magnum head ?

Posted By: dustpan man

magnum head ? - 12/08/08 05:14 AM

are the magnum heads off a 318 the same as the heads off a 360 i got a 75 360 i want to put them on and

are the intake manifolds different

Posted By: 4speeds4me

Re: magnum head ? - 12/08/08 05:39 AM

The 318 and 360 Magnum heads are the same. Bolting them onto a 75 360 isn't TOTALLY straightforward, though. The Mags oil the rockers through the pushrods and have individual rockers. There are conversion pieces readily available.

The intakes are different, but Mag heads can be redrilled to accept LA intakes, or you can use a Magnum specific intake, I believe available from MP, Edelbrock, or the Professional Products "Crosswind".

Posted By: dustpan man

Re: magnum head ? - 12/08/08 05:45 AM

u think i can use the push rods from the magnum motor do u would u get them and use them

Posted By: OzHemi

Re: magnum head ? - 12/08/08 06:17 AM

The magnums use roller lifters as well, so the push rods will not be the correct length with a normal oil through the pushrod non roller lifter.

Posted By: RapidRobert

Re: magnum head ? - 12/08/08 06:24 AM

The MP pushrods for this conversion may end up being too short, mock everything up before you make a decision on ordering pushrods.

Posted By: dustpan man

Re: magnum head ? - 12/08/08 06:31 PM

how much would they go for there in a u pull junkyard i can get them perty cheap do u think i should pull them if i deside not to use them

Posted By: Neil

Re: magnum head ? - 12/08/08 06:42 PM

Make sure they aren't cracked. If you buy them from a junkyard make sure they will allow you to return them if they are damaged.

I looked at a set on a 318 a few weeks ago and can't believe how small the intake ports are. The pushrod bump was huge and it didn't look like you could remove a whole lot of it before you'd break thru. My dad was looking for a set to put on a LA 360, but they don't look like they could flow a lot of air stock.

Posted By: MarkZ

Re: magnum head ? - 12/08/08 08:52 PM

Quote:

My dad was looking for a set to put on a LA 360, but they don't look like they could flow a lot of air stock.

They do, more than a stock J head could ever muster.

I had a lengthy conversation with another board member here and he mentioned Mag heads off of a 318 being less prone to cracking than those off of 360s. Makes sense when you think about it. Maybe the 360s were ran leaner to pass emissions standards?

I have a set off of a 100k+ 318 Mag and they came back crack free.

Posted By: 540challenger

Re: magnum head ? - 12/08/08 08:56 PM

Quote:

Quote:

My dad was looking for a set to put on a LA 360, but they don't look like they could flow a lot of air stock.

They do, more than a stock J head could ever muster.

I had a lengthy conversation with another board member here and he mentioned Mag heads off of a 318 being less prone to cracking than those off of 360s. Makes sense when you think about it. Maybe the 360s were ran leaner to pass emissions standards?

I have a set off of a 100k+ 318 Mag and they came back crack free.

I think the 318 heads were produced in a different foundry then the 360 head

Posted By: scratchnfotraction

Re: magnum head ? - 12/08/08 09:30 PM

you will need the oil through flat tappets and the hollow conversion pushrods from MP/dealer to run mag heads on a older LA engine block

these 2 things are a must to run mag heads on a non-mag LA block

the intake has options as mentioned above

if your block is a pre-mag LA roller block then you can use the mag roller lifters and stock pushrods and mag heads

Posted By: GoDartGo

Re: magnum head ? - 12/08/08 10:08 PM

wadda'bout head bolts?

Posted By: 540challenger

Re: magnum head ? - 12/09/08 01:18 AM

Head bolts are different also You can get them anywhere. Just ask for head bolts for any mangum engine and they will work or you can get them thru mopar, manicci, "spelled wroung"

Like mention in the post above the tappets need to be for pusrods oiling but must after market lifters comes this way if you have an aftermarket came chances are you have them already just look for the oiling hole in the middle of the lifter.

Posted By: scratchnfotraction

Re: magnum head ? - 12/09/08 01:48 PM

yes,stock head bolts will work for the mag heads on an LA block

Posted By: dgc333

Re: magnum head ? - 12/09/08 04:37 PM

Quote:

The MP pushrods for this conversion may end up being too short, mock everything up before you make a decision on ordering pushrods.

The conversion push rods are 7.625" long. In my application I wound up odering 7.650" long push rods. This length was a stock length for some other application so they were off the shelf from Summit.

Posted By: dustpan man

Re: magnum head ? - 12/10/08 04:49 AM

are the valve covers the same

Posted By: 540challenger

Re: magnum head ? - 12/10/08 12:45 PM

Quote:

are the valve covers the same

No the magnum and La covers are different

Magnum have ten bolt covers

LA 5 bolt

Plus the cover gasket is shaped a little different from magnum to la.

However many guys have been able to install LA covers on Magnum heads with no leaks.

Posted By: dmerc

Re: magnum head ? - 12/10/08 01:16 PM

Quote:

are the valve covers the same

Here is a pic of Magnum covers on my car. I think they look pretty good.

Posted By: dgc333

Re: magnum head ? - 12/10/08 01:18 PM

And here is a picture of LA covers on magnum heads.

Thesse have been on there for approximately 25k miles now and no signs of a leak.

Posted By: Devil

Re: magnum head ? - 12/10/08 03:14 PM

I like these valve covers, I plan on putting these on my RamCharger when I get the chance. Got them for a really good deal too!

But as was said before, LA style valve covers can fit.

Ryan

Posted By: 2boltmain

Re: magnum head ? - 12/10/08 10:23 PM

So for a magnum head conversion set up, what are the costs for the valvetrain items for a .500" lift hyd flat tappet cam? - lifters, pushrods, rocker arms and studs. Can regular run of the mill small blk chevy rocker arms be used? Been comparing an Engine Quest magnum head conversion to a set of ready to run Edelbrock LA heads. I think after the conversion is complete with the magnum type heads the cost would be comparable to staying with the LA setup but with new Ebrocks.

Posted By: patrick

Re: magnum head ? - 12/11/08 01:56 AM

Quote:

So for a magnum head conversion set up, what are the costs for the valvetrain items for a .500" lift hyd flat tappet cam? - lifters, pushrods, rocker arms and studs. Can regular run of the mill small blk chevy rocker arms be used? Been comparing an Engine Quest magnum head conversion to a set of ready to run Edelbrock LA heads. I think after the conversion is complete with the magnum type heads the cost would be comparable to staying with the LA setup but with new Ebrocks.

lifters you probably already have if it's an aftermarket cam, just about every aftermarket cam manufacturer for the last 10-15+ years (except maybe MP) spec the same lifter for mopar and AMC, so there really isn't any "additional" cost

for .5" lift hydraulic, I'd just use stock magnum rockers, should be able to find some used for under $50, or new, IIRC they're about $80 total from MP.

pushrods, I'd mock everything up and measure how long of a pushrod you need. the MP pushrods, if they're the right length, are ~$40. if they're not, I'm sure there's a "shelf" small block chev pushrod length from summitracing or jegs that'll work for under $100.

earlier this year, Carolina Machine Engines quoted me $650 for a set of enginequest 318B's (LA intake bolt pattern so you don't have to buy a new intake), with OEM spec 1.92/1.625 valves, 3 angle valve job, mag keepers, and OEM spec GM 3100 springs and retainers set up at 1.65 IH (should provide adequate clearance for ~.520" lift, and those springs are 330-360lb/in rate, and about 95lb seat pressure at that IH)) for $650+ ship

new mag head bolts (different length than LA) are less than $20 from MP last I checked.

use the good neoprene intake manifold gaskets and you can use LA covers....

so adding all this up, you have $650 for heads, probably ~$40-100 for pushrods, and $20? (for used on fleabay) to $120 for OEM mag rockers, and $20 for head bolts for a total of $730-890 for a mag head conversion + ship. you won't find eddie LA heads new for less than $1300 a pair, and then you need special length ARP head bolts, IIRC that are ~$100/set, so you're approximately 50%-65% the cost of new eddie heads for new mag heads.

CME quoted me $850/pr for EQ 318B's with small block chev valves that are .1" longer than stock and springs set up for a .550ish lift hydraulic roller and a 5 angle valve job...adding the extra $200, you're still at <75% the cost of eddle LA heads.

Posted By: challenger73400

Re: magnum head ? - 12/11/08 02:32 AM

Keep in mind the rocker ratio is 1.6 for stock magnum rockers so you want to make sure the springs and clearances are up to the extra valve lift.

Posted By: 2boltmain

Re: magnum head ? - 12/12/08 01:31 AM

Thanks a bunch for the $$ info. I have a new perspective now. I was not aware of the heads available that low.

Posted By: dustpan man

Re: magnum head ? - 12/12/08 05:46 AM

there alot lower for me cuse im geting them out of a junk yard

Posted By: scratchnfotraction

Re: magnum head ? - 12/12/08 01:26 PM

OH! YEA!!,the junk yard jewel....SWWEEETT!!!

run what ya brung

go junk yarding when its broke

Posted By: edbux

Re: magnum head ? - 12/12/08 10:54 PM

Quote:

So for a magnum head conversion set up, what are the costs for the valvetrain items for a .500" lift hyd flat tappet cam? - lifters, pushrods, rocker arms and studs. Can regular run of the mill small blk chevy rocker arms be used? Been comparing an Engine Quest magnum head conversion to a set of ready to run Edelbrock LA heads. I think after the conversion is complete with the magnum type heads the cost would be comparable to staying with the LA setup but with new Ebrocks.

with the Magnum heads and their 1.6 rocker arm ratio, that puts your lift at .533. Now you're into valve springs and things associated with them. There really isn't a low cost spring for the Magnum unless you go with the GM 3100 springs mentioned above.

Posted By: 2boltmain

Re: magnum head ? - 12/12/08 11:51 PM

Well my already purchsed and stored under my bed cam is an Engle 230 deg @.050 with .514" lift. I guess Id have to spend the $850 for heads with compatible springs. Still not a bad deal. Those heads, above cam, KB107 pistons, 3000 stall verter and 3.91s would make for a great street set up in my Demon....Yes?????.

Posted By: dustpan man

Re: magnum head ? - 12/14/08 05:36 AM

ya man i love the upull junk yards u get good stuff reall cheap