5.9L Magnum questions

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Hot rodding is fun, ain't it. :D

I went with Ken's 1280 grind on RRR's recommendation. But I'm running Edelbrock 2.02 heads so the .517 lift wasn't a concern. I love it.

I sent my short block out for hot tank, hone, polish crank, new rings, main, rod, and cam bearings. Then I put it together myself.

Supposed to have had 75,000 miles on it. Plenty of cross hatch, but cam bearings were all toast (pretty normal).

Happy Hot Rodding!
 
Got to the point where I wanted to inspect all the bearings. Here's what I found out when I was checking the first rod bearing and I pushed the piston out- a fair chunk of piston between the ring grooves was just held in by the rings and bore. Fell out into my hand. Rod bearings are pretty worn, but no scratches. Cam bearing is DONE, pieces stuck to the pickup screen. Looks like it was eaten by acid. Yippee.

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MechNerd said:
Got to the point where I wanted to inspect all the bearings. Here's what I found out when I was checking the first rod bearing and I pushed the piston out- a fair chunk of piston between the ring grooves was just held in by the rings and bore. Fell out into my hand. Rod bearings are pretty worn, but no scratches. Cam bearing is DONE, pieces stuck to the pickup screen. Looks like it was eaten by acid. Yippee.

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That is why you always check, gaskets are cheap.
 
Looks like typical Magnum stuff. Sealed Power replacement pistons/pins are 176 and change from Summit Racing.
 
I obviously need new cam bearings. Do I have to buy a tool for this job, or is there a decent way to get them out/in without one?
 
MechNerd said:
I obviously need new cam bearings. Do I have to buy a tool for this job, or is there a decent way to get them out/in without one?
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Yes, requires the tool. If you're careful, you don't need the tool for removal. You'll have to be very careful not to nick or gouge the bores taking them out. So, if you're taking it to a shop for a hone and clean up, just have them do the cam bearings too.
 
408 swinger said:
if you're taking it to a shop for a hone and clean up, just have them do the cam bearings
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That's what I did when I swapped to a Magnum.

I tore it down to just crank, pistons, and rods. Had them tear it down and hot tank it, polish the crank, new main, rod and came bearings, hone and new rings. I took it from there and finished the build with a reground cam from Oregon Cam Grinding, Edelbrock 2.02 heads, air gap and carb.

At first I ran an electric fuel pump but later bought the Hughes Cam extension and switched back to a mechanical pump.
 
408 swinger said:
Yes, requires the tool. If you're careful, you don't need the tool for removal. You'll have to be very careful not to nick or gouge the bores taking them out. So, if you're taking it to a shop for a hone and clean up, just have them do the cam bearings too.
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^^^ this right here.

if you're rolling to the machine shop to have other work done anyway, have them bust out the cam bearings drop the cam in do the freeze plugs/galley plugs etx.

it'll probably be cheaper than tool and two sets of cam bearings (you'll gack at least one getting them in, so you'll buy two sets).
 
66fyssh said:
That's what I did when I swapped to a Magnum.

I tore it down to just crank, pistons, and rods. Had them tear it down and hot tank it, polish the crank, new main, rod and came bearings, hone and new rings. I took it from there and finished the build with a reground cam from Oregon Cam Grinding, Edelbrock 2.02 heads, air gap and carb.

At first I ran an electric fuel pump but later bought the Hughes Cam extension and switched back to a mechanical pump.
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Sounds like what I was planning ( except with iron heads). What grind did you go with from Oregon? How does it run?
 
On @RustyRatRod advice I went with the #1280 grind. It's .215 / .223 @ .050 and .517 with 1.6 roller rockers.

I'm running a PTC 9.5" converter and 3:23 gears, but 3:55's are coming before long.

Runs great! I have no complaints. I planned to take it to a local track in Georgia, but didn't get the chance before moving to Florida. Now the closet track is a long drive. I'm not a racer, but I'd love to know what it could run!
 
dogbreath said:
They used to be cheap but not anymore .
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Like $60 for a full set, yes I am old enough to remember an entire gasket set was $30 for a sbm, but what did you pay for the engine, if you just sent that one you would be buying another.
So cheaper on the pocketbook in the long run.
 
junkyardhero said:
^^^ this right here.

if you're rolling to the machine shop to have other work done anyway, have them bust out the cam bearings drop the cam in do the freeze plugs/galley plugs etx.

it'll probably be cheaper than tool and two sets of cam bearings (you'll gack at least one getting them in, so you'll buy two sets).
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Ha! Because I know more that EVERYONE, and my installation/removal abilities are far beyond everyone else's, I bought the tool and installed the cam bearings myself.
THREE sets of bearings. Three. #4 bearing hates me.
Oh wait...ended up buying the H116CP pistons too, because if you need pistons, you should at least get the compression height/squeeze you're paying for.
Already spent too much...but the cam should be back from Oregon tomorrow, so....I still spent too much money.
 
MechNerd said:
Ha! Because I know more that EVERYONE, and my installation/removal abilities are far beyond everyone else's, I bought the tool and installed the cam bearings myself.
THREE sets of bearings. Three. #4 bearing hates me.
Oh wait...ended up buying the H116CP pistons too, because if you need pistons, you should at least get the compression height/squeeze you're paying for.
Already spent too much...but the cam should be back from Oregon tomorrow, so....I still spent too much money.
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Sounds like how I roll. Don’t tell me I can’t do it. It’s only a matter of time and money before I come out on top.
Good luck with the rest of the build.
 
MechNerd said:
Ha! Because I know more that EVERYONE, and my installation/removal abilities are far beyond everyone else's, I bought the tool and installed the cam bearings myself.
THREE sets of bearings. Three. #4 bearing hates me.
Oh wait...ended up buying the H116CP pistons too, because if you need pistons, you should at least get the compression height/squeeze you're paying for.
Already spent too much...but the cam should be back from Oregon tomorrow, so....I still spent too much money.
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*laughs*

i feel your pain, amigo. glad you got it done though! bask in your magnificence!
 
So the build has changed a little since I've gotten further into the motor -

2 stock pistons cracked, don't trust the rest. Ordered H116CP's. At my deck height they will stick above from .006 -.015.
Got my reground roller cam back from Oregon yesterday- #2204 grind, 213/220 @ .050”, 265/275 adv, .480”/.498” lift, 110 sep.
Wallace calculator says 10.3 compression with new pistons (assumes 65cc chamber). Haven't checked yet.
Started cleaning up the ports- just bowl blend and removing any ridges/machine work that impede air. Deshrouding valves mainly.
Comp 901 springs going in.
2800 stall going in the 727 behind it. Still planning 3.55 gear, and the biggest tires I can wedge under that little car.
Chinese intake w/ 650 CFM carb.

Does this sound like a reasonable combo for the street, and may actually get some gas mileage?
If not, what would you change? BTW, I already spent more than I planned, but that's part of the game...
 
Are the pistons standard bore?
Do you plan to have the rotating assembly balanced?
If it were me I'd probably just find a couple used pistons, rering it and save the cash.
Whatever mpg gains you get from the pistons will be offset by having to run 91, 87 swill for the win :lol:
 
skep419 said:
Are the pistons standard bore?
Do you plan to have the rotating assembly balanced?
If it were me I'd probably just find a couple used pistons, rering it and save the cash.
Whatever mpg gains you get from the pistons will be offset by having to run 91, 87 swill for the win :lol:
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Yep, std. bore pistons. Wasn't planning on balancing. Even if I replaced a couple stock pistons, I'd probably be in the same boat.
 
I’d not replace the pistons if you do not plan to balance it. That’s a necessary step in my opinion even for a quicky build. And you might want to check the clearance between that h116cp and the closed portion of the magnum head if you’re above deck. Head gasket thickness will be important.
 
Stock magnum 5.9 pistons are 1.612
H116cp are 1.660
Magnum 5.9s I’ve measured stock are .051-.053 in the hole.
So that piston puts you .005-.003 down in the hole on a nominal deck height. That’s pretty good for bolt together stuff. You can use the head gasket to set quench. But as I said above, please have it balanced.
 
One more question- I was doing a little grind/polish on my iron heads, and was inspecting the typical cracks between the valve seats. Both ends of the heads on the exhaust had the crack run about 1/4" or more down into the bowl. Take a look at the pic and let me know if you think this will cause a problem. Thanks.

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I'm usually the first guy to say you can run cracked Magnum heads without any issues. 6 out of my 8 cylinders had cracks, and I'm not worried in the slightest. But your picture shows a deep and substantial crack!

Do I also see another crack going horizontally, at the bottom of the vertical crack??

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I would struggle with the idea of using that head. But I would be interested in hearing about others' experiences on this.

Given that they are almost always cracked you can normally find them pretty cheap, so you might want to check the local classifieds / Marketplace and see if you can find another pair. Out of 4 heads hopefully you would be able to find 2 you're comfortable with.

For reference, my heads had the types of cracks shown in the pic below. I didn't even see most of the cracks until I started lapping the valves:

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autopar3000 said:
I would struggle with the idea of using that head. But I would be interested in hearing about others' experiences on this.

Given that they are almost always cracked you can normally find them pretty cheap, so you might want to check the local classifieds / Marketplace and see if you can find another pair. Out of 4 heads hopefully you would be able to find 2 you're comfortable with.

For reference, my heads had the types of cracks shown in the pic below. I didn't even see most of the cracks until I started lapping the valves:

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I'd like to get others input too, but from the perspective of what they would do if the $$ was coming out of THEIR pocket.
 
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