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Magnum head conversion #170709 12/19/08 03:34 PM 12/19/08 03:34 PM
Joined: May 2004 Posts: 1,522 Ste-Sophie, Quebec, Canada W Wedgeman OP pro stock
Wedgeman OP pro stock W Joined: May 2004 Posts: 1,522 Ste-Sophie, Quebec, Canada	In a recent article, i read that in order to take full advantage of the magnum heads, and have a cam beyond .500 lift, you need to have longer valves and machine the heads......along with longer springs.Is this true at all ? what machinage do they need ? Can I put the roller lifters of the magnum engine in a LA block ? Dan

Re: Magnum head conversion [Re: Wedgeman] #170710 12/19/08 03:46 PM 12/19/08 03:46 PM
Joined: Apr 2007 Posts: 2,826 NY usa 5 540challenger master
540challenger master 5 Joined: Apr 2007 Posts: 2,826 NY usa	Quote: In a recent article, i read that in order to take full advantage of the magnum heads, and have a cam beyond .500 lift, you need to have longer valves and machine the heads......along with longer springs.Is this true at all ? what machinage do they need ? Can I put the roller lifters of the magnum engine in a LA block ? Dan I haven't heard anything about needed longer valves or springs but the machine of the guides is requires around the .510 lift range b/c of the guide to retainer clearance or lack of. The springs will have to be changed out must likly has the stock ones are not that great. they are must likely not going to have enough spring pressure. As for the roller lifts it depends on the year block last few years of the LA family block has the provison to use "factory sytle" roller lifters . This cuts the cost down. Last edited by 540challenger; 12/19/08 03:47 PM.

Re: Magnum head conversion [Re: 540challenger] #170711 12/19/08 04:24 PM 12/19/08 04:24 PM
Joined: Apr 2004 Posts: 1,396 Mass dgc333 pro stock
dgc333 pro stock Joined: Apr 2004 Posts: 1,396 Mass	[quote I haven't heard anything about needed longer valves or springs but the machine of the guides is requires around the .510 lift range b/c of the guide to retainer clearance or lack of. The springs will have to be changed out must likly has the stock ones are not that great. they are must likely not going to have enough spring pressure. As for the roller lifts it depends on the year block last few years of the LA family block has the provison to use "factory sytle" roller lifters . This cuts the cost down. Everything I have read its .525" that is the limit but its certainly prudent to check on anything over .5" I have magnum heads on an LA block with a .509/.512" lift cam and there was clearance between the bottom of the retainer and the top of the valve seal when I checked. I used retainers from a 2.2 mopar 4cyl and it may be different with other retainers. If you are going to have a valve job on the heads it wouldn't be a bad idea to just cut the guides down so you aren't so limited on lift. But, the head flow numbers I have seen on magnum heads you don't gain anything above .5" with a stock head anyway. Dave Clement Pembroke, MA 03 PT Cruiser GT Turbo 99 Dakota SLT+ CC 4x4 68 Barracuda sport coupe http://home.comcast.net/~dgc333/

Re: Magnum head conversion [Re: dgc333] #170712 12/19/08 04:30 PM 12/19/08 04:30 PM
Joined: Apr 2007 Posts: 2,826 NY usa 5 540challenger master
540challenger master 5 Joined: Apr 2007 Posts: 2,826 NY usa	Quote: [quote I haven't heard anything about needed longer valves or springs but the machine of the guides is requires around the .510 lift range b/c of the guide to retainer clearance or lack of. The springs will have to be changed out must likly has the stock ones are not that great. they are must likely not going to have enough spring pressure. As for the roller lifts it depends on the year block last few years of the LA family block has the provison to use "factory sytle" roller lifters . This cuts the cost down. Everything I have read its .525" that is the limit but its certainly prudent to check on anything over .5" I have magnum heads on an LA block with a .509/.512" lift cam and there was clearance between the bottom of the retainer and the top of the valve seal when I checked. I used retainers from a 2.2 mopar 4cyl and it may be different with other retainers. If you are going to have a valve job on the heads it wouldn't be a bad idea to just cut the guides down so you aren't so limited on lift. But, the head flow numbers I have seen on magnum heads you don't gain anything above .5" with a stock head anyway. is the 509/512 lift base on 1.5 rockers or 1.6 Another thing to remeber when picking a cam magnums have 1.6 rockers stock.

Re: Magnum head conversion [Re: 540challenger] #170713 12/19/08 04:35 PM 12/19/08 04:35 PM
Joined: Oct 2003 Posts: 21,345 Marysville, O-H-I-O 70Cuda383 Too Many Posts
70Cuda383 Too Many Posts Joined: Oct 2003 Posts: 21,345 Marysville, O-H-I-O	and if you're going to port them for cams over .500 lift, be careful, these heads like to crack. Photobucket sucks

Re: Magnum head conversion [Re: 70Cuda383] #170714 12/19/08 04:54 PM 12/19/08 04:54 PM
Joined: May 2004 Posts: 1,522 Ste-Sophie, Quebec, Canada W Wedgeman OP pro stock
Wedgeman OP pro stock W Joined: May 2004 Posts: 1,522 Ste-Sophie, Quebec, Canada	This comes from the article in Mopar Enthusiast,DEc 2008 issue..... Yeah.....cracks are the only thing holding me back right now,,,,,,what to do ?????

Re: Magnum head conversion [Re: Wedgeman] #170715 12/19/08 07:43 PM 12/19/08 07:43 PM
Joined: Jan 2005 Posts: 12,419 Kalispell Mt. H HotRodDave I Live Here
HotRodDave I Live Here H Joined: Jan 2005 Posts: 12,419 Kalispell Mt.	They were cracked a lot right from the factory, I have fooled with magnums a bunch and never seen a cracked one cause any problem. I have only re-used one pair with cracks but I have pulled many from running good motors and was suprised to find cracks. They are caused from the induction hardning process aparently. 318 tend to have less cracks, they are the same casting as a 360 mag but made in different factorys so mabey that is the reason or it could be the lower compression 360 makes more ex heat If the cracks really bother you get some EQ or RHS magnums, they have pressed in hardned seats to prevent cracking. I am not causing global warming, I am just trying to hold off a impending Ice Age!

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