magnum or pre-magnum that is the ?

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DARTGAME

DARTGAME

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what should I use? I have a 273/904 combo right not w/400k on the motor. should I go magnum w/ air gap manifold or pre magnum w/ performer manifold? Can a 904 be bolted to magnum motor? any thoughts would be apreciated.
 
IF you are talking converting.....yes, Magnum is the best bolt on power adder. Caution...You do need provisions to oil through the push rods, and if your block is a hyd flat tappet you canNOT go with a hyd roller cam (like production magnums have). I'm converting an 87 360 to Magnum and found that info out. PLAIN Magnum heads are hard to find unless you have a donor or go with the R/T heads, Chrysler stopped making Magnum heads and are using the R/T heads on all the crate engines..trust me the price reflects it....
you should be able to bolt the 904 up to it though....
 
OOPS...I'm not sure if the Magnum heads will bolt on to a 273, I know the they are interchangeable between the 318 and 360...

Sorry!! 8) :) :salut:
 
thanks for the info. I was thinking magnum from a wrecked dak rt. and use air gap manifold. just wanted to know what would be a better power
maker. do I still need the b&m flexplate for the balance?
 
I can't believe they have stopped manufacturing magnum heads considering all the engines out there that are still under warranty and the 360 just stopped being used in trucks in 04. MP may make the switch to R/T heads on the crate engines but I haven't seen anywhere that that is happening. They are (4) 360 crate motors with one already having the aluminum R/T head on it.

There are (5) choices of carburetor manifolds for that fit the magnum heads.

Mopar Performance M1 series has a dual plane and a single plane available.

Professional Products has two dual planes. One similar to the Edelbrock Performer and one like the RPM Air-Gap.

The magnum engine is externally balanced but the balance is different than the old 360 LA. You will need to get the flex plate or convertor that is specific for a magnum engine.

And of course Edelbrock has the RPM Air-Gap.

I just purchased the Professional Products Cross-Wind (Air-Gap knock off) for my magnum head LA 360 I am building. I figured the $130 I saved over the Air-Gap can be put to use for other things.

Also, you certainly can go hydraulic roller in a LA block. Can't use factory parts but roller lifters from Comp Cams, Crane or others can be used.
 
I heard the same thing about the Magnum heads getting the ax. I dont remember from who but he worked for either Mopar Perf. or one of there big parts dealers. Also the Magnum heads part numbers have been replaced with the R/T heads.
 
i want to mate the magnum to my 904. what should I use if the b&m won't work. Can I use my accessories like p/s,alt, a/c w/ same brackets? The waterpump lower hose on drivers side problem?sorry for all the lame ?s.
 
If your converting an LA engine, it should remain balanced as such, the main difference between the 2 is from the top end, shortblock stays the same. If anyone needs there was an article in Mopar Muscle that explains the conversion, I can photocopy and send it to you. I can see if I can scan them for email...have to check. BUT you must have oiling through the pushrods, that is Magnum specific!!!!!!!
 
B&M does make a flex plate. You can get it from summit racing or mancini. If the motor came from a truck you'll need an electric fuel pump and a new water pump. The magnum trucks water pump turn the wrong way.
 
AdamR said:
B&M does make a flex plate. You can get it from summit racing or mancini. If the motor came from a truck you'll need an electric fuel pump and a new water pump. The magnum trucks water pump turn the wrong way.
Click to expand...

A LA water pump does not fit the magnum engine front cover. You will need to swap the front cover from the 273 over and still use the electric fuel pump unless you change the cam to a long snout one and add the fuel pump eccentric.

Also, the accessory mounts on the magnum heads are not exactly in the same place so you will need to modify / fabricate the brackets for existing accessories to fit.
 
thanks for all the info. I guess its alot of work to go magnum. maybe just go pre magnum instead. I think anything at this point is going to be better than what I got.
 
I think the Magnum is well worth having to swap water pump and flex pates.
 
Why are you looking to change water pump and flex plates????? If you are converting an LA all you are switching is the heads and intake,taking the 273 hasn't been in production for a while, just check for the oiling ov the valve train. It should be balanced as an LA, flex plate should stay the same as well as water pump. Look at the crate engines. They are the same architecture as an LA engine just has the magnum specific parts. Now, Yes, PRODUCTION Magnums that are in the trucks do have a different timing chain cover and water pump. If any one wants, email me and I will give you the name and number of the guy who I talked to, he is a Performance Specialist at a Dodge dealer or call Mopar Performance personally and I can scan my article from Mopar Muscle, who converted an LA engine, and email it to ya'll!!! :salut:
 
i want to take my 273 out and in turn place a magnum 5.9L out of a dak r/t. wanted to know if worth it or not. I have a 360 but it is stock and needs rebuilding. I know I can swap that, but was curious about the magnum due to all the advantages it has. I don't think the flex plates(stock or b&m unit ) will work but thats my opinion. this car is my driver so thats the reason for all the ?s. looking for the easy swap thats all.
thanks for all your help.
 
The B&M flexplate is balanced just for the magnum motors.

The water pump from your 273 will work but you'll need an intake also.
 
Edelbrock also has magnum heads available, theyre pretty new. If you want to go magnum you can also just get a crate engine, maybe a short block and choose the heads u want, or get it all in the long block and get the intake u need. I choose the simpler route and went pre magnum I think its cheaper too, and u can stroke it out and get a lot of power. Does the magnum use the same stroker parts as the pre magnum?
 
last question, can I use my pulleys wih magnum or should I try to use junkyrd mix&match. I got a LA360 and 440 already but can get a magnum. I have no daily driver other than my dart right now so looking to do it in a weekend.
 
DARTGAME said:
i want to take my 273 out and in turn place a magnum 5.9L out of a dak r/t. wanted to know if worth it or not. I have a 360 but it is stock and needs rebuilding. I know I can swap that, but was curious about the magnum due to all the advantages it has. I don't think the flex plates(stock or b&m unit ) will work but thats my opinion. this car is my driver so thats the reason for all the ?s. looking for the easy swap thats all.
thanks for all your help.
Click to expand...

I didn't see this mentioned but the oil pan on a truck motor has the sump on the back. You will need to get a car oil pan to clear the center link. The pan off the 273 will not fit.
 
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