Mopar Muscle Magazine 360

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This would be my min.
COMP Cams Xtreme Energy Retrofit Camshafts 20-811-9
Though I’d probably run into he next one up, to be honest;
https://www.summitracing.com/parts/cca-20-813-9/overview/
But would rather run this solid roller with 1.6 rockers on a fully ported aluminum head @ 11-1 compression ratio.
https://www.summitracing.com/parts/cca-20-741-9/overview/

Though this one is next in line ... ready to start the build... or so I believe ... LOL!!
Voodoo Solid Roller Cam - Chrysler 273-360 279/285 - Lunati Power
 
IF and I really stress that word “IF”, I could get one with a 59* cam and a single plane (a tunnel ram would be OK as well...), I’d have a ball!
 
The IMM dyno is a good unit for actual HP and not inflated like some are. Cars run the numbers that you'd expect from the dyno results.

Their is NOTHING wrong with those thmper hyd roller cams. They work well when sourced with complimentary components. A different cam could be used with a wider LSA, depends on what you are looking for.
 
As long as the race block has the 273/318/340 mains, yes.
 
The IMM dyno is a good unit for actual HP and not inflated like some are. Cars run the numbers that you'd expect from the dyno results.

Their is NOTHING wrong with those thmper hyd roller cams. They work well when sourced with complimentary components. A different cam could be used with a wider LSA, depends on what you are looking for.
I'm just looking for a fun street car and fun at tge strip when my buddies go, I could actually tag along. But drive mine home lol. The one runs 10.70 in an Opel with a 350 and one has a 32 Chevy pickup and runs 11.40s. I'd like decent 12s and still drive home. Would the 107 be that much better than a 110?
 
I got my 360 magnum for next to nothing from a guy who had a junk van just sitting in his driveway. $120 was a fair deal, he pulled it. I was just wanting to have a cheap build up and later down perhaps stroke it. Thanks for your advice. Too bad there aren't any Mopar motor gurus I know of in Columbus, Ohio :(
Seriously? There is not a good Mopar shop in the home of the Mopar Nats??
 
Run this one with a 1.6 rocker;

Summit Racing Part Number:CCA-20-813-9


UPC:036584117889

Cam Style:Hydraulic roller tappet

Basic Operating RPM Range:2,500-6,200

Intake Duration at 050 inch Lift:236

Exhaust Duration at 050 inch Lift:242

Duration at 050 inch Lift:236 int./242 exh.

Advertised Intake Duration:286

Advertised Exhaust Duration:294

Advertised Duration:286 int./294 exh.

Intake Valve Lift with Factory Rocker Arm Ratio:0.544 in.

Exhaust Valve Lift with Factory Rocker Arm Ratio:0.541 in.

Valve Lift with Factory Rocker Arm Ratio:0.544 int./0.541 exh.

Lobe Separation (degrees):110
 
Package eight:
360 rebuilt with 9.5 to 1 cast pistons, original crank, rods and windage tray. 202 heads with competition valve job and ported to flow 260 cfm. Edelbrock RPM intake, Holley 750 rejetted, Large tube headers and Mopar Performance P4120231 cam with .484" lift, 284 duration, 108 lsa, installed at 106 intake centerline.
460 h.p. @6000 rpm
486 lbs. of torque @ 4,250 rpm. Just an LA motor but proven cheap build. That's a streetable cam.
 
There all gonna give you similar performance. The reason I picked comp xr274hr is cause your running a bit heavier of a car. Youll would have to watch the compression on that one.

Rumbles cam is basically the 110 version of the thumper. But still will have a very healthy Idle.

The thumper will sound lile a top fuel car :)

You really can't go wrong. Especially with 4.10 out back.
 
There all gonna give you similar performance. The reason I picked comp xr274hr is cause your running a bit heavier of a car. Youll would have to watch the compression on that one.

Rumbles cam is basically the 110 version of the thumper. But still will have a very healthy Idle.

The thumper will sound lile a top fuel car :)

You really can't go wrong. Especially with 4.10 out back.
Thanks for your help! The Coronets shipping weight was 3285 with a slant so about 3400lbs with a 360 is my guess. Currently has its numbers 318 still chugging along. What stall would be good with the thumpr or its 110 LSA cousin in your opinion?

I love this forum and how everyone helps out. I'm glad such a resource is easily accessible.
 
That cam is making 1.27 lbs ft per cid thats pretty good. Could alway use about a 235 cam with .550 lift on 110 would be similar.

I compared comps smallest roller thumper with a roller 265 on 114. Half the opening and close points were the similar. I guess thats why they kind of give you both worlds.

Im sure the 380hp create engines cam is mopars version of a thumper cam. Works pretty good its a little soft under 2000 rpm but the only reason I notice cause my car is geared wrong 2.96 instead of 3.55 plus gears. Single plane intake dont help either.
This would be my min.
COMP Cams Xtreme Energy Retrofit Camshafts 20-811-9
Though I’d probably run into he next one up, to be honest;
COMP Cams Xtreme Energy Retrofit Camshafts 20-813-9
But would rather run this solid roller with 1.6 rockers on a fully ported aluminum head @ 11-1 compression ratio.
COMP Cams Xtreme Energy Camshafts 20-741-9

Though this one is next in line ... ready to start the build... or so I believe ... LOL!!
Voodoo Solid Roller Cam - Chrysler 273-360 279/285 - Lunati Power
Rob that Comp 20-811-9 sure looks like LxGuys cam.
And for 273 ,He wanted my retrofit hydraulic roller cam specs . Hopefully, it's readable...

20171229_012910.jpg
 
ET is about the Chassis and Converter. MPH is more a measure of HP. If you want the car to charge HARD, spend money on a GOOD CONVERTER!. It's the single most important piece in an automatic car, IMO. Get something that flashes to a high RPM yet is still somewhat tight on cruise. A good converter guy cna put that together. Flash to 4K is a good thing for getting the car moving.

You'd be surprised how little HP it really takes to get a good working car down a strip. Where in the 12's? 12.9's are a lot easier than 12.0's. :)

110 LSA would have better idle manners, generally a broader powerband.

At 3600# you are going to need anywhere from 350 to 450hp is my guess for 12's range.
 
Thanks for your help! The Coronets shipping weight was 3285 with a slant so about 3400lbs with a 360 is my guess. Currently has its numbers 318 still chugging along. What stall would be good with the thumpr or its 110 LSA cousin in your opinion?

I love this forum and how everyone helps out. I'm glad such a resource is easily accessible.


Its hard to pick the exact cam for ya cause everyone is different. They all have sight compromises. I really come down to person preference. But if you don't venture to far spec wise the performance should be in the ballpark. Its not like theres gonna be 50 hp difference between the thumper and xr285hr or even abodybombers cam. But that 1.27 lbs-ft per cid is pretty impressive from the thumper cam if its a pretty flat curve that will make a good under the hp curve which is more important than peak.
 
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That magazine engine looks pretty good to me;
Except maybe the power-peak at 6000rpm. That kindof demands a 6800/7000rpm 1-2 shift, and about a 6600 rpm 2-3 shift; so your oiling system is gonna have to be tip-top.
I have a similar engine, with a 10.97 starter gear,and a manual trans. It goes like the dickens, even in my 3650 Barracuda. Plenty of of low-rpm power; mine is a dump-it-and-go deal. I seldom need to give it much rpm to launch, and even tho the power peaks at about 5300, the beast pulls forever, and I usually shift it at 7000, when hard-charging. With an automatic, the 1-2 shift would probably be around 6300, maybe a bit higher.
IMO, for a streeter,for your stated useage, I could see one or maybe two sizes smaller cam being an advantage.But only you can make that decision, based on percentage of street-driving versus track time, versus cost of fuel.

Just to relate; I had a 223/110 cam for 4 years and it was a real nice combo. I ran it with a 9.44 starter gear, which was plenty. It would have easily pulled less.That cam peaked around 5000, and I still shifted it at 7000,lol. And it made fabulous fuel mileage,running at 65=1600.........So, what I'm saying is; I really liked that 223 cam.
The current 230 cam, gave up some low-rpm torque, and gained some upper rpm power. The midrange is about the same. But it cannot make decent fuel mileage anymore, at 65=2240. I've been hoping this 230 cam would die since 2004, so I could have an excuse to downsize...... but it just keeps on going, and going, and g........That's real-world experience.
Your results may vary.
For a few bucks more, you can get aluminum heads, and pump the Dcr up to about 9.0 and still run pump gas. The added compression is worth about a cam-size on top, and a ton of midrange and bottom-end. That goes well with a smaller cam,and/or a heavy car. I am running that hi-lift-230 cam on 87E10; same as when I ran the 223.

Nowadays, it's easy to build SBMs with waaay more power than the street chassis can harness. So if you want a tire-frier, that magazine 360 will do it easily. But a little less cam, is IMO still more than the street-chassis street-tires can handle, especially with a 4.10 in the back. And that's my opinion, based on my experience.
 
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That magazine engine looks pretty good to me;
Except maybe the power-peak at 6000rpm. That kindof demands a 6800/7000rpm 1-2 shift, and about a 6600 rpm 2-3 shift; so your oiling system is gonna have to be tip-top.
I have a similar engine, with a 10.97 starter gear,and a manual trans. It goes like the dickens, even in my 3650 Barracuda. Plenty of of low-rpm power; mine is a dump-it-and-go deal. I seldom need to give it much rpm to launch, and even tho the power peaks at about 5300, the beast pulls forever, and I usually shift it at 7000, when hard-charging. With an automatic, the 1-2 shift would probably be around 6300, maybe a bit higher.
IMO, for a streeter,for your stated useage, I could see one or maybe two sizes smaller cam being an advantage.But only you can make that decision, based on percentage of street-driving versus track time, versus cost of fuel.

Just to relate; I had a 223/110 cam for 4 years and it was a real nice combo. I ran it with a 9.44 starter gear, which was plenty. It would have easily pulled less.That cam peaked around 5000, and I still shifted it at 7000,lol. And it made fabulous fuel mileage,running at 65=1600.........So, what I'm saying is; I really liked that 223 cam.
The current 230 cam, gave up some low-rpm torque, and gained some upper rpm power. The midrange is about the same. But it cannot make decent fuel mileage anymore, at 65=2240. I've been hoping this 230 cam would die since 2004, so I could have an excuse to downsize...... but it just keeps on going, and going, and g........That's real-world experience.
Your results may vary.
For a few bucks more, you can get aluminum heads, and pump the Dcr up to about 9.0 and still run pump gas. The added compression is worth about a cam-size on top, and a ton of midrange and bottom-end. That goes well with a smaller cam,and/or a heavy car. I am running that hi-lift-230 cam on 87E10; same as when I ran the 223.

Nowadays, it's easy to build SBMs with waaay more power than the street chassis can harness. So if you want a tire-frier, that magazine 360 will do it easily. But a little less cam, is IMO still more than the street-chassis street-tires can handle, especially with a 4.10 in the back. And that's my opinion, based on my experience.
Thank you for the detailed experience! I'll probably stick with the 455hp blueprint and maybe downsize the cam. I kinda want an excuse to go to National Trails Raceway more :) But I'm partial to my stock tires lol. I plan on installing the stiffening kit from US cartool. But I want a stock appearance with lotsa grunt. I'm putting my LA318 front dress onto the magnum. If I can keep a stocker appearance and have a mean set up I'd be excessively happy. Gas mileage isn't my biggest concern, my truck with its 2.56s and inline 250 go forever at 70mph. Though I got a 10 bolt Chevy rear with 3.73s from a WS6 for free and my truck would be awesome with those and the dual strombergs. So I guess I'm doomed for bad gas mileage haha
 
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If you stick with iron heads and downsize the cam, you will have to pay attention to the cylinder pressure, that it does not get too high for the available octane gas.

At the listed 10.4Scr, that engine is seriously pushing the limits of pump gas with the cam they used. If you go to a smaller cam, you will probably have to increase the TOTAL chamber volume, while keeping the Q in the acceptable range.
 
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Looking at the dyno results when the engine had the 650 CFM carburetor on, it's stopped gaining horsepower at 5800 RPM. then when it had the 750 CFM carburetor at 6000, where they shut off the test, it was still making power. They did not take it to its peak.
That motor is designed for more RPM than 6000 with that combination.
Probably would need some oiling system modifications though if they were going to run at higher rpm for very long.
 
Looking at the dyno results when the engine had the 650 CFM carburetor on, it's stopped gaining horsepower at 5800 RPM. then when it had the 750 CFM carburetor at 6000, where they shut off the test, it was still making power. They did not take it to its peak.
That motor is designed for more RPM than 6000 with that combination.
Probably would need some oiling system modifications though if they were going to run at higher rpm for very long.
I would probably never take it past 6 grand anyway, unless the occasional strip time. I'm looking for a really fun street car, with occasional strip time. I'll probably do a few oiling mods anyway just to make it live as long as it can.
 
If you stick with iron heads and downsize the cam, you will have to pay attention to the cylinder pressure, that it does not get too high for the available octane gas.

At the listed 10.4Scr, that engine is seriously pushing the limits of pump gas with the cam they used. If you go to a smaller cam, you will probably have to increase the TOTAL chamber volume, while keeping the Q in the acceptable range.
What would a recommendation of cam choice be for you then? Or should I just run a slightly thicker head gasket to lower the static CR a bit to be safe
 
What would a recommendation of cam choice be for you then? Or should I just run a slightly thicker head gasket to lower the static CR a bit to be safe


Since I like to rev the crap out of my engines. I would do the oiling system modifications and probably rev that thing to 7500 on more than one occasion. LOL
 
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