Cam & head upgrade 360 mag

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pjc360

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I've got a 300hp crate 360 magnum in my 91 power ram short bed 4x4 truck.
I am running the mopar dual plane m1 intake with a 2 inch 4 hole aluminum carburetor spacer.
A quick fuel super street series 680cfm vaccum secondary carburetor.
A mopar distributer, running 16 degrees initial and 34 total timing. Hedman 1 5/8 long tube Hedders with a dual exhaust with 2 1/4 inch exhaust with an H pipe.
The power is good, specially the torque considering I'm running 3.55 gears with 33 inch tires, I'm swapping gears this spring, I'm going to go with 4.56s or 4.88s, haven't decided which gear to go with, I have the non lock up A-518 transmission with overdrive so I can run a low gear for better street power and still have good highway cruising.
I'm going to swap to a bigger camshaft and I'm considering swapping to the iron ram heads from Hughes engines that come with the bigger 2.02 intake valves and that also comes with the la intake bolt pattern so I have a variety of different manifolds to choose from, even though I haven't had a problem with the dual plane m1, but I've been told by many people that it will struggle to make 400hp which is my goal with the bigger cam and heads, I was thinking I would run a thinner .028 head gasket to bump the compression up a little bit.
I've been told with a .028 head gasket the compression should jump to 9.5:1 and it's at 9.0:1 right now.
The camshaft I am considering running is from Hughes, the cam I am looking at is the ser2226aln-10, intake duration at 50 is 222 and on the exhaust it's 226 and the lift is .549 on the intake side and .555 on the exhaust.
Will this camshaft work well with what I'm doing? I'm trying to create a truck that has a lot
Of take off power and that will keep pulling hard all the way up to around 90-100 mph, I am trying to make it scream from stop light to stop light, not because I'll be racing it on the street, but because I will be using it as a play truck in the mud and and mountains and occasionally drive it around on the streets.
Do you think I should run the bigger 2.02 intake valves if I decide to get the iron ram heads or stay with the stock sized 1.92 valves?
 
Bigger valves are a win win. The engine should have ZERO problems with a 2.02 valve. Between the two heads, you choose which fits best.

The M1 DP is a fine intake and capable. While the RPM style intake would be better, I don't think it is mandatory to use for 400HP at all.

2 things stick out on this build;

1; Talk to Hughesengines for a camshaft for the goal.

2; You current exhaust size is a fork for the goal. Graduate on up to 2-1/2 inch piping.

Your goal depends on a good balance of the above two parts.
 
Based on the little knowledge I do have on camshafts and based on the conversations ive had with people who do know quite a bit more then I do about camshafts that cam from Hughes should work out pretty well for my goal, I was also going to have some
Mild port work done to the heads before I put them on.
 
I've heard that dual 2 1/4 inch exhaust is good till 400-450hp and that it's not really a restriction untill your over 450 horse, but then again exhaust is a very complicated equation and topic.
 
I used to have a website that had the whole exhaust thing figured out. As engines are basically air pumps, they pump out a certain CFM of air at certain horsepower. This website showed what pipes flowed what CFM. And told you what aprox horsepower matched with what pipe. If I recall, 2-1/4 was good for just under 400. But the website seems to be down right now. This is the chart they came up with:

http://www.ls1gto.com/forums/attachment.php?attachmentid=149219&stc=1&d=1332948156

It's all backed by some math that seemed to check out to me. So that's what I run with.
 
Does that Hughes camshaft seem too big for a 4x4 truck? I figured it would be ok with the 4.56 gears and a duel plane intake, but I don't know a lot about camshafts. That's why I'm asking you guys.
 
Getting Magnum heads with the LA intake bolt pattern does open up the number of intake available. What you need to keep in mind is the port opening for LA and Magnum are different and will require port matching.

You need to build for torque. 400+ft-LBS is gonna mean more then 400HP. I think the cam you are considering is appropriate. You will need to verify retainer to guide clearance.

A good converter makes a world of difference and converting your 518 to non lockup opens up a world of 727 converters you can use. I re-used my 9.5" Edge racing converter from my 904 in my A500 I had converted to non-lockup. The deeper first gear over the 904 was a plus.
 
Give Brian here (IMM Engines/"Ou812) here,a P.M... You might be surprised.
 
-Do you realize that swapping to 4.56s will make the engine feel 4.56/3.55=1.28 or 28% bigger. Throughout the rev range.And the shifts will come much sooner and closer together? 28% is huge! It will feel like you put a big block in there, compared to the former performance.
-It is my opinion that before you spend a ton of cash, do the gear swap first.
-Right now; with the 33s,the 3.55s and a 5000rpm shift speed, your road speeds at the shift are 56,95,and 138mph
-With a swap to 4.56s, the road speeds at 5000 will be 44,74, and 108. That would be 12mph sooner,21 mph sooner, and 30mph sooner.
-Lots of good suggestions from previous posters.

FWIW; I've got dual 3inch exhaust on my little 367 cuber, and have never been sorry, even when I ran a low compression teener winter motor. They are a bit loud tho at WOT.
 
I know a lot of my power is lurking in them gears, I am doing the gear swap before I change the cam and heads, because I know I might be more then satisfied with the way it performs.
I just know myself and once I do the gears I'll want more out of it.
How much more is yet to be determined, I've considered a stroker kit, but I don't want to spend that much money, specially when I can get quite a bit more power from a bigger camshaft and better flowing heads.
And a new camshaft and the iron ram Eq heads isn't really that expensive.
 
I have built Magnum powered 4x4's for last 20 years so very familiar with heavy vehicles, deep gears and large tires.

What rpm do you shift at?
What is stall of converter?
What is total weight of truck, 5000+#?
4.56-4.88 is pretty deep gear for 33's, do you plan on going bigger than 33?
Playing in mud requires lots of tire speed and quick reving engine.
Quick launches in big vehicles requires lots of torque, low end torque with low stall converter.
IMO cam is a bit long in duration for such heavy vehicle without converter and not sure you would benefit from the 2.02 upgrade unless you plan on more than 5000 rpm. Again just my $.02
Very important to have a very well matched combo. What some might not realize is this truck probably weights 1 1/2 times of an a body which will make a huge difference in cam, converter and intake. I would probably step up to a 2 1/2" dual exhaust but only if you expect to run above 4500 rpm for extended periods.
Feel free to call the shop if you have any questions, 541-955-0363 9-6 pacific time. Evan
 
Truck weighs about 5000 pounds, give or take a couple hundred pounds.
I'm guessing the converter has the stock stall, whatever that may be.
I did have the transmission re-built and it got a new converter, idk what the stall is on it but I do know it's a non lock up converter and it does have the transgo Jr shift kit in it.
Right now I normally shift at 4500-4800 rpm whenever I'm running it against someone in the mud or on the street.
I realize that cam does have quite a bit of duration, but if I do decide to get the camshaft I'm also going to get the new heads and I will run a thinner head gasket, a .028 thickness head gasket which will bring the compression up from 9.0:1 to 9.5:1.
What camshaft would you recommend for this truck?
 
For a truck I'd consider a 408 (or larger). Low speed toque is a must for heavy trucks. I went from a 351m to a 460 in my F-150 and the low speed torque is awesome. I no longer have rev it to 4K to pull a grade or even just to get the damn thing to scatter it's own poop. All that a cam will do is shift your RPM band higher, and you'll need a converter and gears.
 
I can't afford a stroker right now. But maybe if I just paid to have the gears done and then left the engine alone and saved up I could have enough for a stroker in about a year to a year and a half.
I'm already getting gears, that's a must for me right now, I wouldn't mind buying a converter if I needed one with a higher stall.
I don't want to make this a high rpm screamer, but I would like to get in the neighborhood of 400 hp with it.
I know the torque is very good on this engine and is most likely around 400 ft lbs right now, it's advertised at 385 ft lbs.
 
This is what I did to my 2003 360 300 HP Magnum Crate:

360 Magnum roller, 9.3:1, OEM magnum heads milled .010, .028 head gasket, stock valves, MP crate motor springs, ported by me at home.
Knockoff airgap, demon 650 DP, Lunati roller steel core custom grind 234/236 .495/.475 lift. 108 LSA/106 ICL
999 low gear set, TF2 shift kit Lockup circuit disabled, Turbo Action 10" 3200-3400, 3.91 SG, 27in MT drag radial, Mancini SS springs, 8.75 axle moved back .75", battery in trunk.

Wallace Racing HP calc for 11.946 ET 3360 lb car
HP computed from your vehicle ET is 350.59 rear wheel HP and 389.55 flywheel HP.
HP computed from your vehicle MPH is 337.14 rear wheel HP and 374.60 flywheel HP.
Motor has over 400 torque and pulls the full 1/4, nose drops only when you lift.
I'm still tweaking to find more top end power. I suspect more gear and converter would do it, but I drive 50 miles to run the car.

OEM Magnum heads are very good and I assume yours are low mileage. They respond well to blow cleanup and port match. You need to be careful with piston to valve clearance with the OEM pistons, there are no valve reliefs. My .010 mill of heads, swap to thinner head gasket, 234@050 dur, and .495 intake lift resulted in .050 P to V clearance. My exhaust was .100 so no problem there.

You don't need to drop a lot of $$$ in your motor. I'm using the same lifters, pushrods, rocker, and valve springs that came with the crate motor. IMO a good Cam and port of what you have will work. Call Justin at Lunati Cams with your combo. The guy is good and won't BS you.
 
mderoy340 said:
This is what I did to my 2003 360 300 HP Magnum Crate:

360 Magnum roller, 9.3:1, OEM magnum heads milled .010, .028 head gasket, stock valves, MP crate motor springs, ported by me at home.
Knockoff airgap, demon 650 DP, Lunati roller steel core custom grind 234/236 .495/.475 lift. 108 LSA/106 ICL
999 low gear set, TF2 shift kit Lockup circuit disabled, Turbo Action 10" 3200-3400, 3.91 SG, 27in MT drag radial, Mancini SS springs, 8.75 axle moved back .75", battery in trunk.

Wallace Racing HP calc for 11.946 ET 3360 lb car
HP computed from your vehicle ET is 350.59 rear wheel HP and 389.55 flywheel HP.
HP computed from your vehicle MPH is 337.14 rear wheel HP and 374.60 flywheel HP.
Motor has over 400 torque and pulls the full 1/4, nose drops only when you lift.
I'm still tweaking to find more top end power. I suspect more gear and converter would do it, but I drive 50 miles to run the car.

OEM Magnum heads are very good and I assume yours are low mileage. They respond well to blow cleanup and port match. You need to be careful with piston to valve clearance with the OEM pistons, there are no valve reliefs. My .010 mill of heads, swap to thinner head gasket, 234@050 dur, and .495 intake lift resulted in .050 P to V clearance. My exhaust was .100 so no problem there.

You don't need to drop a lot of $$$ in your motor. I'm using the same lifters, pushrods, rocker, and valve springs that came with the crate motor. IMO a good Cam and port of what you have will work. Call Justin at Lunati Cams with your combo. The guy is good and won't BS you.
Click to expand...

Milling the heads .010 and running a .028 head gasket got you to 9.3:1 compression?
I was told running the .028 head gaskets alone would increase the compression to 9.5:1.
Like I have said many times I don't know that much about camshafts at all, and I don't want to put something in it that's so big it hurts the bottom end, I like having the throw you back in the seat torque right off the line, with the 4.56 gears I know that's going to be putting a lot more of my torque to the ground.
I basically just want to pick a cam that's going to have good torque all the way through the rpm
Range.
 
pjc360 said:
Milling the heads .010 and running a .028 head gasket got you to 9.3:1 compression?
I was told running the .028 head gaskets alone would increase the compression to 9.5:1.
Like I have said many times I don't know that much about camshafts at all, and I don't want to put something in it that's so big it hurts the bottom end, I like having the throw you back in the seat torque right off the line, with the 4.56 gears I know that's going to be putting a lot more of my torque to the ground.
I basically just want to pick a cam that's going to have good torque all the way through the rpm
Range.
Click to expand...

Milling the heads .010 and running a .028 head gasket got you to 9.3:1 compression?
Yes. I measured everything before and after. The .010 cut was to help CR a little, but more to make sure the head was flat for a good seal with the thinner gasket.

I was told running the .028 head gaskets alone would increase the compression to 9.5:1.
That's a ball park figure. Deck height, head CC, etc. is +- from the factory. You will never feel the difference of a .2 change of CR IMO. After 10K miles a little carbon build up will raise the CR that much.
 
pjc360 said:
Truck weighs about 5000 pounds, give or take a couple hundred pounds.
I'm guessing the converter has the stock stall, whatever that may be.
I did have the transmission re-built and it got a new converter, idk what the stall is on it but I do know it's a non lock up converter and it does have the transgo Jr shift kit in it.
Right now I normally shift at 4500-4800 rpm whenever I'm running it against someone in the mud or on the street.
I realize that cam does have quite a bit of duration, but if I do decide to get the camshaft I'm also going to get the new heads and I will run a thinner head gasket, a .028 thickness head gasket which will bring the compression up from 9.0:1 to 9.5:1.
What camshaft would you recommend for this truck?
Click to expand...

I have a cam I use in our stage II magnum build running FI but will be a great carbcam for your weight, shift points and factory converter. 213 @.050 525" lift 112 deg LSA. Works great with compression of 9-1, lots of vacuum for quick throttle response, makes torque right off the bottom.

If it were my truck, or at least my customers truck that said "this is what I do, build it for me" I would recommend OOTB EQ heads(brace for *^#% storm..), Stage II spring package , Stage II cam and either our stainless roller tip/stud/guide and pushrod package or step up $100 more and go same package with stainless full rollers, NGK Plugs gapped at .050 w good coil, good DP intake and nothing more than a 750 cfm.
At your shift point and converter stall I would save porting $$ or larger valves for your gear swap. I know it sounds conservative but your truck weights 1 1/2 times an a body and the more important factor, your tire/wheel combo weights 2-3 times of car tire/rim combo and drive train requires much more torque to spin 2 axles and a transfer case. These are torque vampires, compared to 904, 8 1/4 w 245r60 15 in a car.

Now before people start throwing rocks, let me explain. It has been proven by flow bench and dyno that port work on EQ heads makes huge power gains BUT these gains all seem to be in the part of the power band that is very close to your shift point and higher. This comes at a sacrifice of lower end power. The torque required to start spinning 4 33" tires and transfer case is huge and needs to happen right away, not in the middle to upper power band. You need it right away to get everything moving, just like in sand or a sled pulling truck. If you had a HS converter, bigger cam and more compression you could get what you need but up higher in torque curve ie start launching at 3K shifting at 6K . Your stock converter should stall at close to 2K with enough torque which should be a good launch rpm if shifting at 5000-5500 rpm. You will probably find yourself shifting closer to 5500-5700 with this new combo as it should pull hard past 5K.

I have built many many pulling truck and tough truck engines, some were high revving huge cam and some were a very sensible but beefy build like this. With your combo I feel the low end torque beast would suit you better. It also leaves you very open to future upgrades without wasting any hard earned cash. With a $199 roller you could always sell to a buddy if you decide to move up in converter, displacement or compression later. Here is the best part, the cost.

$1139 shipped EQ heads with Stage II spring upgrade good to .575" cam
$179 Roller cam- reground. $199 but on sale for $179
$89 Pro Gear Timing set 3 key. (yours might be roller, might not)
$299 Stainless Roller Tip Rockers, CC studs/guide plates, CroMo .080" hardened pushrod kit
Add $100 if you want Stainless full rollers.

You can save even more by reusing your factory rocker arms and only replacing the pushrods which are $99.

$1700 if you need timing set. If it has roller set in good shape, reuse it and save $89 .
$1418 if you reuse MP rockers and timing set.

I would guess you should end up around 375 HP and 425 ft lbs TQ. We have yet to dyno this combo. We can also give Racer Brown a call to "fine tune" your grind on the cam for carb use.

PM or call the shop if you want more info, 541-955-0363 9-6 pacific time Evan
 
magnummopar said:
I have a cam I use in our stage II magnum build running FI but will be a great carbcam for your weight, shift points and factory converter. 213 @.050 525" lift 112 deg LSA. Works great with compression of 9-1, lots of vacuum for quick throttle response, makes torque right off the bottom.

If it were my truck, or at least my customers truck that said "this is what I do, build it for me" I would recommend OOTB EQ heads(brace for *^#% storm..), Stage II spring package , Stage II cam and either our stainless roller tip/stud/guide and pushrod package or step up $100 more and go same package with stainless full rollers, NGK Plugs gapped at .050 w good coil, good DP intake and nothing more than a 750 cfm.
At your shift point and converter stall I would save porting $$ or larger valves for your gear swap. I know it sounds conservative but your truck weights 1 1/2 times an a body and the more important factor, your tire/wheel combo weights 2-3 times of car tire/rim combo and drive train requires much more torque to spin 2 axles and a transfer case. These are torque vampires, compared to 904, 8 1/4 w 245r60 15 in a car.

Now before people start throwing rocks, let me explain. It has been proven by flow bench and dyno that port work on EQ heads makes huge power gains BUT these gains all seem to be in the part of the power band that is very close to your shift point and higher. This comes at a sacrifice of lower end power. The torque required to start spinning 4 33" tires and transfer case is huge and needs to happen right away, not in the middle to upper power band. You need it right away to get everything moving, just like in sand or a sled pulling truck. If you had a HS converter, bigger cam and more compression you could get what you need but up higher in torque curve ie start launching at 3K shifting at 6K . Your stock converter should stall at close to 2K with enough torque which should be a good launch rpm if shifting at 5000-5500 rpm. You will probably find yourself shifting closer to 5500-5700 with this new combo as it should pull hard past 5K.

I have built many many pulling truck and tough truck engines, some were high revving huge cam and some were a very sensible but beefy build like this. With your combo I feel the low end torque beast would suit you better. It also leaves you very open to future upgrades without wasting any hard earned cash. With a $199 roller you could always sell to a buddy if you decide to move up in converter, displacement or compression later. Here is the best part, the cost.

$1139 shipped EQ heads with Stage II spring upgrade good to .575" cam
$179 Roller cam- reground. $199 but on sale for $179
$89 Pro Gear Timing set 3 key. (yours might be roller, might not)
$299 Stainless Roller Tip Rockers, CC studs/guide plates, CroMo .080" hardened pushrod kit
Add $100 if you want Stainless full rollers.

You can save even more by reusing your factory rocker arms and only replacing the pushrods which are $99.

$1700 if you need timing set. If it has roller set in good shape, reuse it and save $89 .
$1418 if you reuse MP rockers and timing set.

I would guess you should end up around 375 HP and 425 ft lbs TQ. We have yet to dyno this combo. We can also give Racer Brown a call to "fine tune" your grind on the cam for carb use.

PM or call the shop if you want more info, 541-955-0363 9-6 pacific time Evan
Click to expand...

I believe the torque should be darn close to 425 ft lbs and I base that thought on an article
I read where they took a 300hp crate 360 magnum (same engine I have) they put a set of long tube Hedders on it, put an msd distributer and ignition on it and a 750cfm speed demon carburetor with the mopar dual plane m1 intake manifold and it made 319hp and 424 ft lbs of torque.
I'm running a mopar distributer that was set up by don at fbo systems, running 16 degrees initial timing and 34 degrees total timing, I'm running the mopar dual plane m1 intake with a 2 inch 4 hole aluminum carburetor spacer and a quick fuel super street series 680cfm vaccum secondary carburetor. I'm running Long tube Hedman Hedders 1 5/8 tube diameter and a crane cams hi-6 cd ignition.
I haven't had my engine dynoed, but based on what the 300hp 360 magnum made for the guys that did the article I would bet mine has to be very similar. I'm running a way better carburetor then a speed demon and the same Hedders and a better ignition.
I am already running ngk v-power plugs gapped at .50, with Taylor thundervolt 8.2mm wires.
I believe you when you say a milder cam then the Hughes ser2226 would probly be a better ide to maintain good torque down low, I just figured the lower 4.56 gears would help make up for a bigger camshaft.
I was told I could re-use the mopar lifters and rockers when I do a camshaft upgrade.
You would recommend staying with the stock sized intake valves over the bigger 2.02 valves?
And you would recommend some porting on the Eq heads?
The items seem priced well, who re-grinds your cams for you?
I've heard great things about the Hughes cams and that what has got me looking at them for a new camshaft.
Are new push rods required with a new cam and new heads?
And I think my engine should have a good timing chain on it, the engine barely has 20 thousand miles on it. My dad bought it brand new in 2003.
 
"I believe you when you say a milder cam then the Hughes ser2226 would probly be a better ide to maintain good torque down low, I just figured the lower 4.56 gears would help make up for a bigger camshaft.
I was told I could re-use the mopar lifters and rockers when I do a camshaft upgrade.
You would recommend staying with the stock sized intake valves over the bigger 2.02 valves?
And you would recommend some porting on the Eq heads?
The items seem priced well, who re-grinds your cams for you?
I've heard great things about the Hughes cams and that what has got me looking at them for a new camshaft.
Are new push rods required with a new cam and new heads? "

Low gears will make up for cam, assuming the converter is loose enough for the engine to get into torque band before it hits. Otherwise it will just bog the engine instead.

Based on how the EQ heads respond to larger valves, you will loose airflow around .200"-.300" which will mean less torque down low and more up high where you dont need it. Same goes for porting the heads, They work really well OOTB and porting can cause some low pressure flow.
We are currently beating summit and jeg on the parts...our cams are built by Racer Brown of Mopar fame.
Hughes makes good cams, we just have a slightly different opinion backed by Racer Brown which probably doesnt make a big HP difference in the level of build that we are talking about. If you get a new cam, then pushrods will work, regrind requires longer ones. Rockers will work up to .525"-.530" lift.

You should see substantial gains going from .420" lift to .525" and under 200 duration to 212. Stock EQ should flow about 15% better than what you have which would equate to a very large port job on the stockers
 
rumblefish360 said:
Bigger valves are a win win. The engine should have ZERO problems with a 2.02 valve. Between the two heads, you choose which fits best.

The M1 DP is a fine intake and capable. While the RPM style intake would be better, I don't think it is mandatory to use for 400HP at all.

2 things stick out on this build;

1; Talk to Hughesengines for a camshaft for the goal.

2; You current exhaust size is a fork for the goal. Graduate on up to 2-1/2 inch piping.

Your goal depends on a good balance of the above two parts.
Click to expand...

How much horsepower can the mopar dual plane m1 support before it starts becoming a restriction?
 
They have made 400+ on dyno. Edelbrock AG might get you another 5-7 but probably over 5500 so I would spend your $$$ on something else that would make a larger difference.
 
I didn't plan on swapping to the air-gap, I was running the edelbrock air-gap and I didn't like the way it performed in cold weather, i live in Montana where it gets real cold and the engine felt sluggish with the air gap when it was real cold out, and the fuel mileage was suffering.
When I swapped back to the mopar dual plane m1 I noticed it ran much better in cold weather and I also noticed slightly better fuel mileage.
A lot of ppl trash the m1 dual plane intake, saying its just a stock intake and they don't perform that well. I was just wondering why ppl don't really like them?
If they can support 400hp that seems like a decent manifold to me, and doesn't the m1 dual plane have larger ports and larger runners over the factory cast iron 4bbl intakes?
I thought I read that somewhere, and I like the position of the thermostat housing and the by pass hose better on this dual plane m1 over the air-gap, it just looks better and the hoses fit better in my opinion. And I like where the vaccum port is for the power brakes on this dual plane m1 over it being on the passenger side on the air-gap.
 
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