318 heads. whats your route??

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I feel Im prety well qualified to pass judgement on the best route....

Up until recently, I was running a set of the most heavily ported and welded 318 heads you'd ever see, the runners were raised, ran 2.02 nailhead back cut valves and the intakes flowed 215 cfm.

These heads were specially done to increase air speed through the runner while maintaing a decent port volume. The guy that did them has a very good rep as a porter - (Pic below)

I ran a 13.46 with these, a 234 / .495 lift cam and 3.9 gears




Then I swapped to 587 360 heads with NO porting, and 1.96 tulip valves ..................and ran a 13.17.

Moral of the story - those teen heads had waaaaay more port work in them than any sane person would pay for (I got them off a guy who did them as an experiment in "velocity") ......and they still wouldnt hold up against some stock 360s........

For me its no contest IF you want max. HP for your combo - port volume is as important as air speed .......:-D
 
Moparmal,
215 cfm's with a 2.02, the port velocity had to have been down with that large of intake valve in a small port runner. This is why I say to run the 1.78 intake valve and we get the same amount of air flow infact a bit better at 228 cfm's, and I didn't weld nearly as much, and infact I didn't have to weld any on the 302 heads.
So far the best that the heads have done is 1.57 60' ft. and 7.53 1/8mi. @ 98 mph and at 3330 lbs. this is a stock 71 duster with a roll bar and driver.

In any case try to stay with the smallest valve per the head used as this will keep the velocity up to or at it's highest point easier. The reason the 360 heads ran faster is the intake valve was the smallest of both heads and port velocity was stronger in them. Now imagine if they had the original 1.88 valves in them they would be even better yet.

I've spent 20 years tell'in folks bigger valves, but this isn't so anymore as heads have gotten better in port shapes and chamber shapes the need for larger valves isn't as big a priority, infact the need is almost non-exisistant. About 5 years ago I went backwards as most would say and the performance went way up. Thanks to CAD development it made it easier to understand and learn, and see why.
 
I am building a 318 using magnum heads. The stock cam that came with the short block is .373/.400 and 240/248 according to Mopar info. With the magnum 1.6 ratio rockers, the lift changes to .387 and .427 and duration changes a little. The tranny is an a999 from a D150 with low gear set, and the rear axle is an 8.25 with 2.45 gears and suregrip. I also have available an a500 OD tranny and 3.55 gears as an option. Exhaust will be a large single pipe, no headers, for the carb, considering a small holley 4BBL or a thermoquad.
What kind of cam should I use to get a mild performance increase without sacrificing gas mileage much? I like lots of passing power/torque in second gear, when I need it, but racing is totally out of the question.
Is the stock cam good enough considering the much improved flow of magnum heads?
 
bill55az said:
I am building a 318 using magnum heads. The stock cam that came with the short block is .373/.400 and 240/248 according to Mopar info. With the magnum 1.6 ratio rockers, the lift changes to .387 and .427 and duration changes a little. The tranny is an a999 from a D150 with low gear set, and the rear axle is an 8.25 with 2.45 gears and suregrip. I also have available an a500 OD tranny and 3.55 gears as an option. Exhaust will be a large single pipe, no headers, for the carb, considering a small holley 4BBL or a thermoquad.
What kind of cam should I use to get a mild performance increase without sacrificing gas mileage much? I like lots of passing power/torque in second gear, when I need it, but racing is totally out of the question.
Is the stock cam good enough considering the much improved flow of magnum heads?
Click to expand...

This a good torquey cam: http://store.summitracing.com/partdetail.asp?part=SUM-6901&autoview=sku

Ran it in my 273 with good results.
 
bill55az said:
With the magnum 1.6 ratio rockers, the lift changes to .387 and .427 and duration changes a little.

What kind of cam should I use to get a mild performance increase without sacrificing gas mileage much? I like lots of passing power/torque in second gear, when I need it, but racing is totally out of the question.
Is the stock cam good enough considering the much improved flow of magnum heads?
Click to expand...

Bill, the duration doesn't change. The cam will open the valves at the same time everytime no matter the rocker ratio. It will just open them up quicker. The change in rocker ratio will add intenscity to the cam.

This cam is about as close to one step up from stock.
http://cranecams.com/?show=browsePa...=318 C.I.&partNumber=693901&partType=camshaft

Though I like the Crane equal to the sumitt cam better because of more lift. The sumitt cam is ground by Crane for and too Sumitt's specs.
http://cranecams.com/?show=browsePa...=318 C.I.&partNumber=693941&partType=camshaft

I've used this cam before and found it to make good power on the road even with a stock converter, 3.23/3.21 gears and stock tire diameters. Also in a search for mileage, I installed Rhoads lifters with this cam. It help with more vacuum and a slight help in low end torque. The cam is small and so the difference was also small. Noticable, but small.

Comp Cams also has a line that is ground for and to be used with exhaust manifolds. Home page here;
http://www.compcams.com/DefaultWide.asp

Catolog page here;
http://www.compcams.com/technical/Catalogs/106-07/26-37_228-229.pdf
Scroll down to Dual energy cams when you open the PDF.
 
BJR Racing said:
318Guy,
This is what I would do with the 318, I would get a set of KB 167 pistons, a set of roller rockers 1.5 and pushrods to give you a fully adjustable valvetrain. I would get a XE274 cam or the equiviliant from whom ever you choose. I would also use a M-1 intake with a 750VS carb. I would gasket match the 318 heads and bowl blend them useing the stock size valves and do a good valve job on the heads, use 1 5/8 hedders and good set of free flowing mufflers and you should be able to get 400 or so HP out of it. Just make sure when you get your cam that you get the correct springs and parts for the engine. This should give you a good start as to where to get headed to.
Click to expand...
whats the specs on the pistons and cam your sayin to get. im planning on roller rockers allready. would a 509/292 cam be sufficient? mopar performence parts. 199 bucks. are thos flat top pistons?
 
mullinax95 said:
There is no one putting you down. It is only a suggestion that you switch to a 360 or big block. If all you want is 350 hp area then the best thing to do is keep the 318. Yes you can even get 400 hp from the 318 but don't forget about torque. The 318 will not make as much torque. I and others want more torque. Torque = fun!

Why rev a motor 8 grand when you can get the same amount of hp/tq from less RPM from a 360 or big block?

It's not a faggish way of doing anything. If so my friend there is sure a lot of **** here at FABO. I've seen countless members remove their 273,318 and go with the 360, stroked 360 or big block. Its the smart thing to do rather than spend the same amount of money on small bore, short stroke 318.
Click to expand...
i dont have a **** load of money to go with. yet i could still make a 384 stroker with a 4 inch crank. theres my torque. and a hell of alot closer to 350hp
 
Moparmal said:
I feel Im prety well qualified to pass judgement on the best route....

Up until recently, I was running a set of the most heavily ported and welded 318 heads you'd ever see, the runners were raised, ran 2.02 nailhead back cut valves and the intakes flowed 215 cfm.

These heads were specially done to increase air speed through the runner while maintaing a decent port volume. The guy that did them has a very good rep as a porter - (Pic below)

I ran a 13.46 with these, a 234 / .495 lift cam and 3.9 gears




Then I swapped to 587 360 heads with NO porting, and 1.96 tulip valves ..................and ran a 13.17.

Moral of the story - those teen heads had waaaaay more port work in them than any sane person would pay for (I got them off a guy who did them as an experiment in "velocity") ......and they still wouldnt hold up against some stock 360s........

For me its no contest IF you want max. HP for your combo - port volume is as important as air speed .......:-D
Click to expand...
the heads im puttin on it are redone 360 heads. 1.88 1.60 valves. soon to be ported & polished. maybe some roller rockers later on. 509/292 cam. maybe 484/284. bout the same price. i gotta find a 750 carb
 
What would be your cam size if you used the .441/.441 cam with the 1.6 rockers?

I forgot how to figure that.
 
Mopar318Guy,
The pistons are flat tops and will get you close to 0 deck and the cam from mopar that I would use would be the .484/284 cam as you've said.
 
Mopar318Guy said:
so 509/292 would make less power then the 484/284?
Click to expand...

A 509 would likely make marginally more peak power, but they have a history of really suffering compared to the 484 from about 500 rpm below peak and down. The 484 usually makes more power where you need it for a street driver.
 
BJR Racing said:
Moparmal,
215 cfm's with a 2.02, the port velocity had to have been down with that large of intake valve in a small port runner. .
Click to expand...

In fairness Bobby, I should say that the guy that ported the heads didnt machine the valve seats...the machine shop stuffed up - we were going to use a 1.96 intake.

Sh** Happens I guess!
 
Believe me I know, all it takes some times is a distraction and the thought process go's out the window. This is why the valve job should be close to finish before and then the port work done so all thats needed is a touch up of the seats. And in all fairness the shop that cut the seats should have installed new seats to use the valves that you were going to go with to start with. Not just cut them and then say oh well we F'd up and you have to use 2.02 valves now.
 
BJR Racing said:
Believe me I know, all it takes some times is a distraction and the thought process go's out the window. This is why the valve job should be close to finish before and then the port work done so all thats needed is a touch up of the seats. And in all fairness the shop that cut the seats should have installed new seats to use the valves that you were going to go with to start with. Not just cut them and then say oh well we F'd up and you have to use 2.02 valves now.
Click to expand...
yea. so 484/284 cam. and get the heads (360) i have port polished. im lookin into an air gap intake. i have headers. and im planning on roller lifters and rockers, less friction. what do you think?
 
You cant run roller lifters without the roller cam, the cam that you have listed is a flat tappet hyd. cam. They arent compatiable.
 
I would run the air gap over the M1 and run a 650 holley and you will be happy. 318's RULE!
 
That sounds like a huge F'n cam. But go with it if thats what they say.

There is nothing wrong with a 318! ask others, i defend them till death, I do agree with the attiude though, being new thats not the way to come off, we had someone here like that before. With that said, i also understand why you would be sick of everyone telling you to use a 360. They make good points, and you should take it with a grain of salt. Remeber everything you do to a teen, you can do with a 360, so alot of the advice can be used both ways. Keep the teen! They are great motors, I will add though, the cam i think is to radical, maybe i missed something though. 360 heads, airgap, i would go 600-650 carb and your dreams of 350hp WILL BE CRUSHED! 400 EASY. AS for rev the teen to 8 grand? I dont think so, your assemble wont even see that. You would have to go with lighter rods and crank and have it all balanced. 6000-6500 maybe but you power and everything else would drop after that. Build what you got, remember all it would take is a $400 nos kit and youd hit 500+. go with a moly ring with the KB167's and make sure you or who ever does the work to gap to KB's spacific instrution on ring gap for a nitrous setup. Even if you never get the juice, you will be set up for it.
 
76318dart said:
I would run the air gap over the M1 and run a 650 holley and you will be happy. 318's RULE!
Click to expand...

I agree on the air gap intake..rev a 318 to 8 grand.. ya' maybe once then it'll come apart..318s rule!..lol..thats a good one..
 
Bar none, built right a 318 will run. Just not as torquey as 340/360, but I think with minor to moderate mods all the way around you could easily see 350HP+, so go the way you're going and give us some feedback as to how she runs.
 
73DartSport said:
Bar none, built right a 318 will run. Just not as torquey as 340/360, but I think with minor to moderate mods all the way around you could easily see 350HP+, so go the way you're going and give us some feedback as to how she runs.
Click to expand...
im bout to pull the motor tomarro. just got me a job. ill be gettin some money. 350 bucks for the rebuild kit 200 for the cam and 250 for the intake. already got 360 heads. port and polishing them for 125 bucks. so all together i think it should be pretty good. i dont know if theres any dynos i nthe area but if there is itll be dynod and proven. probly june or so when it all comes together.
 
Stick with the teen M318G. Nothing wrong with them.

Hey Mal, you forgot to tell everyone your running a 360 crank in that teen of yours...so youve got 350 cubes!!:bootysha: Oops, they werent spose to know??. :thebirdm:

Little story from the old days (early 80s).

A mate had a 76 Oz Charger (a bod) with a smogga 60 in it.
He put a Torker manifold on, 750 vac Holley, a Hemi grind DC cam and a set of headers, but left the stock heads, verter and gears 2.77s.

I had a 77 Oz Charger, with a stock smog teen in it (no elb), with a worn out 360 2bbl cam, std Carter bbs on a 2bbl manifold, headers and a 2.92 gear.

His car was rumpy, a 360, and sounded the goods. Mine was just a stocky teen.:-D

From the line, I could jump a car length ahead everytime and he couldnt catch me. From a rolling start (40mph) it was neck and neck with me maybe just inching away.

Lesson learned when your young.

Build the package as a whole combo. Dont overcam, unless you got the heads/compresh/gears to match. AND 318s Kick A*s.
Its always fun to hear the little teens windout fast in low gear too.
The 360s almost feel sluggish...other than the torque of course.

Stick with the teen and have fun.
 
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