318 driver - cam change or not?

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RustyRatRod said:
Yes. I have used the cam I recommended in a 318 with Edelbrock Performer, Holley 600 and headers. I like it. Of course the resident guru shut it down so surely it was a dog.
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Used that cam a bunch in different engines/makes and it works!. I just like to "fudge" a little more with the new cams but if I had the grind you mention on the shelf it would go in.
 
lead69 said:
Used that cam a bunch in different engines/makes and it works!. I just like to "fudge" a little more with the new cams but if I had the grind you mention on the shelf it would go in.
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It's probably all he'll ever need. There's a reason every single camshaft maker has a version of that grind, and it's not because some forum guru says it doesn't work. lol
 
The reason is CHEAP buy from the lowest cost vendor
advancing the 204-214 cam makes the exhaust open too early- right rj

slantsix64 and I were suggesting based on not changing the rear end and converter- the route suggested by RJ is also valid and would be needed with the cams listed below
see from 2002 and still valid
anyone think cam deigns have not improved over the last 50 years?
360 towing engine - Moparchat - Home of MOPAR enthusiasts worldwide!
they had a popularity contest with these cams
#1-206/206 .425/,425 lift 110 seperation...Comp cams
#2-206/212 .432/.444 lift 110 seperation...Comp cams
#3-204/214 .429/.452 lift 112 seperation...Crane Cams
#4-210/210 .441/.441 lift 110 seperation...Lunati
#5-204/214 .420/.442 lift 112 seperation...Summit (Elgin et all) missing is the old Cam Dynamics and others

a comment
RF is right on the money,I wouldn't run any of these cams,
the most awesome RV stump pulling cam is the MP P4452757,this thing will amaze you its .410/.425 and 248/256 on a 110 lobe sep,I run it in all RV 360s and it out performs them all,many people will put down MP cams because of their age of design,this cam hasn't been around that long and few have ever tried it.............PRO..........

Pro are you refering to the
P4452757 .410"/.425" lift . 248/256 dur.
I will be installing one in my 72 Satellite 318 4 BBL.
I have heard this cam will turn a 318 or 360 into a Stump Puller.
+ 20 to 25 lbs torque over stock.

451mopar Im not sure what the LSA is on that stock cam you mentioned but Ill tell you this my 85 ramcharger has a 360 4 bbl and this mp cam picked up an honest 30hp over the stocker, it'll now spin the tires effortlessly,the only other mod was headers which were there before the cam change,it redlined at 4400 before cam swap and redlines at 4800 after...........PRO..........

a summit cam? say it isnt so,well weve all been there actually its a chevy grind on a mopar stick,Ive not tried the #2 cam but that mp cam is nothing short of amazing,.........PRO...

RRR wrote in 2015
IMO, while the Comp 268 is a great cam, it is too big for this application. I would look for something close to the old 204-214 @ .050 or there abouts.

Agree with toolman mike
Leave it alone. You can do much of a cam change on a 318 without changing everything else. The 4 barrel and intake and a smooth flowing exhaust does the most for a stock 318.

The cams slant suggested are much better than the MP cams and the MP cams were lot better than the ones on the 2002 list

Op can use those without making all the other changes, compression, gears, converter
if you pull the heads do a good multi angle valve job and pocket port
 
Garrett Ellison said:
I recommend changing up to an 8-1/4 before going any farther, unless you have a sure grip in your 7-1/4. You may find your style of driving becomes a lot more spirited with the extra power.
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Thanks for all the replies. I think I will be more likely to open it up with it running better. It occurred to me that basically what I am wanting to do is what the factory would have done if they had offered a performance 318. I'm sure the factory would have included at least 3.23 gears as several have said.
69cudaownr said:
I had what you had right back to the 2.76 gears. Short answer, in my opinion "yes" a mild cam is a good addition. One reason you may not have thought of is..............if you're the type of guy to second guess a decision. You'll continually second guess "not installing" the cam when you had the chance.
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Garrett Ellison said:
^^^THIS, all day and night long^^^ every time I’ve helped change an intake or do it without swapping the cam I always say after it’s done “Well, it’s a lot better, but had we put this or that cam in it would have gained that much more again.” It’s all about properly matched components. And as Mike says, 2.94 to 3.21 gears in a stronger rear end will make your car a lot more fun to drive.
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I'm definitely the guy that will second guess not doing it when it was easy so these are very good points.

AJ, your gearing and TM points make a lot of good sense. If at some point, I put in a 2600-2800 stall convertor, would I need to run an additional trans. cooler? Will I see more rpm at cruising speed or is the increased stall mostly noticed at high-load low speed.

Looks like I need to start looking for another rearend. Do you guys know what my chances are of finding an F,M,J 8 1/4 with
3.21 gears? I've always hated the way the back tires are tucked under the wheelwells on the Duster so I'd like to take care of
that and get gears at the same time.

Sorry for the book and thanks again to all for the help. This site is really cool.
 
1973dust said:
AJ, your gearing and TM points make a lot of good sense. If at some point, I put in a 2600-2800 stall convertor, would I need to run an additional trans. cooler?"Will I see more rpm at cruising speed or is the increased stall mostly noticed at high-load low speed."
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As to the cooler, that is always a good idea, but whether you need it or nor is gonna depend on your final gearing and usage.
The stall speed depends on the input torque, versus the load and if the tires are spinning or not. There will be about three times you will notice it
1) everytime you take off from zero mph, depending on how hard you are taking off
2) everytime the engine rpm has fallen to lower than the stall, as in you are slowing down but the trans has not yet downshifted, and then you get back on the throttle
3) anytime your cruise rpm is lower than the stall, and you begin to accelerate..

Lets look at #3 first.
With a small engine, you are kindof gonna have to make up your mind whether you value low speed performance, versus hiway cruising. For cruising, as you know, the 318 likes; 2.76s to 3.23s at most, depending on your idea of comfortable cruising, and the actual cruising speed. Personally I like to cruise at 65= 2200. My combo is happy there and the pipes are singing a nice tune. With 27" tires and a loc-up trans, this requires a rear gear of 2.60. Your 2.76s and 27s would get you 65=2230 at zero-slip, which is very nice.
After that, every 1% higher gearing will increase the cruise rpm by the same 1% . So, 3.23s are 3.23/2.76= plus 17% ,and your cruise rpm at 65mph will therefore increase by the same 17%, so 2610. This is the penalty you pay for small-engine performance.
However,for performance driving with a small engine, 3.23s are entry level gearing. So you have to be careful in selecting the cam versus your cylinder pressure, cuz you can very quickly make a lazy combo out of it. And this is where the Convertor comes in. It can make or break your combo.
That is to say, if you choose a too-big cam, for it's increased power,that may not begin until well after 3500rpm, that will destroy your power under that 3500rpm. So you likely wouldn't want to be powering thru there, so you might choose a 3500 TC so the engine never gets stuck in that lazy place. But with the entry-level 3.23 gearing yur gonna be in first gear until 50 to 55 mph.Again, that is the penalty for using 3.23s.
But say you choose a faster rate of lift cam than you now have, that might be a size, or a size and a half, bigger at .050 . That's smart shopping. So with this thinking, you will not lose any low-rpm torque compared to what you now have, so a modest TC will work very nicely. The question is, and we already know the answer, do you have adequate torque now? No, you don't, else we wouldn't be having this conversation. But choosing those 3.23s, this will increase that low rpm torque 17% as already figured, over 2.76s. And the modest Tc will allow your small engine to spool up to a higher rpm, where the engine is naturally making more power....... because that is how the formula works; namely;
torque times rpm = power. By the formula, if you increase either the torque, or the rpm, an increase in power has to follow. So increasing from 1750(I'm guessing at your current stall, it could be as high as 2150, IDK) to 2800 is a huge deal. Since we are talking about 3.23s that cruise at 65=2610, there is a 200rpm difference that is sortof on the wrong side of locked-up. This means the TC could be slipping all the time while cruising, so the cooler may be required, and is a good idea.
Anytime the TC is not hydraulically locked, that is to say slipping,it is putting horsepower into the oil,heating it up.
Every time you take off from zero mph, the TC will be heating the oil.
Every time a shift is in progress, the oil will get heated.
All this heating has to be controlled.
If you were the kindof guy that just tools around all evening, you would not need cooling beyond what the factory provides.
If this car was a drag car it would definitely need a cooler.
If you are inbetween, then a cooler is cheap insurance.
On a sidenote, I ran an A904 with the A999 gears and a 2800 several winters with no cooling whatsoever, with several different rear gears, and it didn't seem to gibachit about it.

Now, as to your question;
"Will I see more rpm at cruising speed or is the increased stall mostly noticed at high-load low speed."
Simple answer is yes, and no.
With 3.23s, 65=2610 mathematically.
With a 2800TC there is gonna be 190rpm slippage, mathematically, at 65 mph.
but since you don't have a loc-up, that TC could be slipping either way from it's zero slip rpm.
That is to say;
at 65 mph, the rpm could be anywhere from, I'm guessing 150 rpm less that 2610 to the 2800 stall, depending on the load being presented to the TC. On a hard, level,flat, hiway it could be towards the middle, but climbing a hill or bucking a wind it might be towards the hi side, and with a tailwind towards the low side. On a softer surface who knows.
The increased stall makes the biggest difference at zero mph. From idle of say 700 to 2800 is 2100 rpm, and when you nail it from a stop it's like swinging a big hammer; nothing happens until the hammer hits the target, and then all hell breaks loose. After the hit, at WOT and banging thru the gears, you will never know that 2800 is in there.
 
I must have been too tired this morning. A factory performance 318 would have also included compression and better heads so basically would just be smaller 340. Doesn't really apply to my situation now that I'm fully awake! I actually used the
MP P4452757 in a truck 318 several years ago but made the mistake of using stock 360 heads because the ports matched the factory 4 barrel intake I had. It actually pulled well from about 20-25 mph on up but I was probably lucky if the compression ratio was 7.5-1. The truck also had headers and 3.21 gears so the low-end was no worse than stock 2 barrel but definitely no improvement either. I think I remember the cranking compression being about 130.

Anyway, I think you have all helped me come up with a plan. Since I've already got the 600 carb, Performer intake, new timing chain, and all the necessary gaskets purchased, I'll go ahead and get a 248ish cam with lifters and springs so I can do it all at once.
It sounds like I may give up a little on extreme low-end but will definitely extend power-band and have lots more power once moving. I know I will be able to bump timing to at least 12 initial 36 total which should help also. More long-term I'll be looking for a rear axle with 3.21-3.23 gears to replace existing. After all of that, if still not satisfied, it sounds like a stall convertor would really pick things up.

It's too bad us Mopar guys don't have an easy affordable way to run 4.10's with an overdrive tranny for the best of both worlds.
 
slant
are you running coolant through the radiator
you have to have some lube to lube the back of the tranny
give me a shout
I'm back in town
 
I thought I had a decent understanding of cams but the more I look at some of those recommended the more confused I get. The Edelbrock Performer that RRR referenced is 204 at .05 and .42 lift but 270 overall which seems large. The Lunati Voodoo is 208 and 213 at .05 and .454 lift but only 250/256 overall. Yet, when I read a description of both cams they claim to behave similarly. Am I seeing the difference in older slow ramps versus newer fast ramps, and if so, are the newer style cams a lot harder on the valvetrain and seats? Should I just ignore advertised duration and just look at lift and duration at .05? I also looked at the Sealed Power CS1006R and it says 204/204 .42 lift but 278 degrees overall! As near as I can tell, stock 318 cam is 240/248 and .373/.4 lift but can't find numbers at .05. 30 degrees more duration sounds like a lot. What am I missing?
 
Advertised duration very from company to company it’s not the best way to compare cams.

look at cams that say they start off idle or at most like 1200, that work with stock stall and gears with a 318.
 
I’d go with something like comps 255deh works well with manifolds.
 
RustyRatRod said:
Ain't it funny that my recommendation sucks, but every other recommendation is dancing all around mine? lol
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You suggested that cam to me a long time ago. Looks like a dandy for a stock 318. I thought it might idle a bit rough but it doesn't. even in a short stroke Ford motor.
 
RustyRatRod said:
Ain't it funny that my recommendation sucks, but every other recommendation is dancing all around mine? lol
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Actually, while searching the forum, I found one of your posts from a couple years ago where you basically answered my question above about the differences in duration. It looks like the cam you recommended would be a good budget choice that would be easy on the valve-train. I never realized that advertised duration varied so much between manufacturers. It does look like a more modern grind with faster ramps might be slightly more torquey but at the expense of extra noise and shorter valve-train life. I use my car as a daily driver during nice weather, so giving up durability is not something I want to do. Did you use the Perfomer cam specifically or one of the similar knock-offs? My apologies if I have stepped on your toes. Just trying to learn as much as I can.
 
273
.050 is useful for power but .200 is better (or .300)
\
You have to convert "advertised" into .004, .006. 008 etc then you can sorta compare(or use a camdoc)
unfortunately it's the only way to get a grip on dynamic compression and dial in a low compression motor or figure how much static compression you can use, etc

for example using everyone's favorite 50 year old profile
MTC-1 melling version (they are all the same)
.050 open close dir SAE open close dur lobe valve C/L
INT. -5 ATC 29 ABC 204 27 BTC 71 ABC 278 .280 .420 112

EXH. 44 BBC -10 ATC 214 76 BBC 32 ATC 288 .295 .433 112

so we have an
intake intensity of 278-204= 74 intake close 71 ABDC
exhaust intensity 288 -214 =74 Exhaust open 76 BBDC

now that comp and the other similar cams close the intake in the low 50's
and we see that the 204-214 uses .004 and the comp uses ,006 that's not 20 degrees
Trying to make cams that were designed for high compression premium gas motors (like this one and the HP cam) just can't build dynamic compression
as for top end power 204 is not going to do it but if 204 is what you need for your build these cams give up 30-50 thou valve lift
 
1973dust said:
Actually, while searching the forum, I found one of your posts from a couple years ago where you basically answered my question above about the differences in duration. It looks like the cam you recommended would be a good budget choice that would be easy on the valve-train. I never realized that advertised duration varied so much between manufacturers. It does look like a more modern grind with faster ramps might be slightly more torquey but at the expense of extra noise and shorter valve-train life. I use my car as a daily driver during nice weather, so giving up durability is not something I want to do. Did you use the Perfomer cam specifically or one of the similar knock-offs? My apologies if I have stepped on your toes. Just trying to learn as much as I can.
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Usually, when someone asks about a cam for the STREET, I take them at face value and offer a good STREET recommendation. Whatever that recommendation is, usually will not include a fast rate of lift "modern" grind, because if you drive something on the street either every day, or close to it, you don't want something harsh on the valve train. You don't want something that will have valve train noise "no matter what" you do. A lot of times with those fast rates of lift cams, that's what you end up with.

I look at it like this. No matter "what" cam you choose for "whatever" project, you will leave power on the table. You can run yourself ragged trying to pick one that won't but you'll just take the fun out of it. I try to make recommendations based on what I know about camshafts (admittedly more know a lot more than I) and personal experience. I don't get all the formula books out and try to whip up a bunch of numbers to confuse someone already confused before they ever asked their question here. Besides, "what if" you tell me you have a 9.5:1 engine for example and a mistake was made "somewhere" along the way and you really don't? That means all those numbers and calculations about cylinder pressure and this and that are now incorrect.

No, I much rather like to "ballpark" it because there is more "fudge" room so to speak. Now, were you building a race car for bracket points or the like, then that's a whole different ball game. Then we need to get the burrette out and start measuring cc's.

.....and lastly, it's not about using "MY" recommendation. That part is not even part of the picture. I will say this. It's funny that everybody else's recommendations are pretty much spot on with what I said. Use them as a guide. Want more bump? Go up 2-4 degrees in duration and or tighten the lobe centers from 112 to 108 or do both. Just remember, that when you do that, you are trading off bottom end torque for a mid range/top end charge. With a 318, you need to be careful because you can turn it into a dog real quick on the bottom. That's why I tend to err on the small side with the 318.
 
1973
That's what it looks like but not what actually happens
The chevy lobes are actually more radical than the Mopar lobes
you can use the larger lifter diameter at less acceleration and still get more performance
you can look in the comp catalog where they give the intensities for both the opening and closing sides
the XE274HL is not as radical as the XE268

if it really is a concern consider Engle's milder series or MP They wear extremely well as does Jones Motorhome profile other vendors have choices
RRR may have a point about the Voodoo and Howards which push the envelope - as does the comp XE series
cheers
 
RustyRatRod said:
Usually, when someone asks about a cam for the STREET, I take them at face value and offer a good STREET recommendation. Whatever that recommendation is, usually will not include a fast rate of lift "modern" grind, because if you drive something on the street either every day, or close to it, you don't want something harsh on the valve train. You don't want something that will have valve train noise "no matter what" you do. A lot of times with those fast rates of lift cams, that's what you end up with.

I look at it like this. No matter "what" cam you choose for "whatever" project, you will leave power on the table. You can run yourself ragged trying to pick one that won't but you'll just take the fun out of it. I try to make recommendations based on what I know about camshafts (admittedly more know a lot more than I) and personal experience. I don't get all the formula books out and try to whip up a bunch of numbers to confuse someone already confused before they ever asked their question here. Besides, "what if" you tell me you have a 9.5:1 engine for example and a mistake was made "somewhere" along the way and you really don't? That means all those numbers and calculations about cylinder pressure and this and that are now incorrect.

No, I much rather like to "ballpark" it because there is more "fudge" room so to speak. Now, were you building a race car for bracket points or the like, then that's a whole different ball game. Then we need to get the burrette out and start measuring cc's.

.....and lastly, it's not about using "MY" recommendation. That part is not even part of the picture. I will say this. It's funny that everybody else's recommendations are pretty much spot on with what I said. Use them as a guide. Want more bump? Go up 2-4 degrees in duration and or tighten the lobe centers from 112 to 108 or do both. Just remember, that when you do that, you are trading off bottom end torque for a mid range/top end charge. With a 318, you need to be careful because you can turn it into a dog real quick on the bottom. That's why I tend to err on the small side with the 318.
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BRAVO!!! The common sense approach to 318 cam selection.
 
...so once again almost zero recommendations for a "one step above stock" 318 cam


custom grind

.500 lift or more

buy a loose converter

nothing better than the stock .400 lift

etc

I thought we were making progress on the last thread and even had IIRC 2 contenders and a bit of "why this is better than that"

Which I absolutely LOVED.

What happened to that thread anyway?

Should probably be a sticky as much as this question gets asked.
 
Maybe a long shot, but look for an original 273 commando engine and take the
cam,solid lifters,pushrods and rocker assembly. I never saw or ran this in a 318,
I would think it would do you OK. New anything today is hit or miss.
 
66jim said:
Maybe a long shot, but look for an original 273 commando engine and take the
cam,solid lifters,pushrods and rocker assembly. I never saw or ran this in a 318,
I would think it would do you OK. New anything today is hit or miss.
Click to expand...

I think that would probably run pretty good. Maybe a tad big on the duration, but you could advance that little solid and fix all that.
 
...and now we're swapping in an entirely different valvetrain...


There has GOT to be a .42x-.44x hydraulic lift cam that doesn't have 300 degrees of duration that won't kill the low end, but will provide a decent boost in low and midrange power, and without killing MPG.
 
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