Given a "Magnum" 318 - Possibilities?

[Guest Frank Rich]

Just when I thought everything was finally getting relatively simple...

 

I have just been literally given - free, por nada, no charge - just haul it away and its yours, a 318 "Magnum" out of a '96 Jeep Wagoneer(?) that had 51,000 miles on the clock when the owner pulled this engine out and dropped in a new 360 instead.

 

I freely confess that I know very little about the possibilities of upping the performance of these motors - I've had a stock 318 in a Dakota pickup before, and it was one very tough and reliable motor, but that was a bone-stock work vehicle that went for 300,000 miles with nothing but good, regular maintenance. Never went into that motor except once to replace the timing chain, changed oil ever 3K miles, R&R'ed the tranny (5-speed) and differential fluid every 30,000 miles, and it ran almost as well at 300,000 miles as it did when it was new.

 

Now my question for you Mopar guys is this - does this motor have any potential for real power and performance, is there a good selection of performance parts/upgrades for this motor, or should I be looking for a good swap for an older motor with more possibilities? This is a "freebie", and I don't want to look a gift horse in the mouth, and I have a second 260Z body shell sitting in storage, looking for a motor - but at the same time, I don't know what the possibilities are for this motor - I'm not as up on Mopar as I might be, so any advice, opinions, help etc. will be greatly appreciated.

Thanks.

 

"Lead me not into Temptation, I'm getting there just fine on my own!"

 

Frank

[Guest Anonymous]

The 318 is an excellent motor IMHO. I'm not familiar with 360's but all of the 340 stuff (heads and intake) could be bolted on. I'm assuming the 360 stuff might fit the 318, but don't know for fact. Any of those motors would make a nice swap, its weight wise between the lightweight ford V8 and the Heavy Chevy.

 

Regards,

 

Lone

[Guest Anonymous]

The 318 magnum is a great motor. I'm pretty sure you can use all the 360 magnum stuff. The 318 has a smaller bore so big valve magnum heads will work. The 1.88 intake should be fine for a 318 though. with a 3.31 stroke the motor should rev pretty good. you could use the fuel injection if the motor came with it or you could just use a carb. good luck

[Guest Anonymous]

actually lone if its a magnum none of the pre "maganum stuff will work with it other than the exception of crank, rods, pistons, and other bottom end components although the oil pump might be different too (not sure) the differance betwen the magnum and the LA block s the heads are different, they went to a roller lifter setup, and the the way the heads are oiled. the last one is the big reason why pre magnum heads can't be swapped. it doesnt matter though anyway, the magnum head casting outflow all other production small block heads except for the w2 and up style but then again those are race heads

[Guest John Adkins]

Pre-Magnum intake manifolds can be used with Magnum heads if the bolt holes are elongated; the manifold bolts on Magnum heads have a different angle than the pre-magnum.

 

Magnum heads will work on a pre-Magnum block if you use change the pushrods and lifters to those that allow oiling through the pushrods. Pre-Magnum heads won't work on the Magnum block because the Magnum blocks don't have the oil passage drilled for valvetrain oiling.

 

Other than than that, pretty much everything else interchanges....

[Guest Anonymous]

Thanks for the correction, I didn't know the magnum's made those changes. I used that darn word 'ass u me' doh.. Chevy guys..

 

I will stand by saying that if the current 318 is anything like the old one, its a winner of a motor. The old 318 with a TF 904 was the smoothest little powerplants I've driven EVER.

 

Regards,

 

Lone

[Okimoto]

Other than than that' date=' pretty much everything else interchanges....[/quote']

 

I understand that the pre-magnum heads are slightly different than the LA heads of yore, in such a way as to require a different intake manifold.

 

However, I've been looking at the magnum engines on ebay and noticed that the exhausts look slightly different. (like the places where the studs go: top instead of bottom, bottom instead of top, etc)

 

Also, I've been reading that the new magnums block mounting locations are identical to the LA series, so one could yank a 318 out of their z, and throw in a magnum 5.9 without any driveshaft modifications and bolting up to a 727? But I'm not too positive on this one as of yet.

 

Would such a swap require a new drivers side mount?

 

I've tried reading allpar, posted on a third forum (classicrv) and I've been using the search function on this forum yielding this thread (and what I've learned from it) as a result. After reading and searching for 2 days, I am asking these questions now.

 

Also these threads with relevant information popped up:

http://forums.hybridz.org/showthread.php?t=79073

http://forums.hybridz.org/showthread.php?t=104100&page=2

 

To be honest... if I don't get an answer, I won't feel too bad since the mopar I'm referring to isn't in a Z car, it's in my motorhome. But I can't move my z out of the garage without moving the motorhome if it counts for anything! Thanks for your help.

[jbk240z]

Altough I am not a mopar guy myself, I know that the 318 makes a great boat anchor! Just kidding. If I were you I would definitely pick up the motor.

It even has fairly low miles. If I were you, I would add 4bbl intake, 650 Holley, a CompCams XE268 or XE 274 cam, headers, and put all of this into the spare Z you have in storage. A nice 4 speed manual, or even a nice A904 trans with a 2500 or so stall speed would make a very nice mild street car. Go pick up that motor, if I knew where it was, I would get it.

Good luck on your project.

[Magnum380Z]

The Magnum has plenty of power with room for more with its"quench" style heads and roller cam its an excellent engine for a conversion.as good as a Shivvy or better.

 

PS my 93 Fullsize SWB pickup ran 14.94 in the quarter with headers, exhaust, mopar perfomance computer,,modified throttle body, on stock tires and 178k on the engine.and it still managed 18mpg on the highway.

[Magnum380Z]

If you are worried about the intake MP,Mancini and a few others make a manifold with both patterns if you wanted use the FI (Iwould) you can get intouch with Street%performance they are in Mena,Arkansas they make a wiring harness to retro fit into older vehicles

[Magnum380Z]

I understand that the pre-magnum heads are slightly different than the LA heads of yore' date=' in such a way as to require a different intake manifold.

 

However, I've been looking at the magnum engines on ebay and noticed that the exhausts look slightly different. (like the places where the studs go: top instead of bottom, bottom instead of top, etc)

 

Also, I've been reading that the new magnums block mounting locations are identical to the LA series, so one could yank a 318 out of their z, and throw in a magnum 5.9 without any driveshaft modifications and bolting up to a 727? But I'm not too positive on this one as of yet.

 

Would such a swap require a new drivers side mount?

 

I've tried reading allpar, posted on a third forum (classicrv) and I've been using the search function on this forum yielding this thread (and what I've learned from it) as a result. After reading and searching for 2 days, I am asking these questions now.

 

Also these threads with relevant information popped up:

http://forums.hybridz.org/showthread.php?t=79073

http://forums.hybridz.org/showthread.php?t=104100&page=2

 

To be honest... if I don't get an answer, I won't feel too bad since the mopar I'm referring to isn't in a Z car, it's in my motorhome. But I can't move my z out of the garage without moving the motorhome if it counts for anything! Thanks for your help.[/quote']

 

the Magnum series engines are balanced differently from the Pre-magnums so you are going to have to get the correct balancer as well as flywheel/ or converter weights