Cams for 318's

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My dad's 86 van was same way. Block was capable of being a roller cam but was not.
On the 360-2 cam in a 318
I have done this, and along with a magnum head swap it made a HUGE improvement.
Yeah I know, magnum head conversion means 1.6 rockers vs 1.5s but I think I am about to try it on a 318 that's getting 302 heads, with stock 1.5s. if it makes 1/2 of the difference that I had in the one I did the magnum heads on I'll be happy.
 
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My dad's 86 can was same way. Block was capable of being a roller cam but was not.
On the 360-2 cam in a 318
I have done this, and along with a magnum head swap it made a HUGE improvement.
Yeah I know, magnum head conversion means 1.6 rockers vs 1.5s but I think I am about to try it on a 318 that's getting 302 heads, with stock 1.5s. if it makes 1/2 of the difference that I had in the one I did the magnum heads on I'll be happy.
Let us know how good that works. Magnum's flow a little better than the LA heads, bigger lift because of the rockers, and a efficient closed chamber. The 302's are close but with 1.5 shaft rockers. The early 273 heads are quite close sporting a closed chamber as well. With a little grinding, those early heads can be made to work quite well.
 
But I have what I have. I haven't seen a set of 273 heads,in years
 
But I have what I have. I haven't seen a set of 273 heads,in years
Here's my 273 heads. They are a #178 and #234. One was replaced along the way along with a newer rod bearing. I suspect there was a collision at some point. LOL The last one is a #920 with a original steel shim head gasket.

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stock head gasket on 920.jpg
 
Hey guys. Humor me for a minute.
Do me a favor. Little homework assignment
Look in any 70s FSM and find the specs for the 360-2 stock cam.
Hang onto that for a minute.
NOW go look up all the same specs for a COMP 252 for our small blocks.

You will see that they are IDENTICAL. In every way possible except 1.
One has an overall lift of 0.410. both intake and exhaust. The other has a lift of 0.425 on both valves.
For the difference in cost of the melling stock replacement I can buy 2 sets for less than 1 COMP 252. Big enough difference that losing a while 0.015 in overall lift doesn't mean a hill of beans.
 
Hey guys. Humor me for a minute.
Do me a favor. Little homework assignment
Look in any 70s FSM and find the specs for the 360-2 stock cam.
Hang onto that for a minute.
NOW go look up all the same specs for a COMP 252 for our small blocks.

You will see that they are IDENTICAL. In every way possible except 1.
One has an overall lift of 0.410. both intake and exhaust. The other has a lift of 0.425 on both valves.
For the difference in cost of the melling stock replacement I can buy 2 sets for less than 1 COMP 252. Big enough difference that losing a while 0.015 in overall lift doesn't mean a hill of beans.
Melling offers some nice cams. Pretty close to the oem grinds. Elgin and Sealed Power too.
 

So I made this video for toolmanmike of my 318.Crappy video but we were after the sound at idle.I haven't had the chance to drive it yet on the streets.It will be awhile.
1970 teen stock heads and bottom end.
Comp cam #20-212-2 Grind #CRS 268H-10 Compatible valve springs.
Lift both I&E .454 Duration @ .050 both I&E 218. Lobe Separation 110 installed.
Headers 2 1/2'' duals no crossover and no tailpipes ending at rear housing.
Jegs 2 1/2'' Turbo Mufflers #300010
Idle set at 750ish RPM
 
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Doesn't the comp HE/XE line have faster ramp rates?

...and .015 is a noticeable difference in lift.
 
A lot of good info here and I'm still trying to read all of them, but this feed reminded me of a really good video I watched. The guy is mostly a Chevy LS guy but the information in the video is platform agnostic and the information is great for a newb like me:

 
F@#k the chevy and especially the LS.
I am so damn sick and tired of hearing about them. There's reasons why I have never owned anything else besides a Dodge.
 
A lot of good info here and I'm still trying to read all of them, but this feed reminded me of a really good video I watched. The guy is mostly a Chevy LS guy but the information in the video is platform agnostic and the information is great for a newb like me:


He does all brands. Some of his latest vids are Fords. He has done Buicks, Olds, and even a 440.
 
F@#k the chevy and especially the LS.
I am so damn sick and tired of hearing about them. There's reasons why I have never owned anything else besides a Dodge.

That's why I preferenced it saying the information is platform agnostic, meaning it's not just LS info, it's cam info
 
Well, I'm late to this conversation, but have spent the last two days reading through all of it. My question is: what does everyone think of the stock 360 2bbl cam in a 318? I didn't see anyone mention it on here. It has a little more duration and lift than the stock 318 cam. The overlap is a little more too. Looks like the intake closes 6 degrees later than the 318 cam per my 1973 Plymouth and Chrysler service manual. It seems that if it worked that great then Chrysler would have put the same cam in both engines. I have a 1986 318 2bbl in a D150 that has a flat lobe on the cam. It has the 302 heads so it has a little more compression than the earlier models. If I can get a little more performance from that 360 cam I would buy it vs. buying a stock 318 cam. I like the spec's on the Lunati 10200700 and Howards CL711381-10 cams though replacing the valve springs is out of my budget. I'm hoping that someone here has already done this and can tell me if they like it or not. View attachment 1715641889

Just wanted to update anyone who's interested. I went ahead and bought a Melling version of the 360 2bbl. cam and a set of their lifters and installed it. I got it all back together and running. It idles smooth with about 18.5" of vacuum. BTW, I received one defective lifter in the set of 16 from Melling. It measured 0.906" diameter instead of 0.904". I'm glad I bought everything from a local parts store instead of online. I had a replacement waiting for me the next morning. If I would have bought it online I would have been waiting about a week for a replacement. Cranking compression runs anywhere from 145 psi to 155 psi between the cylinders. I checked the compression before I pulled the old cam out and it was about the same except for #8 cylinder which had no exhaust lobe left on it and was at 160 psi. The bad cam lobe made it pop back through the intake anytime you accelerated the engine. It also had the intake pushrod bent at about a 45 degree angle on #8 cylinder. The lobe was OK, the lifter wasn't sticking and the valve wasn't stuck so I'm thinking the backfiring caused that? I've had it running on the new cam for about an hour with no other issues. The #7 cylinder exhaust lobe was worn a little too. The rest looked OK. It sounds great out the exhaust too. One last thing I noticed was there was a lot of slack in the old timing chain, but the plastic gears hadn't broken off yet. I figured it was just stretch in the chain so I replaced it with a good used double roller set off of my 340. This set wasn't loose on my 340 but when I put it on the 318, I still had some slack in the chain. The cam to crank center line on this 318 must be a little short. I haven't seen that before. This engine appears to be all original to the truck and shows no sign of rebuilding. Every part I took off of it had a Chrysler part number on it.
 
On the street, on the cheap I have run the Summit .444/.444 manual trans cam in my 318. It ran pretty good.. I am fixing to try the same cam in my 340.
 
On the street, on the cheap I have run the Summit .444/.444 manual trans cam in my 318. It ran pretty good.. I am fixing to try the same cam in my 340.
Is it a little doggy out of the chute but turns on at 3 grand or so?
 
Is it a little doggy out of the chute but turns on at 3 grand or so?
Yes,it is definitely there once the rpms are up or at a roll . I liked it in my 318 for street use. I think Summit calls it a "classic" grind now. I may try one of their moreaggressive "race grinds" . My car isn't really set up for race though. I am mostly stock on the exhaust side. Manifolds and stock as urate exhaust.
 
It's far too easy to overcam your engine. Get your best cam choice and then choose the next one smaller. You'll be happier.
 
At the risk of repeating old information; I gotta say this;
If you marry your whatever cam to a decent DCR, you will never go away unhappy.
Wyrmrider preaches duration from .200 to .200 and whenever you can, you need to keep that in mind. If you start from the .200 numbers and work backwards, you will find the Scr you need, to achieve that "decent" DCr.

If you leave your Scr alone as delivered from the factory,and install a bigger cam with a LATER closing intake angle, this is guaranteed to be a low-rpm disappointment. And you will have to bandaid your combo with a higher stall TC, and sometimes, more rear gear.
If this sounds like a foreign language let me walk you thru a few examples.
Lets take an 8.0 advertised Smog-era 318LA, that has a stock HFT cam advertised at 240/248/112 (IIRC), Lets work out the whole picture, I get;
240/129/123/248/20, Ica of 51* and effective overlap of 18*
(intake/comp,power/exhaust/overlap)
Ok so lets install this cam and set the installed centerline to 111*, and at 800 ft elevation, the Wallace says;
Static compression ratio of 8:1.
Effective stroke is 2.84 inches.
Your dynamic compression ratio is 7.00:1 .
Your dynamic cranking pressure is 133.00 PSI.
V/P (Volume to Pressure Index) is ..............................109
read about VP here V/P Index Calculation
In a nutshell VP is a measure of sub 3200 performance that is sorta relatively comparable across all sizes of engines. So a 318 at 109 is gonna feel like a 360 at 109, etc.
Ok so now, you already know what a 318 at 109 feels like, and you certainly don't want your 318 to be any doggier than that, right.
So with no other changes, say you install a Mopar 268 cam with an Ica of 64*; and what happens? I'll tell you, the VP drops like a rock to;

Static compression ratio of 8:1.
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 6.43:1 .
Your dynamic cranking pressure is 118.36 PSI.
V/P (Volume to Pressure Index) is ............................... 88
that is slanty territory right there. If you have a manual trans, you will need 109/88=plus 24% more rear gear to break even in performance at below possibly 3500rpm!
With an automatic, you will have to jump up the stall, possibly also 24%.
Why did this happen?
Well look at the Dcrs, it dropped from 7.0 to 6.43.. Let me jump up the Scr until I get back that 7.0 with the 268 cam.

Static compression ratio of 8.75:1.
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 7.01:1 .
Your dynamic cranking pressure is 133.26 PSI.
V/P (Volume to Pressure Index) is ................ 99
Now you see that the VP has climbed up a bit, but still is weaker than the stock 318.Also the pressure is just 133 so we have lots of room (up to 160psi say, with open chamber heads) to pump it up. Lets take it to 155, so we can burn cheap gas.

Static compression ratio of 9.82:1.
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 7.84:1 .
Your dynamic cranking pressure is 155.03 PSI.
V/P (Volume to Pressure Index) is............................... 115
There ya go; 155psi, and a Dcr of 7.84, and a VP of 115 which is now 115/109= plus 5.5% higher than the stock 318. NOW you got yourself something to work with.

But hang on a sec, I specified an Ica of 64* on that 268 cam , cuz that is ABOUT what comes on the Mopar 340 cam. And the .050 for that is 228/235/114.... and a 228 cam might powerpeak at about 5100rpm, which with 2.76s is maybe 70mph at the top of first gear..... is that what you want?
Furthermore, if you could make the same power at a lower rpm, would you like that? This is where Wormrider's 200/200 spec come in.
Furthermore, if you could get the same power with less advertised duration, would you like that?
I know I would. This where you toss the HFT cam away and get yourself a Solid.
Lets say the fat 200s allow a 263 cam, and lets say the swap to a solid allows a 258 cam. I mean I'm just tossing numbers out there.
So this solid-lifter cam now, lets say it has the following advertised specs
258/123/121/262/44/42Effective and Ica of 57*
This is a whole different build now.

First, lets put the Scr back to 8.0, and I get
Static compression ratio of 8:1.

Effective stroke is 2.72 inches.
Your dynamic compression ratio is 6.74:1 .
Your dynamic cranking pressure is 126.29 PSI.
V/P (Volume to Pressure Index) is ..........................99
Hey that's looking pretty good, lets bump the pressure up again to 155
Static compression ratio of 9.35:1.

Effective stroke is 2.72 inches.
Your dynamic compression ratio is 7.85:1 .
Your dynamic cranking pressure is 155.29 PSI.
V/P (Volume to Pressure Index) is .................... 122
Wow lookit that the V/P is up to 122, And the .050 will be down some, bringing the power peak down with it, but because the 200/200 is fat, you may not lose any power at all! This is the point Wrmrider is trying to make.
With a VP now of 122, you can use whatever stall and gears were behind the 318 but now with INCREASED sub-3000rpm performance.
And finally; it may be a bit cheaper to increase the 318s Scr to 9.35 versus 9.82

Just for the heckuvit, lets install closed chambers on that 318, decrease the Q to .040 or less, and pump it up to 165psi
Static compression ratio of 9.8:1.

Effective stroke is 2.72 inches.
Your dynamic compression ratio is 8.22:1 .
Your dynamic cranking pressure is 165.15 PSI.
V/P (Volume to Pressure Index) is ............................129
wouldja lookit that VP now 129!, that is 129/109= plus 18% stronger than stock. The penalty is that you will have to run 91gas or better at WOT. But think about it;
18% better VP is like adding 18% rear gear, say from 2.76s to 3.23s, or from 3.23s to 3.73s; to the stock 318. Yur gonna notice that punch.

To be clear; this is an example of what you can do;
and specifically with those very nice pages of data that Wrmrider is publishing, as regards the 200/200 numbers.
This is in no way a recommended build. And personally, I would never install any 268 cam in a 318, with open chamber iron heads, for street use, nor any 114LSA cam. And the reason is this; with just 107ish degrees of power extraction, the Mopar 268/276/114 sucks gas bigtime. Or rather, there is a lot of energy still in the expanding exhaust gasses when the valve pops open; energy that could have been used to propel the vehicle, but that all goes to making noise instead.

OK for the one guy who wants to know; what about alloy heads on a 318 with a 268 cam. Here is what I would do
Static compression ratio of 11.2:1.

Ica of 64*/ still 800ft
Effective stroke is 2.57 inches.
Your dynamic compression ratio is 8.91:1 .
Your dynamic cranking pressure is 183.78 PSI.
V/P (Volume to Pressure Index) is 136
I have a manual trans, with NO TC to help get off the line. So, for me, VP of 140 is where the fun begins. missed it by that much,lol.
See what I mean about the 268 cam? the Ica of 64* is just too much for a 318, even at 11.2Scr!

>Also remember that VP importance diminishes with rpm, and a 3000stall just about nullifies it. So, I mean, if you cannot reasonably get to the Scrs that I have indicated in this study,remember that a high stall gets you past the importance of VP.
>But if you have a manual trans, most of the time, you will be operating in that sub 3000/3500 rpm range, And EVERY SINGLE TIME YOU START OUT from zero mph, VP will be very important.
> also remember that at WOT,as the rpm rises,your cylinders are gonna start filling to a denser air charge, and at some point, between maybe 3000 and 4000 rpm, you may have to be careful with your PowerTiming to avoid detonation, on account of that 11.2Scr is getting real close to the line.> but again, I wouldn't run that 268 cam in a 318 on the street, period. I would sooner get me a bigger engine, to run a smaller cam, for the same WOT power AND a stronger bottom end. Oh wait; that is what I did,lol. Here is 360 with a 360 2bbl cam and 9.5Scr

Static compression ratio of 9.5:1.
Effective stroke is 2.95 inches.
Your dynamic compression ratio is 8.00:1 .
Your dynamic cranking pressure is 159.28 PSI.
V/P (Volume to Pressure Index) is ...........................142
See that? VP of 142 without hardly trying.I mean all I did was pump it up to 9.5Scr/8.00Dcr. And the power peak is already in a good place, say 4500@39mph in 2.45 first gear with 3.23s. A footstomp should get both tires spinning.

Happy HotRodding

Edit
Oh but you wanna know about the 268 in the 360?
First at 8.0Scr
Static compression ratio of 8:1.
Effective stroke is 2.79 inches.
Your dynamic compression ratio is 6.46:1 .
Your dynamic cranking pressure is 119.12 PSI.
V/P (Volume to Pressure Index) is ........................100
Not too impressive, the bottom end is weak

optimized for Iron heads and 89 gas

Static compression ratio of 10:1.
Effective stroke is 2.79 inches.
Your dynamic compression ratio is 8.01:1 .
Your dynamic cranking pressure is 159.55 PSI.
V/P (Volume to Pressure Index) is ......................134
Wow, lookit that jump in VP, impressive

And optimized for alloy heads and 87E10
Static compression ratio of 11.2:1.

Effective stroke is 2.79 inches.
Your dynamic compression ratio is 8.95:1 .
Your dynamic cranking pressure is 184.87 PSI.
V/P (Volume to Pressure Index) is .......................156
there ya go; feels like a 440Magnum of yesteryear...... up to say 3500rpm . Vp of 156 is actually borderline excessive. That's about what my 367runs and 295s don't stand a chance. But it is so sweet to take off with; basically I just blip the throttle a lil in Neutral, then let the flywheel launch me with a dump it and go kindof deal.
 
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Never heard of such a thing??? Way too many variables involved to make a statement like that.
My completely stock 360 mag with Hughes valve springs and setup has only .020 retainer to guide clearance that’s with no block decking and stock head gasket. You better check it!!
 
I've asked earlier about a cam for one of my 318s (I'm definitely not a 318 hater) and all seem "too big" for what I'm wanting..... I have a COMP 260 that I'm thinking of putting into a 56k original mile 318 in a 78 B body Fury 2door along with a set of fresh from the machine shop, '302 heads..... but I wasn't getting replies that made sense so I have just been "watching" what they tell everyone else since. I don't understand VP and such either. I just want something to wake up a 3 season daily driver a bit....
I'm NOT rebuilding the whole motor.... and I'm NOT "dumping the 318 for a 360".
I once put a Melling "stock replacement" 360-2bbl cam in a 318 with an EQ Magnum head conversion and a Performer intake and carb in a 3/4 ton truck, (I didn't rebuild that bottom end either) and was pleasantly surprised by the results of that build up. this was back in '09 or 10, truck still runs, (I might be reacquiring it from the guy I sold it to, now it needs body work)
 
that one doesn't seem "too" crazy from what I know about cams....
I was looking at either........ putting in the COMP 260 I have or (I think the other name is a COMP XE250, has a split intake/exh duration. It's COMP 20-220-3.
or go back with another stock replacement Melling 360-2bbl cam.
 
Hello everyone!

I have been trying to find information about the Mopar camshaft that was used in rally cars in the 1960s. It is mentioned, for example, in this classification book.

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Is the manufacturer Racer Brown or some other manufacturer? Can anyone tell me something?
 
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