Magnum 360 build. (HP/tq?)
- Thread starter ParDaddy
- Start date
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Sounds like we would then.It be up to you then. I know where I stand on this glorious day.
A curmudgeon is a grumpy old fart. Curmudginess means it's showing.
Probably why, we each feel the other operating in bad faith.
psi_duster
Member
Kinda off topic but what porting do they do to the heads? Interested to see since the original engine quest heads aren't available anymore.
Good question. That’s a lot of head flow to start with never mind with any current Magnum iron head today.
ParDaddy
Look Momma, I'm going fast
It's all CNC work developed, in part at latest, by Chris at Performance Injection Equipment out of Delaware. Int. valves are 2.05 and they claim the head flows 290cfm. They have a level 1 head, but for the extra $400 these seemed worth it.
When you look them up, make to go to the SHOP page, hard to find everything through a phone also..
psi_duster
Member
Thanks for that. Found the pictures in the shop page.
I know this is a magnum head but is it a stock ported head or ported aftermarket head.
Dale Davies
Well-Known Member
Valve lift and intake valve diameter gives exactly squat to enable an intelligent answer. What is the head make and flow numbers. What make is the cam and what are the specs, LSA, 0.050 duration and seat to seat duration?
David Vizard's LSA formula tells that cylinder displacement with that intake valve should start with an LSA of 104°. Of course for a serious race engine, that would be the starting point for testing with a few cams.
What is your valve to piston clearance as tested with modeling clay? Did not do that? No worries. Closest approach is about 15° to 10° BTDC and ATDC. Set the engine at the #1 15° BTDC and put a dial indicator on the #1 exhaust retainer. Rotate the rocker to open the valve carefully until the valve contacts the piston. Try 10° BTDC. Then rotate to 10° ATDC to measure the intake clearance. Then rotate to 15° ATDC. This should tell your minimum clearances and indictate if and by how much you can increase valve lift. IMHO this is a big limiting factor for your engine which is fairly easily remedied if you have adequate valve to piston clearance. Higher ratio rockers will open up the flow. The cam is expensive and requires some teardown to replace. If you start with 1.5:1 rockers, going to 1.6:1 rockers will get your lift up to 0.512". Spring coil bind and seat/open pressure may require a spring change. Also retainer to seal clearance would need to be checked. 0.512" gets you into more modern build spec and will let the heads perform. Stepping up on the intake rockers to 1.65:1 ratio with 1.6:1 on the exhaust would likely give more performance. Intake lift would then be 0.528". This is almost 0.050" more intake lift, probably without having to remove the heads. The engine will become snappier and develop more torque. This can also be done after installing and driving the engine, just easier on the stand.
David Vizard's LSA formula tells that cylinder displacement with that intake valve should start with an LSA of 104°. Of course for a serious race engine, that would be the starting point for testing with a few cams.
What is your valve to piston clearance as tested with modeling clay? Did not do that? No worries. Closest approach is about 15° to 10° BTDC and ATDC. Set the engine at the #1 15° BTDC and put a dial indicator on the #1 exhaust retainer. Rotate the rocker to open the valve carefully until the valve contacts the piston. Try 10° BTDC. Then rotate to 10° ATDC to measure the intake clearance. Then rotate to 15° ATDC. This should tell your minimum clearances and indictate if and by how much you can increase valve lift. IMHO this is a big limiting factor for your engine which is fairly easily remedied if you have adequate valve to piston clearance. Higher ratio rockers will open up the flow. The cam is expensive and requires some teardown to replace. If you start with 1.5:1 rockers, going to 1.6:1 rockers will get your lift up to 0.512". Spring coil bind and seat/open pressure may require a spring change. Also retainer to seal clearance would need to be checked. 0.512" gets you into more modern build spec and will let the heads perform. Stepping up on the intake rockers to 1.65:1 ratio with 1.6:1 on the exhaust would likely give more performance. Intake lift would then be 0.528". This is almost 0.050" more intake lift, probably without having to remove the heads. The engine will become snappier and develop more torque. This can also be done after installing and driving the engine, just easier on the stand.
ParDaddy
Look Momma, I'm going fast
Most of what your asking is already mentioned, screen shot of the cam specs, where the heads came from and thats for a Magnum engine so the stock rockers are 1.6 to start...
Furthermore, assuming at this point you haven't read any of the comments, it's going in my 2500 Ram, so I wasnt going crazy knowing I'll be towing and such. Besides, this way allows me to change intake and rockers to find the best combo should this not satisfy...
I know I have high comp flat top pistons with the relief cut outs for my valves (10.5-1adv. comp), 62cc heads...
I figure if my cam is the limiting factor I'll never blow it..
...and thanks for your input! To many people "know it all" these days and come off like an *** clown..
I try to remain teachable..
Dale Davies
Well-Known Member
OK. I did not see the rest of the cam specs. Doing this off "smart phone" which these days is like a mentalpause mother-in-law. So factory 1.6 rockers and the cam gives 0.480" lift. If you find 1.7:1 rockers, that will bring lift up to 0.510". Not excessive but will aid torque for towing. These days 0.500" is kind of minimal, with many builds in the 0.550" to 0.625" range. For those to perform you need good flowing heads.
Try watching David Vizard Powertec 10 youtube videos. He has a wealth of information gained over a lifetime in the racing and high performance arenas. Some do not agree with his opinions and some get pissy because a lot told is applied at the time to Chev or Ford.
A thought on that; before a farmer goes to cut hay for the critters, he does not go through the field cutting and collecting all the sticks. He goes and cuts the hay.
Before baleing the hay, he does not pick the sticks out. He just bales the hay.
When he goes to feed the critters he does not pick the sticks out. He trusts the critters to eat the hay and spit the sticks out.
When it comes to information presented, eat the hay and spit the sticks out.
Try watching David Vizard Powertec 10 youtube videos. He has a wealth of information gained over a lifetime in the racing and high performance arenas. Some do not agree with his opinions and some get pissy because a lot told is applied at the time to Chev or Ford.
A thought on that; before a farmer goes to cut hay for the critters, he does not go through the field cutting and collecting all the sticks. He goes and cuts the hay.
Before baleing the hay, he does not pick the sticks out. He just bales the hay.
When he goes to feed the critters he does not pick the sticks out. He trusts the critters to eat the hay and spit the sticks out.
When it comes to information presented, eat the hay and spit the sticks out.
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MopaR&D
Nerd Member
Do you know what head gaskets were used and if the pistons ended up below deck at all? Reason I asked is I had a 360 with similar combo as yours; small Lunati Voodoo cam (213/220 @ .050") and a measured 10.4:1 compression with iron Magnum heads. It lasted about 30k miles but I always had issues with pinging; finally one day it busted a ring land and cracked the cylinder wall when I floored it to pass someone on the freeway. In hindsight I should have been more on-the-ball with ignition timing, should've modified the advance curve for less total and more initial and eased up on the vacuum advance. I'd just hate for someone else to go through the same scenario.
ParDaddy
Look Momma, I'm going fast
I did not measure how far they are, but very little if any.. it'll be tuned and run off the computer in my 99 ram..
My question to you is, during the initial install of the valve train, dropped the new roller lifters in, bolted the heads on, new stock 9.601 pushrods, stock rockers... After putting the heads w/lifters in I dumped break in oil down the belly and ran the oil pump... Now as I'm installing the pushrod/rockers they seem to be opening valves that should be closed??
Am I missing something?
If you primed the oil system without the pushrods in, you maxed out the lifter plungers. Be very very careful when you tighten down the rockers.
ParDaddy
Look Momma, I'm going fast
You nailed it, I hadn't put them all on our let them that tight.. hand tightened them one handed ratchet-ish, then turned my motor several times by hand. As they loosened up I tightened them down..
Now I'm not getting oil up top, thru the pushrods.. gonna have my Son run the drill while I turn the motor...
Somebody correct me if I'm wrong on this.
But the LA motor oils through the number two and number four cam journal to the heads to the passage from the cam to the rocker arm shaft.
The Magnum oils through the lifter from the oil gallery through the push rod to the rocker arm.
So technically you should not have to crank the Magnum motor around in order to oil the rocker arms. Because the oil is coming from the gallery rather than from a hole in the cam journal.
Also isn't it possible to put those roller lifters in backward to where the oil hole on the lifter is pointing away from the gallery.
ParDaddy
Look Momma, I'm going fast
Thru the hydraulic lifters, up the push rods is my understanding.. running the oil pump "should" give me oil up top ain't?
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