318 cam change

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Ok. Well, I am not going to pull farggin teeth to get answers to questions that have been asked twelveteen times now, so to hell with it.
 
Steady driver said:
I thought us cars all came with automatics as standard and manuals were an option !
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No, it's backwards here back then.

Standard transmissions were manual and automatics were optional.

Automatics are not the more popular trans....


Y'all over there need to learn how to speak English..... :poke:
 
Very funny crazycuda and you are not wrong I've been to your country twice and no one gets my accent , still had a great time though .
 
Your current cylinder pressure is, IMO, almost, extremely important.
If its in the basement, a performance cam with a later-closing intake angle,will kill the off-the-line performance real quick, requiring other solutions like gears and loose convertors. You will keep throwing stuff at it, until you put pistons in it, or otherwise, bringing up the DCr.
On the other hand, the teener responds well to Long-tube headers, dual exhaust, and a small 4barrel. Of course 3.55s and a SG are pretty much mandatory.
If you're looking for snap, off-the-line, the oem cam is pretty good. She just needs to wind up in a hurry. Gears will do that for you.
But a better solution is to bring up the Dcr with a cam and piston swap. Those two go hand-in-hand, especially on a low-compression teener.The factory Dcr is probably less than 7.0/1, with cylinder pressure near 120. Thats in the basement.
A performance cam might put your Dcr close to 6.5 or less, and pressure down at 110, or less.Your teener will be very disappointing, off-the-line.
Unless you have a budget to fix the pressure, gears is the quickest, most cost-effective solution.
The cam and compression need to be engineered as a combination, at the time of rebuild/recondition, and pretty much married to eachother after that.
 
Hello aj if what I fit don't get low fifth teens at the run what u brung then I will have to do more! There's no more £ left at the moment . And the wife wants hollidays got to keep the old girl happy. About 25 years ago I had this set up but no headers and original valv springs in a 67 four door valiant it done 15 point 2 secs , that will do for now ( I hope) plus I got big back tyres now 😃 Pistons sounds expensive but thanks for your input it's all worth knowing.
 
Hello a j I parted with one thousand bucks plus shipping and tax last week ! I'm not made of money . I hope the force is there as well time will tell.
 
540Valiant said:
A guy gets on hers from another Country, and this is what he gets! Wow!
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I tell you what buddy. You look on here and tell me where he has YET to say what transmission he has.......yet he's been asked several times. I don't care WHERE you come from. That has ZERO to do with anything. If you want help, ANSWER the frikkin questions. Pretty simple. Or so I thought.

If you want sugar coating and pansies and fluffy bunnies and unicorns fartin rainbows, you're on the wrong site. If you want help, give the asked for info and you will get it.
 
Patience Rusty. There's a language , jargon and expertise barrier here. The guy is half way around the world also. When it's 11 pm. your time the guy is still asleep. (4 am. Wednesday)
 
Play nice guys. I can close the thread.
 
toolmanmike said:
Patience Rusty. There's a language , jargon and expertise barrier here. The guy is half way around the world also. When it's 11 pm. your time the guy is still asleep. (4 am. Wednesday)
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I guess you're right.......but I don't understand how anyone can misinterpret the question. Still.....my apologies.


So how bout this? Is it an automatic or a gearbox? If it doesn't get answered after that, I will just stay out.
 
LOL!!! Who knew that there could be such a langue barrier between English speaking folks. You guy's are the best free entertainment money can buy! Nonetheless the guy's here are a wealth of knowledge use patience and understanding to work through the question's they ask because there's always a method to the madness. Remember not everything is called the same thing on both sides of the pond! IE: Boot to them is the trunk to us. Or the Bonnet to them is the hood to us. And so forth and so on.
 
I gathered the bits together and this is it:

Steady driver said:
Edelbrock performer plus with lifters , will my standard valve springs be ok .

Also I just bought brand new performer inlet and four barrel carb true roller timing set and some used exhaust headers plus a new pro flow air filter.
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904, stock low C.R., stock 318 heads, unknown rear gear ratio.

Now we're gettin' somewhere, slowly....but we're moving. Without looking up the specs, in my opinion that's too much cam for the combo. It'll sound nice but you'll be eaten alive by your wife on her bicycle.

Yes the power steering gearbox is larger than the aluminum manual box, advantage you.
 
KosmicKuda said:
I gathered the bits together and this is it:



904, stock low C.R., stock 318 heads, unknown rear gear ratio.

Now we're gettin' somewhere, slowly....but we're moving. Without looking up the specs, in my opinion that's too much cam for the combo. It'll sound nice but you'll be eaten alive by your wife on her bicycle.

Yes the power steering gearbox is larger than the aluminum manual box, advantage you.
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I looked up the cam, and it's not too bad...

270°/270° advertised duration
204°/204° at .050"
.420"/.420" lift

The overlap should be around 16°

recommended non rotator locks springs are:

90 lbs at 1.650" installed height
178 lbs @ .375" open pressure


recommended rotator locks springs are:

90 lbs at 1.650" installed height
187 lbs @ .400" open pressure


Now referring to a 68 service manual (it's handy):

78-88 lbs at 1 11/16"
170-184 lbs @ 1 5/16"

So the stock spring rate should be close, but if they are the originals, they may have lost some of their pressure over the years and would be best to replace them with new ones...



Yes, that combo should work together... I would put fresh valve springs in to make sure that you don't drop a valve....


What year 318 is it? 67 or later? I'm not sure if the valiant came with a 318 in 67, it didn't go into the Barracuda until 68, so most likely it's not the original engine in his car...


View attachment Eddy Perf Plus Cam.jpg
 
Vin code says 273 This evening I lined up the timing cogs 6 top 12 bottom with front drivers piston at tdc but the rotor arm is at number three piston I think , anyway I removed the cam and the heads look like they have been skimed I noticed silver steel underside . Question. The rubbers inside the springs are nice condition but some are up some are down is normal ? ( I have not removed the heads) and stil not checked diff ratio the front is on axle stands . Question 2 I offered the old iron inlet up to a spare engine a old friend gave me (318) but the bolts are straight up type When did they change ? Also I still ain't checked the engine code. Fore a date yet sorry krazy cuda .
 
It doesnt really matter where the rotor is pointing, so long as its under the tower of whatever wire is going to the cylinder that you have indexed to TDC compression.
Now it customary to have the rotor pointing to the front intake manifold bolt, on the drivers side,because that locates the #1 plugwire tower(if so marked) in the proper orientation, and the vacuum advance can will also then be positioned in a way that makes timing changes easy. But like I said you can put it anywhere you want.
 
The 64 and older 273s had their intake bolts oriented at a different angle from all other small-block mopars. The mating surfaces are ground at the same angles.Its just the bolt angles that where different. The holes in the mismatched intakes can be ground out to fit the head angles, but the bolt-heads will not sit/clamp flat, and it will be impossible to properly torque them down. Many guys have done it anyway and seem to get away with it.

The old-style umbrella seals are a floating type and go up and down with the stems, and thats normal.

Everything I said in post #30 still applies, and is even more critical in an early 273-2bbl engine,because the compression in those was very low right from the factory.The piston swept volume is extremely small, relative to the chamber volume,and a late closing intake will kill the Dcr, which in turn will kill off-the-line giddy-up.
Then at the other end, the low compression will kill 3rd gear acceleration. The top of first will be ok, then it will lay down at the bottom of second gear, until the revs get back up, but since the cam is so small, you will have to shift before it gets going again,and third gear will be a disaster.The preceding dialog is as compared to a proper compression ratio increase.
Now, you can put some 3.55s in there, to help get it off the line, and that will also help with second gear, but as soon as you hit third gear it will go soft, and somewhere in the middle of 3rg gear it will give up.
A slightly higher stall TC will also help get you off the line, but with the very short powerband of that new cam, I wonder if it would be worth the cost of the install.
Whatever you do, do not increase the total combustion chamber size. That will turn that motor into a real turd.
But do as you wish, and prove me wrong.
 
AJ/FormS said:
It doesnt really matter where the rotor is pointing, so long as its under the tower of whatever wire is going to the cylinder that you have indexed to TDC compression.
Now it customary to have the rotor pointing to the front intake manifold bolt, on the drivers side,because that locates the #1 plugwire tower(if so marked) in the proper orientation, and the vacuum advance can will also then be positioned in a way that makes timing changes easy. But like I said you can put it anywhere you want.
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However, with the rotor, distributor drive gear being off from the factory location, indicates that there was some work done to this engine at some time. How much and how deep did they go is the question. Has it been rebuilt already once?
 
Steady driver said:
Vin code says 273 This evening I lined up the timing cogs 6 top 12 bottom with front drivers piston at tdc but the rotor arm is at number three piston I think , anyway I removed the cam and the heads look like they have been skimed I noticed silver steel underside . Question. The rubbers inside the springs are nice condition but some are up some are down is normal ? ( I have not removed the heads) and stil not checked diff ratio the front is on axle stands . Question 2 I offered the old iron inlet up to a spare engine a old friend gave me (318) but the bolts are straight up type When did they change ? Also I still ain't checked the engine code. Fore a date yet sorry krazy cuda .
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The rubbers on the springs that you refer to are called valve seals. Some of the factory seals will be up and some down. My head guy doesn't like that style and goes with the more positive locating seals that grab onto the valve guide. Sometimes the head needs to be machined for them to fit properly, but they last longer and work better. Here are some pictures of them:

View attachment Valve seal D01 B.jpg

View attachment Valve seal D02 B.jpg

View attachment Valve seal D04 B.jpg

View attachment Valve seal D05 B.jpg


Question 2: The straight up type intake manifold bolts (you call it inlet) that I think you are referring to are for the "magnum" series engine that started in 1992 and newer.

From 1964 to 1991 the small block is called the "LA" style small block.


So I saw that you said that your car was originally a 273 from the factory. I would check some numbers on the block to find out what vintage 318 it is. A quick check of the number on the front of the block just below the head may give you a clue. You may have to do some scraping and cleaning to see it, and sometimes they are not stamped deep and hard to read, but worth a shot until you can crawl under it from below and check the casting date on the side of the block...
 
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