'71 360 VS '98 360

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I'm not a magnum guy. I don't run hydraulic rollers so the block is no big deal to me. I detest stud mounted rockers. Even the Chevy guys hardly use them any more. Why would Chrysler guys think that stud mounted rockers are the best option?
 
69valiant21 said:
I already bought a 71 long block 360. But just found this 98 360 out of a jeep. This is a roller block right? Only paid $150 for the '71 and the '98 is only $220. Wouldnt be out that much. Thoughts?

1998 Jeep Grand Cherokee limited 5.9 engine 187k
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magnum heads are notorious for cracking... the 98 is gonna be a magnum 360. I'd just run what you've got. Powerwise, they are gonna be fairly close, stock for stock with the 71 LA360 coming in at 245 HP Net and the 98 Magnum rated at 230 hp net.
 
Are you doing a full rebuild or freshing up?
The stock magnum heads seem to work a bit better in stock form. My car has the 380hp create engine which is a stock magnum long block with cam, 4bbl and headers and seem to dyno 400-420hp.

Never seen a stock LA built to similar specs and dyno but I think the 1.88 valves and slightly less cr wouldn't help.

But if your plans are to port with 2.02 valves and higher CR pistons. The differences is less. LA heads seem to respond better to porting plus magnums are said to have a head cracking problem . You can buy hydraulic roller for the LA you'd save a little on the magnum if you plan on reusing the lifters.

It's a mixed bag really if you talking block only there pretty much the same except LA can use any head and magnum can use factory hydraulic roller. And if your LA is 71 it's said to have thicker bores.
 
69valiant21 said:
I already bought a 71 long block 360. But just found this 98 360 out of a jeep. This is a roller block right? Only paid $150 for the '71 and the '98 is only $220. Wouldnt be out that much. Thoughts?

1998 Jeep Grand Cherokee limited 5.9 engine 187k
Click to expand...

I like the LA style engines over the magnums...

I know a guy near you that can do them heads up for the 71 real nice... He lives 10 minutes from Metro Airport...
 
Can always put magnums on a LA, and Mopar probably put pedestal rockers on for cost cutting. How much does 5 special shaft hold downs and a shaft cost (x2) and the additional machining cost to bore the shaft saddles over a few million motors?
 
krazykuda said:
I like the LA style engines over the magnums...

I know a guy near you that can do them heads up for the 71 real nice... He lives 10 minutes from Metro Airport...
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I like the sound of that. I work north of the airport and live south of the airport. PM me details?
 
Magnum for me. Factory bottom end is very strong. People throw 400 horse at them all the time. Heads breath better. Eq heads even better and don't crack etc. Stud mounted rockers aren't ideal, true. And loving the hyd roller cam /lifters. Thin rings so usually very little bore wear, etc.
 
pishta said:
Can always put magnums on a LA, and Mopar probably put pedestal rockers on for cost cutting. How much does 5 special shaft hold downs and a shaft cost (x2) and the additional machining cost to bore the shaft saddles over a few million motors?
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Exactly. Chrysler didn't go to stud mounted rockers because they are better.
 
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