318/360 Crank/347 running on Dyno

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Y'all are starting to sound like a bunch of old woman arguing about the weather....lol. The man built a nice little motor that was well thought out and assembled, broken in and made a nice little power curve. Nuff said! Kudos to him! Hope his wife goes through a lot of tires!
 
usually if you step away from normal you take a bit of heat.
Kudos to the builder!
...3.90 x 3.62 has been good enough for the Corvette for many years!
 
Didn't know about the LS bore and stroke, but I've always wondered what prompted Mopar to build the 5.7 Hemi with what is virtually a 318 bore (3.92") and a 360 crank (3.58"). Funny that GM ended up with a similar combo, makes me wonder if it has some kind of emissions connection, or if the combination works well together to build decent power without having an overly large motor.
 
I think this is a GREAT build. There are plenty of folks that like to piss on the lowly 318 as 'unworthy' and it's great to see one built to perform. I ran an early ('68-69) stock 318 2bbl in my Duster for a bit while I played with the 340 and it was no slouch. I also like the fact that he stroked it by using the 360 crank instead of buying another 318 crank. The motor makes good torque/HP and will get good mileage. What more could you ask?
Could you give a few more details about the '302 heads? I'm not familiar...
 
302 heads are a closed swirl chamber 318 smog head-they were installed in late '84 318s up to '91. Small chambers, with small shrouded valves. Hot Rod did a junkyard jewel 318 build with a set of those several years ago; netted like 375hp after porting them out to 340/360 port sizes, installed 1.88/1.60 valves, and did some serious chamber work. They used a 200k short block with hand blended valve reliefs, and notched the cylinders a little with a Comp XE275HL cam, and IIRC, a dual plane intake, stock rockers, and some 1 5/8" headers.

If you either want a stock 318 or you don't mind putting the work into them, they can be made to run well, but the money you'd sink into them could arguably be more easily invested in a set of Magnums for a bolt on increase in power and torque. But-they retain the LA rocker gear...and I think that's why they're very attractive to some folks.

EDIT: I stand corrected-they made 404 with it, after some swapping of intakes and carbs. Another thing about those heads is they don't require much timing lead because of the fast burn chambers. The turbulence propogates a very quick combustion, so less timing is needed, therefore less prone to detonation. Here's the article:

http://www.hotrod.com/howto/113_0304_318_small_block_build/viewall.html
 
ir3333 said:
usually if you step away from normal you take a bit of heat.
Kudos to the builder!
...3.90 x 3.62 has been good enough for the Corvette for many years!
Click to expand...
Didn't see anyone give the OP any "heat" He built a nice motor for sure. And it don't go in a corvette, and in fact, a 350 has been good for a corvette for a lot of years too, don't mean we want one though!
 
I've clearly mixed up two engine builds...I would've swore they used an XE275HL cam in that build, but clearly they used an XE268, and there are some other details I mixed up in there...sorry about the lack of clarity.
 
txstang84 said:
302 heads are a closed swirl chamber 318 smog head-they were installed in late '84 318s up to '91. Small chambers, with small shrouded valves. Hot Rod did a junkyard jewel 318 build with a set of those several years ago; netted like 375hp after porting them out to 340/360 port sizes, installed 1.88/1.60 valves, and did some serious chamber work. They used a 200k short block with hand blended valve reliefs, and notched the cylinders a little with a Comp XE275HL cam, and IIRC, a dual plane intake, stock rockers, and some 1 5/8" headers.

If you either want a stock 318 or you don't mind putting the work into them, they can be made to run well, but the money you'd sink into them could arguably be more easily invested in a set of Magnums for a bolt on increase in power and torque. But-they retain the LA rocker gear...and I think that's why they're very attractive to some folks.

EDIT: I stand corrected-they made 404 with it, after some swapping of intakes and carbs. Another thing about those heads is they don't require much timing lead because of the fast burn chambers. The turbulence propogates a very quick combustion, so less timing is needed, therefore less prone to detonation. Here's the article:

http://www.hotrod.com/howto/113_0304_318_small_block_build/viewall.html
Click to expand...


Great read! Thanks for the link! This sounds like exactly what my kid is looking for on his 'teen Duster!
 
I actually really love this build, good torque curve and should be really snappy on the street.
 
I like this combination. It had a good torque curve,and some h.p. Wasn't built, to rump or street race. This in a pre smog a body ,might surprise you.....
 
Captainkirk said:
Great read! Thanks for the link! This sounds like exactly what my kid is looking for on his 'teen Duster!
Click to expand...
You will need to spend 75% of your budget on a pro to port the heads to that level. To me it doesn't make any sense and I can do it myself. Drop a set of Magnums or RHS's or EQ's on it and enjoy. I have spoken with Steve Dulcich many times and he readily admits that porting a set of '302's to that level is really difficult and time consuming. I'm going to say something that will get a lot of peoples backs up but here goes ----FORGET 302 HEAD CASTINGS--Get yourself some Magnum/RHS/EQ's and drop them on. J.Rob
 
Abodybomber said:
I like this combination. It had a good torque curve,and some h.p. Wasn't built, to rump or street race. This in a pre smog a body ,might surprise you.....
Click to expand...

Thankyou A-body Bomber! This guy ^^^^^^^^^^ gets it. I bet this thing pulls like an electric motor its so smooth.

Who wants a little video of it running on the dyno? J.Rob
 
frosty_the_punk said:
I actually really love this build, good torque curve and should be really snappy on the street.
Click to expand...

Frosty gets it as well. A stock stroke 318 would have a hard time to make 350 ft/lbs at peak let alone for almost a 2000 rpm band. J.Rob
 
ir3333 said:
usually if you step away from normal you take a bit of heat.
Kudos to the builder!
...3.90 x 3.62 has been good enough for the Corvette for many years!
Click to expand...

I built this engine using the parts I did for primarily 2 reasons.

1. To see what all the hype was about these '302 heads

2. To see just how a 'teen would respond to the stroke of a 360.

Summary:

1. '302 heads do have a nice chamber--that's no big deal on a mild low compression build. I could and have milled open chamber heads to perform as well or better. Anyone actively seeking and going out of their way for these heads--needs to understand that Magnum heads and their variants are FAR superior. If there was a class of racing that specifically listed these '302's as THE only casting to use I still WOULDN'T use these heads. I would EDM a fake casting number into a set of Magnums.

2. The added stroke and piston speed did just what you would expect to the 318. It added cubes which added torque production. In fact I have pulled this engine down to 2200 rpm and it still made 340+ ft/lbs and carried over 350 ft/lbs all the way to 4600 rpm. I know this engine would be a bloody good daily driver which is exactly what I built it for.

It was a neat experiment for sure. Maybe I should do another one with '302 heads and then switch heads to Magnums and then switch manifolds and then switch cams and then......You get the picture. Thanks for the interest and positive responses guys, but if you want big power then start with a 360. If you want even bigger power then build a stroker. If you want any kind of power use Magnum heads/NOT '302 castings. If you want an awesome smooth economical 318 based build with torque everywhere then copy this build. J.Rob
 
...and I reiterate...

...they can be made to run well, but the money you'd sink into them could arguably be more easily invested in a set of Magnums for a bolt on increase in power and torque...
Click to expand...

Mopar Muscle did a build on the heels of the Hot Rod build and they used KB pistons, a COMP 280H Magnum cam, and a set of untouched Magnum heads...it squeaked out over 400. IMO, they did have a better setup from the get go.

I'm kinda surprised it made power as high as it did with those heads, but if I were looking for a cruisin' engine-that would be a fantastic candidate for my '72 Scamp. And I'll vote my support for Tim's assessment that it would likely surprise most in a [pre-smog] A body.
 
Wish someone made a low dollar off the shelf piston for this combination. Mopar has a 3.58 cast crank in the 318/340 main size, or have a 360 crank turned down. Any rod would do with no fitment issues. We're just missing the piston. KB are you listening lol? I agree with RAM, the 302 heads are an over hyped casting. It takes a lot of work just bring them up to Magnum level, which I also agree are the perfect head for this kind of motor. LA bolt pattern EQs with a job valve job , and a little cleanup work would be my pick.
 
So what vehicles did the stock Magnum heads come on? And what are they fetching (average) for a set?
 
What pistons were used and about how much did it cost to have the crank cut?

This sounds like something I'd like to try. I have a few 318's.
 
Captainkirk said:
So what vehicles did the stock Magnum heads come on? And what are they fetching (average) for a set?
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Late '91 to mid '02 5.2 and 5.9 (or whenever they dropped the 5.2/5.9 Magnum V8's. Dodge Dakota's, Ram's and full size vans.

You can usually find them for $100 or less here. Very hard to find a set not cracked between the valves in the combustion chamber.
 
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