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Magnum head combustion chambers????

MoparsOnly

The snozberries taste like snozberries.
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OK has anybody got a definitive answer for the cc of a 5.2/318 magnum head. I've seen 60cc's all the way up to 65cc's. This Is my first magnum, usually I'm building an LA. Thanks
 
Copied from Dodge Forum. If you need to know for sure you will need to measure yours and some will measure differently depending how flat the heads are and how high or low the valves are.
Combustion Chamber size...nominal 65 cc according to Hot Rod in 'Magnum
Manifesto' article in Aug 1998...62 cc according to Marlan Davis in 'High Perf
Mopar Engines' ISBN 1884089518 ....62cc as measured by Ray Barton Engines on
Dakota owner's 1995 5.2V8. Several moparts.com forum members report they have
measured Magnum chambers at 62-64cc.
 
Before going magnum again 3.9 I will simply jump to a Hemi. Magnum heads seen to develop heat cracks so I have been told.
 
No can do 7 Its a 98 ram It came with the magnum. I'm basically doing a stock rebuild. I'm just trying to find out info on this POS. I love my LA's. I wish I could just throw my 410 LA that Is ready to go. I really don't see what the big deal Is with these heads.
 
Never had a problem with the V6 magnum heads and have never owned a V8 magnum. Whatever you decide have the heads checked by a good head shop before wasting money on them.
 
Yup. My guy Is going to do all the seats and I'm replacing the valves with some nice SBI valves and a Hughes spring kit. That should be golden.
 
That is all good but without check chambers and the finished surfaces it is all a waste of time and money.
 
Gasket surface. I am not refiring to just dropping a straight edge on it either. Just because it was sealing when took off doesn't mean it will again.
 
OK went to install crank and, everything went smooth until I torqued It down and after It would not turn. I checked clearance and It's at .0020 so that's In spec. So I'm perplexed about this. It's a stock crank and hasn't been cut just polished. :banghead:
 
OK went to install crank and, everything went smooth until I torqued It down and after It would not turn. I checked clearance and It's at .0020 so that's In spec. So I'm perplexed about this. It's a stock crank and hasn't been cut just polished. :banghead:
Oops. .002 on all mains? Are all the caps in the right order and direction? Rubber or rope seal? I always start with the thrust and pry the crank for and aft to set it then torque the middle mains working out. Turn the crank by hand after each torquing. If all od a sudden one is tight, you know which one is causing the problem.
 
Oops. .002 on all mains? Are all the caps in the right order and direction? Rubber or rope seal? I always start with the thrust and pry the crank for and aft to set it then torque the middle mains working out. Turn the crank by hand after each torquing. If all od a sudden one is tight, you know which one is causing the problem.
Caps are correct and rubber seal. That's my exact process except for the turning. I will try that tomorrow.
 
Check and make sure the bearings are in the right place. Thrust is a no given. Have never had a magnum apart to no for sure if order is important on the rest. But I would pay close attention to the rear rearing.
 
I'll tell ya I'm really hating this magnum. I never had problems like this with any other LA, B, RB, builds.
 
I think I figured out the problem. I was using lucas assembly lube It's green and super tacky. I took everything apart cleaned off the lucas. I then got some Lubriplate assembly lube It's still a little tacky but not even close to what the lucas Is. I re-assembled everything and no problems well, except for a piston ring breaking. This has been the most difficult build I have ever done. It's been one thing after the next after the next...
 
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