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Demon_Dan

Demon_Dan

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when i built my .60 over 318 i heard the best thing to do was get the larger valve 360 heads ..,with that i had them ported and polished ... ive been hearing recently that having the more restrictive 318 heads might actually build torque , something that my engine is lacking quite a bit ...i mean.. i cant even leave a patch from a dead stop and gunning it..would love some input as i still have orig 318 heads laying in the garage ..thanks

Also are there any other sure ways to build torque?

Dan
 
You lost compression switching over to the 360 heads unless you're running aftermarket pistons or had them milled a good bit.
 
Does your bumpstick open the valves more than a stock 318 cam?

If your car won't even screach street radials from a dead stop on asphalt...you may need to double check everything.

My 73 Dart sport with mild 650 mech sec. equipped 318 would anniliate the right hind tire from a dead stop no sweat.

Torque? 318s have never been notorious for torque. Turbo(s) or Nitrous are known to increase torque exponentially squared.
 
How large of valves are in the heads? And how large are the runners? (in cc's) What camshaft are you running? Also what intake and carb?
Small engines are easily over cammed and carbed unless your racing them, the same applies to the heads. Every engine combo or instance needs a given set of heads to work to its fullest potential. Not every engine needs or wants a set of 360's, magnums' or eddy's. When building a engine choose parts and pieces that will work where you'll be driving most of the time and in the rpm range desired. This go's for everything in the engine from pistons to the intake and cam, carb, and ignition, type of crank and rods, etc. etc. If you need questions answered or just some clairity of direction then give me a call.
 
try the 4323302,or the 4323345s,are you running a 360 or 318 intake manifold? I got a set of 75 76 smog 360 heads 66 cc ,1.88 1.60s small runners,mill them, and I think they would work well on your 318 depending on your combo,im not into 318s to be honest with you ,I was told this by word of mouth from a guy I know. I dont need them.
 
scaned my info sheet i made up when my mechanic rattled off what we put in the engine..also the 360 heads were from aerohead racing , the description of them is as follows :

1968-1987 340-360 A-Engine Assem., 1.88 or 2.02X1.60 Stainless Valves, 67-70cc Open Chamber Design, .509" Lift Springs, 160cc Intake Port Volume

updatedemoninfo1.jpg


updateddemoninfo2.jpg
 
You'll like a ported 318 heads mentioned above over a 360 head, but I think your missing a few things that were left on the table.

Carb jetted well, stumbles off of idle or bogs, timing advanced some?
 
carb is out of the box ..Timing is advanced to 39 TOTAL advance ..no problems driving it ...its just a dog ..spoke to BJR Racing today on the phone ..thanks to him it appears ill be making a swap to a 318 head with some port work done.
 
Dan,
The timing is a bit too high, most engines that are open chambers don't like more than 35* and the 302's won't like more than 30* total at 2500 rpm's for street use. So you may be loseing some Tq. and HP there. But IMO you still won't get where you want to be without the head change.
 
ill make that timing change this weekend ..thanks...what ive decided to do because of money being tight is ill drive the car as best as i can until i can afford the body work/ head swap ,,thus pulling the engine for a good reason letting me swap heads and clean up the engine bay at the same time ...if its not to much to ask ..can i have a cpopy and paste able directions to print and hand to a machine shop guy with my 318 heads ...if its not to much trouble, thansk again friend !
 
BJR/ Demon dan - I dont want to be negative :sad7: - but with a :

2600 stall
3.5 gears
10.5:1 comp
280H cam
headers, 600cfm carb etc....

Surely this thing should be patching a little bit, even with the larger runner 360 heads?:dontknow:

I mean Im assuming the compression was calculated with the heads he is using? -

if so......Im thinking there's something weird going on:snakeman:...That thing should at least turn the tyres with that much advance in the ignition.....and Im suprised its not "pinging" its brain off.......

Dan- when you have the chance - get the cam degreed (even if your shop claims they did it) ......it smells of being seriously retarded....
 
Thanks Moparmal ..ill look into degreeing the cam ..in the mean time i looked at the casting number of the two sets of heads i have in the garage ..one is

4323302 - 318 Fast Burn 1985-86 1.78 1.50

the other pair are

2843675 - 273/318 1968-74 1.78 1.50

what ones are a better head ..does it matter?
 
Is it a dog throughout the whole rpm range or just on takeoff? If it's throughout the rpm range there's something wrong that can probably be corrected but I do agree those heads with that cam (which is fair sized) in a small cube engine isn't going to have great takeoff. Especially since the converter isn't very loose and the gears are somewhat tall. To make what you have now work it probably needs to get into the upper 3k rpm's on takeoff so you need a much looser converter and steeper gears.
 
2500 to 3500 seems to be the most powerful ...like passing on a highway in 3rd gear...but from a dead stop it feels like the engine is "trying" to pull the car ..hard to explain ..its like i can feel the resistance. when i mash the secondaries open ..there isnt a whole lot of shock and awe if you know what i mean..seems kind of sisssy ..like ..is that all ya got little guy
 
If it comes on good at 2500-3500 but then flattens out you could just be running lean. Have a look at those plugs and see what they look like. If you have a chassis dyno in your area that would be the best way to get it maximized. May cost a couple hundred bucks but it's well spent.

BTW: Is the distributor stock? If so the advance curve needs to be modified to limit total timing so you can run more initial timing and have it all come in faster.
 
running a 6A box with the MSD pro billet dist .. lite blue and lite silver springs and and 18 degree stop initial is set somewhere around 20 ,21 ..total is about 38 to 39 degrees
 
This is a long post - but there's abit to think about before swapping out the heads or cam -

These things need to be checked in stages - simplest first - atm we're all assuming heads or cam......

Im not disagreeing with Bobby or others - the heads would be hurting velocity - and as Bobby says, there may be some shrouding going on..he's the expert there......(and I am wondering about your comp - but we need specs)

.....but.......

A. - Check your plug leads! (some confuse a lumpy idle with a missing pot),

B. - MOST IMPORTANT - are you getting full secondaries at WOT? (Get someone to stand on the pedal and check the secs. with a torch- open the air door with a screw driver and look down the throats) ,

C. - COMPRESSION CHECK - Dont assume the rings have sealed - Check your static compression with a comp gauge - should have around 180 - 190psi for 10.5:1

Facts for you to consider -

1. - Your stall will be putting you close to the cams power band....(My 282S solid comes in around 2700 so yours should get lively even a little earlier) - so cam timing should not be an issue if installed correctly.

So the cam is not "too big"

2. - Tyre height has an effect on gearing - 3.5s is not real steep, I agree, but:

It takes very little torque to "flash" the converter , its what happens when it locks up that is important - ATM your converter should be allowing the engine to rev close to the cams power band - (its a 2800 TCI for chrissakes)
- it sounds like when the converter locks - theres no torque there - so theres a power drop off somewhere.

This is why we are suggesting heads, A/F and cam timing - the engine can rev OK, but its not producing the goods when under load. Make sme think its more than ONE thing......

3. - Your ignition timing at 21 static is almost identical to mine..its plenty to get the car to hurry up from "off idle"....again assuming the cam is "in sync" with the ignition timing.

For all these reasons..I suspect more than just heads......I reckon you've been pitched a "foul ball"...

ITs either:

A mechanical "set up" issue (see above)

OR

The combo (heads, cam timing, tyre height etc)

I just cant see your heads (as they are pretty "mild") affecting your launch that badly at 2700 rpm.....not unless they've had the heck hogged out of them......

However Id agree with Bobby - they're not ideal -

If the maintencance issues check out - then look at the other members suggestions -

1. - I agree- Swap the heads for the 302s and get BJR to pocket port them - your cam is pretty mild really.....

2. - I BETCHA your shop installed the cam "straight up"...get it degreed...


3. - I agree - hit the Dyno or BETTER STILL - dont pound the engine, get someone with a $300 A/F mixture meter and test it under driving conditions. Any good "tuner" shop should have one....

4. - Be aware - ypur ig. timing is NOT the problem - BUT - Get your dissy curved to be 34 all in MAX - Cylinder head temperature escalates dramatically with higher all in timing at high revolutions - it does your engine no favours. (Not to be confused with Vac advance that advances the timing at cruise revs)

Lastly -

Id like to know how tall your tyres are also - then I can run a comparison with mine - which is a VERY similar build re cam, carb, intake and heads) , and only 20 cubes more.

Also, what was the piston installed deck height? (above or below), and the piston part # , if you have this figure we can calculate the actual static comp.

I dont wish to sound bitchy - but you shouldnt ignore the possibility of a sloppy assembly(cam timing, comp calculations, valve seat sealing, poor ring seal)

Im guessing Bobby cant say this - due to "professional courtesies" , but its what springs to mind if the basic checks are OK.............
 
your running too much total dan, back it down to 34 or 35
 
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