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Re: Old 318 with new magnum heads...yay or nay? [Re: BulletBob] #1180324 02/18/12 02:20 PM 02/18/12 02:20 PM
Joined: Jan 2003 Posts: 4,323 NY NY 3 340duster340 master
340duster340 master 3 Joined: Jan 2003 Posts: 4,323 NY NY	why not just get a mag318 core and use that 1966 Dart GT ...down to only 1 mopar for the first time in 15 years!

Re: Old 318 with new magnum heads...yay or nay? [Re: CrAlt] #1180325 02/18/12 05:04 PM 02/18/12 05:04 PM
Joined: Jan 2003 Posts: 16,123 Grand Haven, MI patrick I Live Here
patrick I Live Here Joined: Jan 2003 Posts: 16,123 Grand Haven, MI	Quote: Why not just keep it simple and swap on some '302 swirl port heads? Everything you have now will bolt up. No fancy intake or manifolds needed. They are already set up for unleaded gas. And they flow better then the old 318 heads. Look for them on a 85 or later M-body with a 2bbl or a TBI truck engine. Magnum heads are better but if you are keeping the motor stockish i dont think they are worth all the extra crap you have to do to make them fit. 302's don't flow any better than old 318 heads. they have better, smaller chambers for a little more compression... mag heads and a cam in the 208@.050 and .3-.32" lobe lift makea a very pleasant and potent combo...you'll need different valve springs. hughes #1110 with their matching retainers work well. 1976 Spinnaker White Plymouth Duster, /6 A833OD 1986 Silver/Twilight Blue Chrysler 5th Ave HotRod SOLD!* 2011 Toxic Orange Dodge Charger R/T 2017 Grand Cherokee Overland 2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)

Re: Old 318 with new magnum heads...yay or nay? [Re: 340duster340] #1180326 02/18/12 05:23 PM 02/18/12 05:23 PM
Joined: Dec 2005 Posts: 9,719 Home S SRT6776 I hate internal combustion engines!
SRT6776 I hate internal combustion engines! S Joined: Dec 2005 Posts: 9,719 Home	Quote: why not just get a mag318 core and use that X2 may as well just change motors. They gotta be giving away 5.2 and even 5.9 Magnums by now. I'd even look into early 03-08 non VCT 5.7L Hemi's, even if just for reference sake.

Re: Old 318 with new magnum heads...yay or nay? [Re: 340duster340] #1180327 02/18/12 09:08 PM 02/18/12 09:08 PM
Joined: Nov 2003 Posts: 10,228 Colleyville 3hundred I Live Here
3hundred I Live Here Joined: Nov 2003 Posts: 10,228 Colleyville	Quote: why not just get a mag318 core and use that I agree, the 318 mag is a sweet little package that blows the doors off the older ones. Mileage is good as well, wife's 318 magnum Ramcharger knocks down 20 MPG on the road. 318 mag is a virtual bolt in, very easy swap, old engine mounts are there, transmission pattern is the same, sealing is greatly improved over the old engine. Robert '68 Fury Convertible '69 300 Convertible '15 Durango 5.7 Hemi '16 300 S Hemi

Re: Old 318 with new magnum heads...yay or nay? [Re: 3hundred] #1180328 02/19/12 12:33 AM 02/19/12 12:33 AM
Joined: Mar 2005 Posts: 1,630 North Central Florida E eightlitermopar OP top fuel
eightlitermopar OP top fuel E Joined: Mar 2005 Posts: 1,630 North Central Florida	Quote: Quote: why not just get a mag318 core and use that I agree, the 318 mag is a sweet little package that blows the doors off the older ones. Mileage is good as well, wife's 318 magnum Ramcharger knocks down 20 MPG on the road. 318 mag is a virtual bolt in, very easy swap, old engine mounts are there, transmission pattern is the same, sealing is greatly improved over the old engine. Robert So the 904 would bolt right up? I know the 518 would be sweet, but you can see where this is going. A simple regasket turns into...."well, while I am here, I might as well..." I get carried away pretty quickly. eightlitermopar Mopar or no car

Re: Old 318 with new magnum heads...yay or nay? [Re: eightlitermopar] #1180329 02/19/12 12:58 AM 02/19/12 12:58 AM
Joined: Jul 2003 Posts: 6,167 Maryland GO_Fish master
GO_Fish master Joined: Jul 2003 Posts: 6,167 Maryland	904 will bolt up to a 5.2 Mag just fine (if you are converting the Mag to carb'd instead of OE injection). If you want to keep the Mag injected, You'll need to notch the 904 bell housing to allow fitment (of a crank position sensor???). Scott B. "I'm a self-made man... I started with nothing, and I still have most of it!" 68 360 rusty B'cuda 'vert (GO Fish)13.59@ 98.72 mph 69 340 GTS stock 14.18@ 95.60 mph 01 5.9L Ram 1500 Quad Cab 4x4 01 3.5L 300M 16.23@ 86.97 mph

Re: Old 318 with new magnum heads...yay or nay? [Re: Dakota_Don] #1180330 02/19/12 11:59 AM 02/19/12 11:59 AM
Joined: Jan 2003 Posts: 1,586 Tampa, FL tpabayflyer pro stock
tpabayflyer pro stock Joined: Jan 2003 Posts: 1,586 Tampa, FL	Quote: go for it.. it will be like a new motor Understatement of the year!!! I did this swap to a 70 318 motor and it was incredible how much more power it had compared to the stock heads. This was a 52,ooo mile original 2 barrel engine. Now I did use home ported mag heads with headers and a .450 lift cam but that little 318 woke right up and sounded pretty mean with a nice angry burble from the exhaust!!! Do it! TBF 71 Challenger 528 Hemi project 09 Gr Cherokee 5.7 hemi in da house!!

Re: Old 318 with new magnum heads...yay or nay? [Re: eightlitermopar] #1180331 02/19/12 07:40 PM 02/19/12 07:40 PM
Joined: Dec 2005 Posts: 1,151 Cruising! Q QuickDodge super stock
QuickDodge super stock Q Joined: Dec 2005 Posts: 1,151 Cruising!	According to some earlier posts on this website, it's possible to redrill the magnum heads to use the LA intake manifold. If I recall correctly, the ports in the LA intake are a slightly different size or shape than the ports in the magnum heads. Because of this difference, it's best to use the aftermarket intake designed for the magnum heads.

Re: Old 318 with new magnum heads...yay or nay? [Re: QuickDodge] #1180332 02/19/12 09:11 PM 02/19/12 09:11 PM
Joined: Oct 2005 Posts: 6,048 Back home in PA B BulletBob master
BulletBob master B Joined: Oct 2005 Posts: 6,048 Back home in PA	The ports are in the same place. If you sit the LA intake gaskets on the Mag heads they fit perfect only the holes are different. The ports being different is wrong except for they flow better. I've got 3 of those incorrect intakes that have been riding for years now & haven't had a problem yet out of any of them. I've own both the Crosswind & RPM Air-gap & have used the MP pieces too they all work fine Alot of the guys here in the past used to bash & say the port crap thing about the Crosswind because the Edelbrock is supposed to be King. The Edelbrock isn't that friendly using LA stuff with it. No one makes a correct bypass hose to use it & if you have A/c you Can't use it unless you Change it to serpentine drive. If you need pics I have both intakes to compare

Re: Old 318 with new magnum heads...yay or nay? [Re: BulletBob] #1180333 02/19/12 10:33 PM 02/19/12 10:33 PM
Joined: Jul 2003 Posts: 6,167 Maryland GO_Fish master
GO_Fish master Joined: Jul 2003 Posts: 6,167 Maryland	Intake ports are about the same between LA and Magnum. Maybe you are thinking about the exhaust ports? There is a difference between LA and Magnum exhaust ports... bolt pattern is the same, but the floor of the Magnum port is raised for better flow. If trying to mate LA exhaust manifolds or headers to Magnum heads, I'd suggest using "Remflex" gaskets to make sure they seal at the bottom of the port. Scott B. "I'm a self-made man... I started with nothing, and I still have most of it!" 68 360 rusty B'cuda 'vert (GO Fish)13.59@ 98.72 mph 69 340 GTS stock 14.18@ 95.60 mph 01 5.9L Ram 1500 Quad Cab 4x4 01 3.5L 300M 16.23@ 86.97 mph

Re: Old 318 with new magnum heads...yay or nay? [Re: GO_Fish] #1180334 02/19/12 10:41 PM 02/19/12 10:41 PM
Joined: Oct 2005 Posts: 6,048 Back home in PA B BulletBob master
BulletBob master B Joined: Oct 2005 Posts: 6,048 Back home in PA	I never ran into that problem. i only did one with stock LA manifolds & I used header gaskets on those manifolds when I did

Re: Old 318 with new magnum heads...yay or nay? [Re: BulletBob] #1180335 02/20/12 08:03 AM 02/20/12 08:03 AM
Joined: Mar 2005 Posts: 1,630 North Central Florida E eightlitermopar OP top fuel
eightlitermopar OP top fuel E Joined: Mar 2005 Posts: 1,630 North Central Florida	So what about the cast iron heads? Did they have problems with castings for a while? It seems good, but I have to remember that a lot of these big full size vans or trucks with the magnum motor are in the junkyard for a reason. If so, what to look for, avoid, etc. eightlitermopar Mopar or no car

Re: Old 318 with new magnum heads...yay or nay? [Re: eightlitermopar] #1180336 02/20/12 09:22 AM 02/20/12 09:22 AM
Joined: Nov 2003 Posts: 10,228 Colleyville 3hundred I Live Here
3hundred I Live Here Joined: Nov 2003 Posts: 10,228 Colleyville	Quote: So what about the cast iron heads? Did they have problems with castings for a while? It seems good, but I have to remember that a lot of these big full size vans or trucks with the magnum motor are in the junkyard for a reason. If so, what to look for, avoid, etc. eightlitermopar I've heard rumors they're all cracked, just not in a critical place. My wife's truck is about to turn over 298,000 miles with no engine trouble. I pulled the 360 out of the other truck with 168,000 miles for the hemi swap, not because it was having any troubles. Robert '68 Fury Convertible '69 300 Convertible '15 Durango 5.7 Hemi '16 300 S Hemi

Re: Old 318 with new magnum heads...yay or nay? [Re: 3hundred] #1180337 02/20/12 10:56 AM 02/20/12 10:56 AM
Joined: Jan 2003 Posts: 3,920 n.e. pa. 6 65rbdodge master
65rbdodge master 6 Joined: Jan 2003 Posts: 3,920 n.e. pa.	i have seen and heard about them being cracked, but have never heard about it being a problem.

Re: Old 318 with new magnum heads...yay or nay? [Re: CrAlt] #1180338 02/26/12 03:06 PM 02/26/12 03:06 PM
Joined: Apr 2004 Posts: 526 Marilla, New York R RalleyA12 mopar
RalleyA12 mopar R Joined: Apr 2004 Posts: 526 Marilla, New York	Quote: Why not just keep it simple and swap on some '302 swirl port heads? Everything you have now will bolt up. No fancy intake or manifolds needed. They are already set up for unleaded gas. And they flow better then the old 318 heads. Magnum heads are better but if you are keeping the motor stockish i dont think they are worth all the extra crap you have to do to make them fit. You must keep things in perspective, you're only feeding 318 cubic inches, you don't need a real high CFM head, leave those for the 408 stroker crowd. Pocket ported 302's with a 1.88 intake would be the way I'd go.

Re: Old 318 with new magnum heads...yay or nay? [Re: eightlitermopar] #1180339 02/26/12 06:50 PM 02/26/12 06:50 PM
Joined: Jan 2003 Posts: 6,816 Alton, IL D Dakota_Don master
Dakota_Don master D Joined: Jan 2003 Posts: 6,816 Alton, IL	go for it , the intakes are cheap.. look for a used crosswinds or a new one. i decent 4 barrl. like a TQ or an avs..thing should run good.. i know my stock 318 ran good with this setup..

Re: Old 318 with new magnum heads...yay or nay? [Re: RalleyA12] #1180340 02/26/12 07:43 PM 02/26/12 07:43 PM
Joined: Jan 2003 Posts: 16,123 Grand Haven, MI patrick I Live Here
patrick I Live Here Joined: Jan 2003 Posts: 16,123 Grand Haven, MI	Quote: Quote: Why not just keep it simple and swap on some '302 swirl port heads? Everything you have now will bolt up. No fancy intake or manifolds needed. They are already set up for unleaded gas. And they flow better then the old 318 heads. Magnum heads are better but if you are keeping the motor stockish i dont think they are worth all the extra crap you have to do to make them fit. You must keep things in perspective, you're only feeding 318 cubic inches, you don't need a real high CFM head, leave those for the 408 stroker crowd. Pocket ported 302's with a 1.88 intake would be the way I'd go. 302's don't flow any better than open chambered 318 heads. they'll give you a better combustion chamber, hardened seats, and maybe 1/3-1/2 point compression boost, but heavily worked with 2.02's, they flow about the same on the intake (and worse on the exhaust) than factory magnums. not worth the trouble, IMHO 1976 Spinnaker White Plymouth Duster, /6 A833OD 1986 Silver/Twilight Blue Chrysler 5th Ave HotRod SOLD!* 2011 Toxic Orange Dodge Charger R/T 2017 Grand Cherokee Overland 2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)

Re: Old 318 with new magnum heads...yay or nay? [Re: patrick] #1180341 02/26/12 11:19 PM 02/26/12 11:19 PM
Joined: Jan 2003 Posts: 1,217 Endicott, NY B bnichols pro stock
bnichols pro stock B Joined: Jan 2003 Posts: 1,217 Endicott, NY	i am on my 3rd magnum headed la motor luv it!! will never go back to outdated la heads, my 76 aspen with 43k miles on it i just did the magnum head swap night and day diff woke the lil teen up sounds like a mean teen now lol go for it you waon't be sorry just make sure you have the correct length pushrods 7.625 in length with a hydraulic flat tappet

Re: Old 318 with new magnum heads...yay or nay? [Re: bnichols] #1180342 02/26/12 11:37 PM 02/26/12 11:37 PM
Joined: Jan 2003 Posts: 6,816 Alton, IL D Dakota_Don master
Dakota_Don master D Joined: Jan 2003 Posts: 6,816 Alton, IL	is that the same legnth you use on all your mag swaps?

Re: Old 318 with new magnum heads...yay or nay? [Re: Dakota_Don] #1180343 02/27/12 10:47 PM 02/27/12 10:47 PM
Joined: Jul 2003 Posts: 394 Tennessee C classof65 enthusiast
classof65 enthusiast C Joined: Jul 2003 Posts: 394 Tennessee	I think Patrick needs to speak with Donnie Quinn about whether or not the 302 head flows the same as the other 318 stuff. Much of the "advantage" of the Magnum heads is due to the 1.6 rocker ratio. Let's look at this another way. Find a set of 315 castings (273) have a decent valve job and install them. The port velocity will more than make up for the volume increase of the magnum. Anyone out there got a 318 with magnums in a 74 - 76 A body? What's your ET and what kind of fuel do you have to run? Just built a .030 over 318 with Sealed Power (el cheapo) pistons, I used the .411 - .399 stock eliminator cam out of our U/SA car, a set of 315 casting heads, a 273 HP cast iron intake, and a quick fuel 650 carb. ET 12.28 on regular pump gas. Granted it's got some gear, but that 75 Dart is HEAVY.... What I am saying is, there are several routes to the same destination, take the path with the least resistance. Oh, by the way, the valves are STOCK DIAMETER 273 jobs.... Peace, Rev. Mopar (Class of 65, 32 time National Record holder in U/SA)

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