boring my 318

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umm i have how to build a small block

and how to hot rod your small block

and in it it says that the small vale 360head would be good but i guess not really becasue you have to do alot to make it work well with your setup
 
so what heads would be best for street performance like 13secs with the 318 and not having to do alot to make them work thanks
 
wait so 302 heads are different from magnum heads? if they different what do i have to do to make older LA parts fit... nothing? becasue you said the header ports on the mags. would be big for the head or a little something like that
 
Slow down. tow different designs. Magnum, and LA. "302" castings are for LAs. Those are the pre-92 small V8s, including 273, 318, 340, and 360s. All heads interchange on those except a few early 273s that take a special intake. Post '92 all are Magnums, and they take a different intake (or get re-drilled) and need different lifters and pushrods. The "302s" are LA heads. You bolt them on, and run them. Your books are a source of info. But they are not bibles. The more info you get, the less some of the build ideas in them will make sense. Running 360 heads instead of good 302s ona 318 street engine is an example of this.
 
Well said.


post 51;
The small valve 360 had does very well on very pumped up 318's. They'll do OK with small cams on a mild build. But I would rather max what I have than crutch it.

post 52;

Best heads are subjective. Things like money in the pocket can dictate.
Magnum heads best OOTB cross over head.
302 best OE, "LA" head
360 head, best for on the cheap upgrade rather than porting the 302 to work best. Do realize you could potentaily be giving up 40+ pounds of torque with 360 heads.
 
I bought my "...302" heads from aerohead racing, a division of Indy cylinder head.

http://www.aeroheadracing.com/id6.html

I ordered them with the 1.88/1.60 valves ( as advertised ) a back-cut on the intake, and hardened seats. With shipping, they were $600 even.

head1.jpg


The "...302" casting heads are the same configuration as earlier heads, as far as intake, exhaust and valvetrain are concerned. The major difference is the size and shape of the "swirl port" combustion chambers.

If you want to use Magnum heads, I believe Hughes or Mancini sells a kit to change to oil through AMC style pushrods, and you have couple options for rocker arms, as the geometry is different ( closer to 1.6 than the 1.5 of earlier heads/rockers ). The exhaust will be close enough to bolt on the Magnum heads, but the intake bolts are different, so you will need to buy a Magnum specific manifold, or have your heads or manifold redrilled.

The only bad thing about the "...302"s are that they have smog ports, so that you need to drill ( slightly ) and tap with a 1/4 20 and screw in some allen set-screws to plug them up. But "...302"s are $$, while Magnums are $$$$, especially after spending more for a different or modified intake and valvetrain.

Check out this link on swapping to flat top KB pistons:

http://www.carcraft.com/howto/116_0401_318/index.html

They use the Magnum heads in this article, but mention the valves of the "302" being too small. Good luck on the $600 a pair Magnum heads, but you can buy a set of "...302"s from Aerohead with bigger valves for that price. There is newer article that was posted on BigBlockDart.com where someone had built a 400+ hp engine with swirl port heads and the stock hydraulic valvetrain ( also with th KB 167s ).
 
rumblefish360 said:
Well said.


post 51;
The small valve 360 had does very well on very pumped up 318's. They'll do OK with small cams on a mild build. But I would rather max what I have than crutch it.

post 52;

Best heads are subjective. Things like money in the pocket can dictate.
Magnum heads best OOTB cross over head.
302 best OE, "LA" head
360 head, best for on the cheap upgrade rather than porting the 302 to work best. Do realize you could potentaily be giving up 40+ pounds of torque with 360 heads.
Click to expand...

360 heads flow better, but you'll die on the street unless you set the engine for high rpm duty. It would be a better idea to put 318 heads on a low compression truck 360. You need compression and you need quench to get this for a street mill.
 
urchinhead said:
360 heads flow better, but you'll die on the street unless you set the engine for high rpm duty. It would be a better idea to put 318 heads on a low compression truck 360. You need compression and you need quench to get this for a street mill.
Click to expand...

Correct!!!!!! The 360 head has a large port for a mild 318 which will cause the air and fuel to be slow and hurt power.
Conversly the 318 head on a low comp 360 is a great idea for added power and torque on a low RPM engine. It'll speed up the air and fuel real nicely and burn better since it is being atomize finner. A 302 head will add a great quenched area to boot.

The RPM will have a lower ceiling, but it isn't a big deal for a truck/tow/work ride. If fact, I think it a good one.
 
so the 302 heads from areohead are bolt on and go with no modification besides pluging the smog ports correct?

if so i guess i found my heads
and ill get the 360 valves liek he did
 
I wouldnt let Aerohead near anything I own. But for a budget job, I guess they are a last resort.
 
Just a little “real world” experience you may be interested in. I had a 318 with ported J heads and a MP 284/.484 cam in my Barracuda years ago. I was told by a local Mopar “expert” that the 302 head was the way to go for even better performance…so I bought a set of 302’s and gave them a shot (nothing else was changed). The daily driver feel was much better with a definite increase in low end torque, but the high RPM horse power was just not there. I took the car the track and found that the 302’s made the car slow down by 6 tenths and 4 MPH in the quarter mile! After realizing that I just spent 500 bucks to slow my car down, I promptly removed the 302’s, and sold them to someone that was rebuilding a truck motor.

Just something to think about if you plan on going for more than just “daily driver” performance.
 
I am currently running Edelbrock heads on a built 360…MUCH faster than the 318 I ran years ago.
 
koo sounds intresting but im trying to keep it all original and rat rod the motor with parts from were ever to make more power
 
If that's your goal, then head over to pick-n-pull in San Jose and find a set of "...302s" on a Chrysler New Yorker ( '85 era ) and have them rebuilt from your local machine shop with the larger valves. I know that American Cylinder Head in Oakland can do it for you, but I'm not sure what shop in San Jose can - there should be a few. You may find a Magnum Motor in a truck if you're lucky, and it would be a good idea to pull the whole thing, 5.2 or 5.9L.
 
flyfish said:
Just a little “real world” experience you may be interested in. I had a 318 with ported J heads and a MP 284/.484 cam in my Barracuda years ago. I was told by a local Mopar “expert” that the 302 head was the way to go for even better performance…so I bought a set of 302’s and gave them a shot (nothing else was changed). The daily driver feel was much better with a definite increase in low end torque, but the high RPM horse power was just not there. I took the car the track and found that the 302’s made the car slow down by 6 tenths and 4 MPH in the quarter mile! After realizing that I just spent 500 bucks to slow my car down, I promptly removed the 302’s, and sold them to someone that was rebuilding a truck motor.

Just something to think about if you plan on going for more than just “daily driver” performance.
Click to expand...
flyfish you stated that you were running ported j heads and switched to the 302 heads. the performance dropped on the top end. what if anything was done to the 302 heads? were they as cast or were they treated to a port job or any kind of valve job as well? what intake was used on the car? if it was a intake geared for the 360 heads then there would have been a port matching problem for the 302 heads. these factors would cause the loss on the top end. i am just trying to get an apples to apples comparison here.....
 
The 302’s were freshly rebuilt with some light port work, bowls and gasket match done professionally. The intake was an Edelbrock Performer RPM. The J heads were home ported (my first time porting heads). The performance drop in the high RPM range was calculated via the “seat of the pants-O-meter”, same with the low end toque increase. The only real power comparison I have is from running my car at the track.

Getting the gasket match on the 302’s to work with the RPM intake took a bit of work; however, the skinny intake port “pinch” was still present…I literally could not fit my index finger in the intake port past the first knuckle.

I believe the cam and intake combo was better suited for the 360 heads, but I doubt that a smaller cam and intake with the 302 heads would have made more power…just my opinion.
 
Your compression is an overall figure based upon the volume of stroke compared to the volume above TDC, which includes volume of cylinder above TDC and the cc's of your combustion chamber. To increase compression ratio, you can either use taller pistons, reduce combustion chamber volume ( with different heads or milling ) or both, which is what most engine builders do. Your 318 is probably at about 8 or 8.5 to 1 compression, and by swapping to 302s, you might raise it to 8.75 or so at best.

Read this article ( they do a lot of milling of heads and block, as well as utilize taller pistons ):http://www.popularhotrodding.com/enginemasters/articles/mopar/0667em_mopar_318_engine/
 
koo thanks

a guys selling some 273 heads should i show any intrest or just continue with the 302s
 
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