratio and a RV cam will not mix so well and probably require race fuel, but I think you get the picture. The key word of the day is balance.
 
Stroker S: I like the comment from the story (great story Btw thanks)
Rockcrusher Tech

So how are we going to do it? With complete Flintstonian technology: a big motor, a small car and lots of used parts. We’ll also use many of the tips and tricks we give you every month. We thought about building a 454 Nova (too easy); a 455 Buick, Olds or Pontiac (been there, done that); or a 460 Maverick (would’ve been cool), but the best answer was a 440 Mopar A-body. Those cars and motors are dirt cheap, fast, reliable and so simple that anyone who can fog a mirror can build one.
 
moper said:
The thing is, the only "stock parts" that might normally be replaced with better stuff was the pushrods, rockers, and shafts. And from experience, they gave up some power by not at least upgrading the shafts and pushrods. The biggest "downer" of building the 318 is the pistons and you notice they changed them t a performance design. The rest of the engine is fantastic.
I'll also add that the machining quality is soooo crutial. A fantastically machined engine using factory stock parts I'd venture to guess will make about 15% more power than original assembly from the advances in quality and technology there. Things like wall finish, valve sealing, reduced harmonics from better balancing, blueprinting accuracy, etc all make for solid gains using mild parts. I've seen first hand a 2bbl 360 circle track engine gain 40hp just by changing the cylinder wall finish. And it was already at 450hp on that dyno. Same dyno, same ring gap, same ring supplier, same pistons. Nothing changed but the hone finish.
Click to expand...
that right there is amazing.and i paid for excellent machine work!
 
:notworth:
moper said:
The thing is, the only "stock parts" that might normally be replaced with better stuff was the pushrods, rockers, and shafts. And from experience, they gave up some power by not at least upgrading the shafts and pushrods. The biggest "downer" of building the 318 is the pistons and you notice they changed them t a performance design. The rest of the engine is fantastic.
I'll also add that the machining quality is soooo crutial. A fantastically machined engine using factory stock parts I'd venture to guess will make about 15% more power than original assembly from the advances in quality and technology there. Things like wall finish, valve sealing, reduced harmonics from better balancing, blueprinting accuracy, etc all make for solid gains using mild parts. I've seen first hand a 2bbl 360 circle track engine gain 40hp just by changing the cylinder wall finish. And it was already at 450hp on that dyno. Same dyno, same ring gap, same ring supplier, same pistons. Nothing changed but the hone finish.
Click to expand...
that right there is amazing.and i paid for excellent machine work!
 
JOHNNY MOPAR said:
hi everyone this engine has probably been mentioned before but there is probably a lot out there that hadn't had the chance of reading this mopar muscle magazine article from 2003 anyway i found it very interesting being in the build of a 318 myself , as everyone says there are no '' substitute for cubic inches '' in this case a gentlemen was looking for a 360 to build for his 67 barracuda for street/strip use and hopefully run 12 seconds , but every time he went looking for a 360 he would stumble over a 318 , finally the light came on and he new he was working with a great engine builder who had a knack of wringing amazing amounts of horsepower from engines built almost entirely from stock replacement type components . wanting the engine to be still streetable they didnt set out to build a full tilt race engine , before the rebuild they dynoed the engine which was from a low mileage 73 dart , cranking out 187 hp at 3750 rpm . the engine was then bored 60 thou too 328 cubes , hypereutectic pistons 9.8;1 comp , clevitte bearings , felpro gaskets a comp cams 270h 224/224 at 50 and 470/470 lift 110 degrees , the block was topped off with original heads that were pocket ported and fitted with new 1.78 and 1.50 valves and gasket matched ports , a 340 cast iron manifold topped it off with a 625 cfm avs carter . the engine was reinstalled on the dyno , peak horsepower rose to 301 at 5000 and 343 lb/ft at 4000 rpm . they next stepped up the cam to 222/230 at 50 and 470/480 lift and 112 degrees , giving the engine a broader , flatter torque curve and increased top end power and yet docile enough to support a 750 rpm idle . back on the dyno the camshaft added 21 lb/ft at 2500 rpm and 23 hp producing 324 hp and 370 lb/ft peaked . with the second camshaft in place the cylinder heads became the cork screw , so they next added , and the critics wont like this , a set of ported 360 heads with 2.02 and 1.60 valves , back on the dyno the engine ratcheted up again producing 346 hp and 381 lb/ft of torque . for the final test a 750 cfm thermoquad was fitted and the 340 intake was cleaned up a little inside , this paid off with a final out put of 357 hp and 388 lb/ft of torque . with the engine installed in the 67 and the same hedman headers a 3.55;1 ring and pinion , and a 3000 rpm stall , the cuda laid down a 12.76 second 1/4 at 103.02 mph , a stock mopar electronic dissy was used and standard rocker gear , they were left very happy and impressed by how well this little 318/328 performed , which left them thinking how much more they could have pulled out of the little teen with alloy heads , holley dp , alloy intake , a better distributor , and maybe a little more compression and cam ,'' 318 '' THE LITTLE ENGINE THAT COULD . . .
Click to expand...

I have a 3500 stall that would help it run even better!!! for a 904!
 
You guys are way more talented to me....... Took me ported X heads, solid roller cam in the 280s, 3500 stall, and a worked over port O Sonic to get to 11.50's...........
 
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